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Marzok M, Alkashif K, Kandeel M, Salem M, Sayed-Ahmed MZ, Selim A. Seroprevalence of Rift Valley Fever virus in one-humped camels (Camelus dromedaries) in Egypt. Trop Anim Health Prod 2023; 55:345. [PMID: 37789189 DOI: 10.1007/s11250-023-03765-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Accepted: 09/12/2023] [Indexed: 10/05/2023]
Abstract
Rift Valley fever (RVF) is a mosquito-borne viral disease that affects a variety of domestic animals, including cattle, sheep, goats, and camels, and has zoonotic potential. Although the rift valley fever virus (RVFV) is usually asymptomatic in camels, it can induce abortion in some pregnant animals. In the current study, a serosurvey was carried out to investigate the prevalence of RVFV antibodies and related risk factors in camels from four Egyptian governorates. A total of 400 serum samples were examined for anti-RVFV antibodies using a competitive enzyme-linked immunosorbent assay (c-ELISA). The results revealed that the overall prevalence of RVF among examined camels was 21.5% and the disease was more prevalent in Kafr ElSheikh governorate in Nile Delta of Egypt. In addition, the age group of camels with more than 5 years (OR=4.49, 95%CI: 1.39-14.49), the female sex (OR=3.38, 95%CI: 1.51-7.58), the emaciated animals (OR=1.52, 95%CI: 0.86-2.66), the summer season's infection (OR=5.98, 95%CI: 1.79-19.93), the presence of mosquitoes (OR= 2.88, 95%CI: 1.39-5.95), and the absence of mosquitoes control (OR=3.97, 95%CI: 2.09-7.57) were identified as risk factors for RVFV infection. The results of this study support knowledge on the risk factors for RVFV infection and demonstrate that camels raising in Egypt have RVFV antibodies. Quarantine measures or vaccination program should be implemented to reduce the likelihood of RVFV introduction, dissemination among susceptible animals, and ultimately transmission to humans.
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Affiliation(s)
- Mohamed Marzok
- Department of Clinical Sciences, College of Veterinary Medicine, King Faisal University, Al-Ahsa, 31982, Saudi Arabia.
- Department of Surgery, Faculty of Veterinary Medicine, Kafr El Sheikh University, Kafr El Sheikh, Egypt.
| | - Khalid Alkashif
- Department of Pharmacology and Toxicology, College of Pharmacy, Jazan University, Jazan, 82722, Saudi Arabia
| | - Mahmoud Kandeel
- Department of Pharmacology, Faculty of Veterinary Medicine, Kafr elsheikh University, Kafrelsheikh, Egypt
- Department of Biomedical Sciences, College of Veterinary Medicine, King Faisal University, Al-Ahsa, Saudi Arabia
| | - Mohamed Salem
- Department of Clinical Pharmacy, College of Pharmacy, Jazan University, Jazan, 45142, Saudi Arabia
- Department of Medicine and Infectious Diseases, Faculty of Veterinary Medicine, Cairo University, Cairo, 12613, Egypt
| | - Mohamed Z Sayed-Ahmed
- Department of Internal Medicine and Infectious Diseases, Faculty of Veterinary Medicine, Mansoura University, Mansoura, 35516, Egypt
- Department of Animal Medicine (Infectious Diseases), Faculty of Veterinary Medicine, Benha University, Toukh, 13736, Egypt
| | - Abdelfattah Selim
- Department of Animal Medicine (Infectious Diseases), Faculty of Veterinary Medicine, Benha University, Toukh, 13736, Egypt.
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Ebogo‐Belobo JT, Kenmoe S, Abanda NN, Bowo‐Ngandji A, Mbaga DS, Magoudjou‐Pekam JN, Kame‐Ngasse GI, Tchatchouang S, Menkem EZ, Okobalemba EA, Noura EA, Meta‐Djomsi D, Maïdadi‐Foudi M, Kenfack‐Zanguim J, Kenfack‐Momo R, Kengne‐Nde C, Esemu SN, Mbacham WF, Sadeuh‐Mba SA, Ndip L, Njouom R. Contemporary epidemiological data of Rift Valley fever virus in humans, mosquitoes and other animal species in Africa: A systematic review and meta-analysis. Vet Med Sci 2023; 9:2309-2328. [PMID: 37548116 PMCID: PMC10508527 DOI: 10.1002/vms3.1238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Revised: 03/29/2023] [Accepted: 07/21/2023] [Indexed: 08/08/2023] Open
Abstract
Rift Valley fever (RVF) is a severe zoonotic mosquito-borne disease that represents an important threat to human and animal health, with major public health and socioeconomic impacts. This disease is endemic throughout many African countries and the Arabian Peninsula. This systematic review with meta-analysis was conducted to determine the RVF prevalence in humans, mosquitoes and other animal species in Africa. The review also provides contemporary data on RVF case fatality rate (CFR) in humans. In this systematic review with meta-analysis, a comprehensive literature search was conducted on the PubMed, Embase, Web of Science and Global Index Medicus databases from January 2000 to June 2022 to identify relevant studies. Pooled CFR and prevalence estimates were calculated using the random-effects model. Subgroup analysis and sensitivity analysis were performed, and the I2 -statistic was used to investigate a potential source of heterogeneity. A total of 205 articles were included in the final analysis. The overall RVF CFR in humans was found to be 27.5% [95% CI = 8.0-52.5]. The overall pooled prevalence was 7.8% [95% CI = 6.2-9.6] in humans and 9.3% [95% CI = 8.1-10.6] in animals, respectively. The RVF prevalence in individual mosquitoes ranged from 0.0% to 25%. Subgroup analysis showed substantial heterogeneity with respect to geographical regions and human categories. The study shows that there is a correspondingly similar prevalence of RVF in human and animals; however, human CFR is much higher than the observed prevalence. The lack of a surveillance programme and the fact that this virus has subclinical circulation in animals and humans could explain these observations. The implementation of a One Health approach for RVF surveillance and control would be of great interest for human and animal health.
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Affiliation(s)
- Jean Thierry Ebogo‐Belobo
- Centre for Research on Health and Priority PathologiesInstitute of Medical Research and Medicinal Plants StudiesYaoundeCameroon
- Department of BiochemistryFaculty of SciencesThe University of Yaounde IYaoundéCameroon
| | - Sebastien Kenmoe
- Department of Microbiology and ParasitologyUniversity of BueaBueaCameroon
| | - Ngu Njei Abanda
- Virology DepartmentCentre Pasteur of CameroonYaoundéCameroon
| | - Arnol Bowo‐Ngandji
- Department of MicrobiologyFaculty of SciencesThe University of Yaounde IYaoundéCameroon
| | - Donatien Serge Mbaga
- Department of MicrobiologyFaculty of SciencesThe University of Yaounde IYaoundéCameroon
| | | | - Ginette Irma Kame‐Ngasse
- Centre for Research on Health and Priority PathologiesInstitute of Medical Research and Medicinal Plants StudiesYaoundeCameroon
| | | | | | | | - Efietngab Atembeh Noura
- Centre for Research on Health and Priority PathologiesInstitute of Medical Research and Medicinal Plants StudiesYaoundeCameroon
| | - Dowbiss Meta‐Djomsi
- Research Centre on Emerging and Re‐Emerging DiseasesInstitute of Medical Research and Medicinal Plants StudiesYaoundeCameroon
| | - Martin Maïdadi‐Foudi
- Research Centre on Emerging and Re‐Emerging DiseasesInstitute of Medical Research and Medicinal Plants StudiesYaoundeCameroon
| | | | - Raoul Kenfack‐Momo
- Department of BiochemistryFaculty of SciencesThe University of Yaounde IYaoundéCameroon
| | - Cyprien Kengne‐Nde
- Epidemiological Surveillance, Evaluation and Research UnitNational AIDS Control CommitteeYaoundéCameroon
| | | | - Wilfred Fon Mbacham
- Department of BiochemistryFaculty of SciencesThe University of Yaounde IYaoundéCameroon
| | - Serge Alain Sadeuh‐Mba
- Virology DepartmentCentre Pasteur of CameroonYaoundéCameroon
- Maryland Department of AgricultureSalisbury Animal Health LaboratorySalisburyMarylandUSA
| | - Lucy Ndip
- Department of Microbiology and ParasitologyUniversity of BueaBueaCameroon
| | - Richard Njouom
- Virology DepartmentCentre Pasteur of CameroonYaoundéCameroon
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Tercero B, Terasaki K, Narayanan K, Makino S. Mechanistic insight into the efficient packaging of antigenomic S RNA into Rift Valley fever virus particles. Front Cell Infect Microbiol 2023; 13:1132757. [PMID: 36875526 PMCID: PMC9978001 DOI: 10.3389/fcimb.2023.1132757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Accepted: 02/06/2023] [Indexed: 02/18/2023] Open
Abstract
Rift Valley fever virus (RVFV), a bunyavirus, has a single-stranded, negative-sense tri-segmented RNA genome, consisting of L, M and S RNAs. An infectious virion carries two envelope glycoproteins, Gn and Gc, along with ribonucleoprotein complexes composed of encapsidated viral RNA segments. The antigenomic S RNA, which serves as the template of the mRNA encoding a nonstructural protein, NSs, an interferon antagonist, is also efficiently packaged into RVFV particles. An interaction between Gn and viral ribonucleoprotein complexes, including the direct binding of Gn to viral RNAs, drives viral RNA packaging into RVFV particles. To understand the mechanism of efficient antigenomic S RNA packaging in RVFV, we identified the regions in viral RNAs that directly interact with Gn by performing UV-crosslinking and immunoprecipitation of RVFV-infected cell lysates with anti-Gn antibody followed by high-throughput sequencing analysis (CLIP-seq analysis). Our data suggested the presence of multiple Gn-binding sites in RVFV RNAs, including a prominent Gn-binding site within the 3' noncoding region of the antigenomic S RNA. We found that the efficient packaging of antigenomic S RNA was abrogated in a RVFV mutant lacking a part of this prominent Gn-binding site within the 3' noncoding region. Also, the mutant RVFV, but not the parental RVFV, triggered the early induction of interferon-β mRNA expression after infection. These data suggest that the direct binding of Gn to the RNA element within the 3' noncoding region of the antigenomic S RNA promoted the efficient packaging of antigenomic S RNA into virions. Furthermore, the efficient packaging of antigenomic S RNA into RVFV particles, driven by the RNA element, facilitated the synthesis of viral mRNA encoding NSs immediately after infection, resulting in the suppression of interferon-β mRNA expression.
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Affiliation(s)
- Breanna Tercero
- Department of Microbiology and Immunology, The University of Texas Medical Branch, Galveston, TX, United States
| | - Kaori Terasaki
- Department of Microbiology and Immunology, The University of Texas Medical Branch, Galveston, TX, United States
- Institute for Human Infections and Immunity, The University of Texas Medical Branch, Galveston, TX, United States
| | - Krishna Narayanan
- Department of Microbiology and Immunology, The University of Texas Medical Branch, Galveston, TX, United States
| | - Shinji Makino
- Department of Microbiology and Immunology, The University of Texas Medical Branch, Galveston, TX, United States
- Institute for Human Infections and Immunity, The University of Texas Medical Branch, Galveston, TX, United States
- Center for Biodefense and Emerging Infectious Diseases, The University of Texas Medical Branch, Galveston, TX, United States
- UTMB Center for Tropical Diseases, The University of Texas Medical Branch, Galveston, TX, United States
- The Sealy Institute for Vaccine Sciences, The University of Texas Medical Branch, Galveston, TX, United States
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Seroprevalence of Rift Valley fever virus in domestic ruminants of various origins in two markets of Yaoundé, Cameroon. PLoS Negl Trop Dis 2022; 16:e0010683. [PMID: 35951644 PMCID: PMC9397978 DOI: 10.1371/journal.pntd.0010683] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 08/23/2022] [Accepted: 07/20/2022] [Indexed: 01/25/2023] Open
Abstract
Background Rift Valley fever (RVF) is a mosquito-borne zoonosis endemic in Africa. With little known of the burden or epidemiology of RVF virus (RVFV) in Cameroon, this study aimed to determine the seroprevalence of RVFV in domestic ruminants of various origins in two markets of Yaoundé, Cameroon. Methodology/Principal findings The origin of animals randomly sampled at two livestock markets in Yaoundé were recorded and plasma samples collected for competitive and capture Enzyme-linked Immunosorbent Assay (ELISA) to determine the prevalence of Immunoglobulins G (IgG) and Immunoglobulins M (IgM) antibodies. Following ELISA IgM results, a real-time reverse transcription-polymerase chain reaction (qRT-PCR) was performed to detect RVFV RNA. In June-August 2019, February-March 2020, and March-April 2021, 756 plasma samples were collected from 441 cattle, 168 goats, and 147 sheep. RVFV IgG seroprevalence was 25.7% for all animals, 42.2% in cattle, 2.7% in sheep, and 2.4% in goats. However, IgM seroprevalence was low, at 0.9% in all animals, 1.1% in cattle, 1.4% in sheep, and 0% in goats. The seroprevalence rates varied according to the animal’s origin with the highest rate (52.6%) in cattle from Sudan. In Cameroon, IgG and IgM rates respectively were 45.1% and 2.8% in the North, 44.8% and 0% in the Adamawa, 38.6% and 1.7% in the Far-North. All IgM positive samples were from Cameroon. In cattle, 2/5 IgM positive samples were also IgG positive, but both IgM positive samples in sheep were IgG negative. Three (42.9%) IgM positive samples were positive for viral RVFV RNA using qRT-PCR but given the high ct values, no amplicon was obtained. Conclusion/Significance These findings confirm the circulation of RVFV in livestock in Cameroon with prevalence rates varying by location. Despite low IgM seroprevalence rates, RVF outbreaks can occur without being noticed. Further epidemiological studies are needed to have a broad understanding of RVFV transmission in Cameroon.
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Freeman AYS, Rumunu JP, Modi ZA, Guyo AG, Achier AAU, Alor NAJ, Ochan TDK, Ochan WA, Maleghemi S, Berta KK, Olu OO. Assessment of infection prevention and control readiness for Ebola virus and other diseases outbreaks in a humanitarian crisis setting: a cross-sectional study of health facilities in six high-risk States of South Sudan. Pan Afr Med J 2022; 42:10. [PMID: 36158936 PMCID: PMC9475050 DOI: 10.11604/pamj.supp.2022.42.1.33906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Accepted: 05/30/2022] [Indexed: 11/26/2022] Open
Abstract
INTRODUCTION the study was conducted to assess the readiness and capacity of the core components of infection prevention and control and water, sanitation and hygiene in health facilities to effectively contain potential outbreaks of Ebola virus and other diseases in South Sudan. METHODS it is a descriptive cross-sectional study which was conducted in health facilities in six high-risk States of the country from September 2020 to December 2021. Data was collected using a structured questionnaire and analyzed with Microsoft Excel software. RESULTS one hundred and fifty-one (151) health facilities with a total bed capacity of 3089 were enrolled into the study. Overall, the least prepared infection prevention and control, water and sanitation core components in ascending order were the coordination committee structure (13.19%), guidelines and SOPs (21.85%), vector control (22.02%), staff management (30.63%), and training received (33.64%). The best prepared components in descending order were integrated disease surveillance and response capacity (69.83%), medical waste management system (57.12%) and infrastructure compliance (54.69%). CONCLUSION the findings of this study which is comparable to those of other studies in similar settings validates the perception that Infection Prevention and Control/Water, Sanitation, and Hygiene (IPC/WASH) capacity and readiness is inadequate in South Sudan. To scale up these core components, we recommend development and implementation of a comprehensive and long-term infection prevention and control strategic plan as part of the country's broader health sector recovery planning.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Olushayo Oluseun Olu
- World Health Organization, Juba, South Sudan,,Corresponding author Olushayo Oluseun Olu, World Health Organization, Juba, South Sudan.
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Ramadan OPC, Berta KK, Wamala JF, Maleghemi S, Rumunu J, Ryan C, Ladu AI, Joseph JLK, Abenego AA, Ndenzako F, Olu OO. Analysis of the 2017-2018 Rift valley fever outbreak in Yirol East County, South Sudan: a one health perspective. Pan Afr Med J 2022; 42:5. [PMID: 36158935 PMCID: PMC9474954 DOI: 10.11604/pamj.supp.2022.42.1.33769] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Accepted: 05/30/2022] [Indexed: 12/02/2022] Open
Abstract
INTRODUCTION the emergence and re-emergence of zoonotic diseases have threatened both human and animal health globally since their identification in the 20th century. Rift Valley fever (RVF) virus is a recurrent zoonotic disease in South Sudan, with the earliest RVF cases confirmed in 2007 in Kapoeta North County, Eastern Equatoria state. METHODS we analyzed national RVF outbreak data to describe the epidemiological pattern of the RVF outbreak in Yirol East county in Lakes State. The line list of cases (confirmed, probable, suspected, and non-cases) was used to describe the pattern and risk factors associated with the outbreak. The animal and human blood samples were tested using Enzyme-Linked Immunosorbent Assay (ELISA) (Immunoglobulin IgG and IgM) and Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR). Qualitative data were collected from weekly RVF situation reports, and national guidelines and policies. RESULTS between December 2017 and December 2018, 58 suspected human RVF cases were reported. The cases were reclassified based on laboratory and investigations results, such that as of 16th December 2018, there were a total of six (10.3%) laboratory-confirmed, three (5.2%) probable, one (1.7%) suspected, and 48 (82.8%) non-cases were reported. A total of four deaths were reported during the outbreak (case fatality rate (CFR) 6.8% (4/58). A total of 28 samples were collected from animals; of these, six tested positives for RVF (positivity rate of 32.1% (9/28). The outbreak was announced in March 2018, after four months of the first reported suspected RVF case. Several factors were attributed to the delayed notification and outbreak announcement such as lack of multi-sectorial coordination at the state and county level, multi-sectoral coordination at national level mostly attended by public health experts from human health, inadequate animal health surveillance, poor coordination between livestock disease surveillance and public health surveillance, limited in-country laboratory diagnostic capacity, the laboratory results for the animal health took longer than expected, and lack of a national One Health approach strategy. CONCLUSION the outbreak demonstrated gaps to investigate and respond to zoonotic disease outbreaks in South Sudan.
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Affiliation(s)
- Otim Patrick Cossy Ramadan
- World Health Organization, East and South Africa, Sub Regional Office, Nairobi, Kenya,,Corresponding author Kibebu Kinfu, World Health Organization, Country Office, Juba, South Sudan.
| | | | | | | | - John Rumunu
- Ministry of Health, Juba, Republic of South Sudan
| | - Caroline Ryan
- World Health Organization, East and South Africa, Sub Regional Office, Nairobi, Kenya
| | - Alice Igale Ladu
- World Health Organization (WHO), WHO Country Office, Juba, South Sudan
| | | | | | - Fabian Ndenzako
- World Health Organization (WHO), WHO Country Office, Juba, South Sudan
| | - Olushayo Oluseun Olu
- World Health Organization, East and South Africa, Sub Regional Office, Nairobi, Kenya
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Rumunu J, Wamala JF, Sakaya R, Konga SB, Igale AL, Adut AA, Lonyik SK, Lasu RM, Kaya RD, Guracha G, Nsubuga P, Ndenzako F, Talisuna AO. Evaluation of integrated disease surveillance and response (IDSR) and early warning and response network (EWARN) in South Sudan 2021. Pan Afr Med J 2022; 42:6. [PMID: 36158929 PMCID: PMC9474832 DOI: 10.11604/pamj.supp.2022.42.1.33780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Accepted: 03/05/2022] [Indexed: 11/11/2022] Open
Abstract
Introduction South Sudan has been implementing the Integrated Disease Surveillance and Response (IDSR) strategy since 2006, along with Early Warning and Alert Response and Network (EWARN). The IDSR/EWARN stakeholders commissioned an independent evaluation to establish performance at national, state, county, health facility, and community levels in the first half of 2021. Methods the evaluation was conducted between June and September 2021 (during the COVID-19 pandemic) and was based on the World Health Organization (WHO) protocols for monitoring and evaluating communicable disease surveillance and response systems and the guidelines for evaluating EWARN. Results integrated disease surveillance and response/early warning and alert response and network indicator data showed improving timeliness and completeness from the beginning of 2021 to week 16 and then a slight depression of timeliness by week 32, while completeness remained high. Event-based surveillance was active at the beginning of 2021 and in week 32. However, there was inadequate sample collection to investigate acute watery diarrhea, bloody diarrhea, and acute jaundice syndrome alerts. Respondents in all cadres had substantial experience working in IDSR/EWARN. All respondents performed the various IDSR/EWARN tasks and duties as expected, but needed more resources and training. Conclusion while IDSR/EWARN is performing relatively well, confirmation of priority diseases by the laboratories needs to be strengthened. Health facilities need more regular supervision from the higher levels. Community health workers need more training on IDSR/EWARN. The whole IDSR/EWARN system needs more resources, particularly for communication and transport and to confirm priority diseases. Staff at all levels requested more training in IDSR/EWARN.
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Affiliation(s)
- John Rumunu
- Doctoral Program in Global Health, Humanitarian Aid and Disaster Medicine, Universita Del Pemonte Orientale and Vrije University Brussel, Juba, South Sudan,Corresponding author John Rumunu, Doctoral Program in Global Health, Humanitarian Aid and Disaster Medicine, Universita Del Pemonte Orientale and Vrije University Brussel, Juba, South Sudan.
| | | | | | - Sheila Baya Konga
- World Health Organization Country Office for South Sudan, Juba, South Sudan
| | - Alice Lado Igale
- World Health Organization Country Office for South Sudan, Juba, South Sudan
| | | | | | - Robert Martin Lasu
- World Health Organization Country Office for South Sudan, Juba, South Sudan
| | - Rose Dagama Kaya
- World Health Organization Country Office for South Sudan, Juba, South Sudan
| | - Guyo Guracha
- World Health Organization Country Office for South Sudan, Juba, South Sudan
| | | | - Fabian Ndenzako
- World Health Organization Country Office for South Sudan, Juba, South Sudan
| | - Ambrose Otau Talisuna
- World Health Organization Regional Office for Africa, Brazzaville, Republic of Congo
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Rugarabamu S, Mwanyika GO, Rumisha SF, Sindato C, Lim HY, Misinzo G, Mboera LEG. Seroprevalence and associated risk factors of selected zoonotic viral hemorrhagic fevers in Tanzania. Int J Infect Dis 2021; 109:174-181. [PMID: 34242761 DOI: 10.1016/j.ijid.2021.07.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 07/01/2021] [Accepted: 07/03/2021] [Indexed: 11/16/2022] Open
Abstract
OBJECTIVE To determine the seroprevalence of selected zoonotic viral hemorrhagic fevers (VHFs) and their associated risk factors in Tanzania. METHODS Blood samples were collected from consenting outpatients and community members in eight districts selected from five ecological zones of Tanzania. Serum was harvested and tested for the presence of immunoglobulin G (IgG) and M (IgM) antibodies against Crimean-Congo hemorrhagic fever (CCHF), Ebola virus disease (EVD), Marburg virus disease (MVD), Rift Valley fever (RVF), and yellow fever (YF). RESULTS The presence of IgM and IgG antibodies against CCHF, EVD, MVD, RVF, and YF was detected in 64 of 500 samples (12.8%). The prevalences of IgM and IgG antibodies to CCHF, EVD, MVD, RFV, and YF were 2.0%, 3.4%, 1.2%, 4.8%, and 1.4%, respectively. Contact with wild animals (OR = 1.2, CI = 1.3-1.6) and keeping goats (OR = 1.3, CI = 1.5-1.9) were significantly associated with RVF, while contact with bats (OR = 1.2, CI = 1.1-1.5) was associated with MVD. CONCLUSION The findings of this study provide evidence of exposure to CCHF, EVD, MVD, RVF, and YF in Tanzania. Since most of these VHFs occurred without apparent clinical forms of the disease, these findings call for the need to strengthen the surveillance system and management of febrile illnesses in Tanzania.
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Affiliation(s)
- Sima Rugarabamu
- SACIDS Foundation for One Health, Sokoine University of Agriculture, Morogoro, Tanzania; Department of Veterinary Microbiology, Parasitology and Biotechnology, Sokoine University of Agriculture, Morogoro, Tanzania; Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania.
| | - Gaspary O Mwanyika
- SACIDS Foundation for One Health, Sokoine University of Agriculture, Morogoro, Tanzania; Department of Veterinary Microbiology, Parasitology and Biotechnology, Sokoine University of Agriculture, Morogoro, Tanzania; Mbeya University of Science and Technology, Mbeya, Tanzania.
| | - Susan F Rumisha
- National Institute for Medical Research, Headquarters, Dar es Salaam, Tanzania; Malaria Atlas Project, Geospatial Health and Development, Telethon Kids Institute, Perth, Western Australia.
| | - Calvin Sindato
- SACIDS Foundation for One Health, Sokoine University of Agriculture, Morogoro, Tanzania; National Institute for Medical Research, Tabora Research Centre, Tabora, Tanzania.
| | - Hee-Young Lim
- Korea Disease Control and Prevention Agency, National Institute of Health, Osong, Chungchungbukdo, Republic of Korea.
| | - Gerald Misinzo
- SACIDS Foundation for One Health, Sokoine University of Agriculture, Morogoro, Tanzania; Department of Veterinary Microbiology, Parasitology and Biotechnology, Sokoine University of Agriculture, Morogoro, Tanzania.
| | - Leonard E G Mboera
- SACIDS Foundation for One Health, Sokoine University of Agriculture, Morogoro, Tanzania.
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Ahmed A, Ali Y, Elduma A, Eldigail MH, Mhmoud RA, Mohamed NS, Ksiazek TG, Dietrich I, Weaver SC. Unique Outbreak of Rift Valley Fever in Sudan, 2019. Emerg Infect Dis 2021; 26:3030-3033. [PMID: 33219787 PMCID: PMC7706939 DOI: 10.3201/eid2612.201599] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
We report a unique outbreak of Rift Valley fever in the Eldamar area, Sudan, May–July 2019, that resulted in 1,129 case-patients and 19 (1.7%) deaths. Patients exhibited clinical signs including fever (100%), headache (79%), and bleeding (4%). Most (98%) patients also reported death and abortions among their livestock.
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Odendaal L, Davis AS, Venter EH. Insights into the Pathogenesis of Viral Haemorrhagic Fever Based on Virus Tropism and Tissue Lesions of Natural Rift Valley Fever. Viruses 2021; 13:v13040709. [PMID: 33923863 PMCID: PMC8073615 DOI: 10.3390/v13040709] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Revised: 03/26/2021] [Accepted: 04/02/2021] [Indexed: 12/20/2022] Open
Abstract
Rift Valley fever phlebovirus (RVFV) infects humans and a wide range of ungulates and historically has caused devastating epidemics in Africa and the Arabian Peninsula. Lesions of naturally infected cases of Rift Valley fever (RVF) have only been described in detail in sheep with a few reports concerning cattle and humans. The most frequently observed lesion in both ruminants and humans is randomly distributed necrosis, particularly in the liver. Lesions supportive of vascular endothelial injury are also present and include mild hydropericardium, hydrothorax and ascites; marked pulmonary congestion and oedema; lymph node congestion and oedema; and haemorrhages in many tissues. Although a complete understanding of RVF pathogenesis is still lacking, antigen-presenting cells in the skin are likely the early targets of the virus. Following suppression of type I IFN production and necrosis of dermal cells, RVFV spreads systemically, resulting in infection and necrosis of other cells in a variety of organs. Failure of both the innate and adaptive immune responses to control infection is exacerbated by apoptosis of lymphocytes. An excessive pro-inflammatory cytokine and chemokine response leads to microcirculatory dysfunction. Additionally, impairment of the coagulation system results in widespread haemorrhages. Fatal outcomes result from multiorgan failure, oedema in many organs (including the lungs and brain), hypotension, and circulatory shock. Here, we summarize current understanding of RVF cellular tropism as informed by lesions caused by natural infections. We specifically examine how extant knowledge informs current understanding regarding pathogenesis of the haemorrhagic fever form of RVF, identifying opportunities for future research.
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Affiliation(s)
- Lieza Odendaal
- Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, Pretoria 0002, South Africa
- Correspondence: (L.O.); (A.S.D.)
| | - A Sally Davis
- Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, Pretoria 0002, South Africa
- Department of Diagnostic Medicine/Pathobiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA
- Correspondence: (L.O.); (A.S.D.)
| | - Estelle H Venter
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Pretoria 0002, South Africa;
- College of Public Health Medical and Veterinary Sciences, Discipline Veterinary Science, James Cook University, Townsville, QLD 4811, Australia
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11
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Cosseddu GM, Magwedere K, Molini U, Pinoni C, Khaiseb S, Scacchia M, Marcacci M, Capobianco Dondona A, Valleriani F, Polci A, Monaco F. Genetic Diversity of Rift Valley Fever Strains Circulating in Namibia in 2010 and 2011. Viruses 2020; 12:v12121453. [PMID: 33339456 PMCID: PMC7765780 DOI: 10.3390/v12121453] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 12/10/2020] [Accepted: 12/15/2020] [Indexed: 11/30/2022] Open
Abstract
Outbreaks of Rift Valley fever (RVF) occurred in Namibia in 2010 and 2011. Complete genome characterization was obtained from virus isolates collected during disease outbreaks in southern Namibia in 2010 and from wildlife in Etosha National Park in 2011, close to the area where RVF outbreaks occurred in domestic livestock. The virus strains were sequenced using Sanger sequencing (Namibia_2010) or next generation sequencing (Namibia_2011). A sequence-independent, single-primer amplification (SISPA) protocol was used in combination with the Illumina Next 500 sequencer. Phylogenetic analysis of the sequences of the small (S), medium (M), and large (L) genome segments of RVF virus (RVFV) provided evidence that two distinct RVFV strains circulated in the country. The strain collected in Namibia in 2010 is genetically similar to RVFV strains circulating in South Africa in 2009 and 2010, confirming that the outbreaks reported in the southern part of Namibia in 2010 were caused by possible dissemination of the infection from South Africa. Isolates collected in 2011 were close to RVFV isolates from 2010 collected in humans in Sudan and which belong to the large lineage containing RVFV strains that caused an outbreak in 2006–2008 in eastern Africa. This investigation showed that the RVFV strains circulating in Namibia in 2010 and 2011 were from two different introductions and that RVFV has the ability to move across regions. This supports the need for risk-based surveillance and monitoring.
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Affiliation(s)
- Gian Mario Cosseddu
- Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise “G. Caporale”—IZSAM, Campo Boario, 64100 Teramo, Italy; (C.P.); (M.S.); (M.M.); (A.C.D.); (F.V.); (A.P.); (F.M.)
- Correspondence: ; Tel.: +39-0861-332280
| | - Kudakwashe Magwedere
- Central Veterinary Laboratory (CVL), 13187 Windhoek, Namibia; (K.M.); (U.M.); (S.K.)
| | - Umberto Molini
- Central Veterinary Laboratory (CVL), 13187 Windhoek, Namibia; (K.M.); (U.M.); (S.K.)
| | - Chiara Pinoni
- Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise “G. Caporale”—IZSAM, Campo Boario, 64100 Teramo, Italy; (C.P.); (M.S.); (M.M.); (A.C.D.); (F.V.); (A.P.); (F.M.)
| | - Sigfried Khaiseb
- Central Veterinary Laboratory (CVL), 13187 Windhoek, Namibia; (K.M.); (U.M.); (S.K.)
| | - Massimo Scacchia
- Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise “G. Caporale”—IZSAM, Campo Boario, 64100 Teramo, Italy; (C.P.); (M.S.); (M.M.); (A.C.D.); (F.V.); (A.P.); (F.M.)
| | - Maurilia Marcacci
- Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise “G. Caporale”—IZSAM, Campo Boario, 64100 Teramo, Italy; (C.P.); (M.S.); (M.M.); (A.C.D.); (F.V.); (A.P.); (F.M.)
| | - Andrea Capobianco Dondona
- Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise “G. Caporale”—IZSAM, Campo Boario, 64100 Teramo, Italy; (C.P.); (M.S.); (M.M.); (A.C.D.); (F.V.); (A.P.); (F.M.)
| | - Fabrizia Valleriani
- Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise “G. Caporale”—IZSAM, Campo Boario, 64100 Teramo, Italy; (C.P.); (M.S.); (M.M.); (A.C.D.); (F.V.); (A.P.); (F.M.)
| | - Andrea Polci
- Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise “G. Caporale”—IZSAM, Campo Boario, 64100 Teramo, Italy; (C.P.); (M.S.); (M.M.); (A.C.D.); (F.V.); (A.P.); (F.M.)
| | - Federica Monaco
- Istituto Zooprofilattico Sperimentale dell’Abruzzo e del Molise “G. Caporale”—IZSAM, Campo Boario, 64100 Teramo, Italy; (C.P.); (M.S.); (M.M.); (A.C.D.); (F.V.); (A.P.); (F.M.)
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12
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Surtees R, Stern D, Ahrens K, Kromarek N, Lander A, Kreher P, Weiss S, Hewson R, Punch EK, Barr JN, Witkowski PT, Couacy-Hymann E, Marzi A, Dorner BG, Kurth A. Development of a multiplex microsphere immunoassay for the detection of antibodies against highly pathogenic viruses in human and animal serum samples. PLoS Negl Trop Dis 2020; 14:e0008699. [PMID: 33095766 PMCID: PMC7641473 DOI: 10.1371/journal.pntd.0008699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 11/04/2020] [Accepted: 08/11/2020] [Indexed: 11/18/2022] Open
Abstract
Surveillance of highly pathogenic viruses circulating in both human and animal populations is crucial to unveil endemic infections and potential zoonotic reservoirs. Monitoring the burden of disease by serological assay could be used as an early warning system for imminent outbreaks as an increased seroprevalance often precedes larger outbreaks. However, the multitude of highly pathogenic viruses necessitates the need to identify specific antibodies against several targets from both humans as well as from potential reservoir animals such as bats. In order to address this, we have developed a broadly reactive multiplex microsphere immunoassay (MMIA) for the detection of antibodies against several highly pathogenic viruses from both humans and animals. To this aim, nucleoproteins (NP) of Ebola virus (EBOV), Marburg virus (MARV) and nucleocapsid proteins (NP) of Crimean-Congo haemorrhagic fever virus, Rift Valley fever virus and Dobrava-Belgrade hantavirus were employed in a 5-plex assay for IgG detection. After optimisation, specific binding to each respective NP was shown by testing sera from humans and non-human primates with known infection status. The usefulness of our assay for serosurveillance was shown by determining the immune response against the NP antigens in a panel of 129 human serum samples collected in Guinea between 2011 and 2012 in comparison to a panel of 88 sera from the German blood bank. We found good agreement between our MMIA and commercial or in-house reference methods by ELISA or IIFT with statistically significant higher binding to both EBOV NP and MARV NP coupled microspheres in the Guinea panel. Finally, the MMIA was successfully adapted to detect antibodies from bats that had been inoculated with EBOV- and MARV- virus-like particles, highlighting the versatility of this technique and potentially enabling the monitoring of wildlife as well as human populations with this assay. We were thus able to develop and validate a sensitive and broadly reactive high-throughput serological assay which could be used as a screening tool to detect antibodies against several highly pathogenic viruses.
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Affiliation(s)
- Rebecca Surtees
- Biosafety Level-4 Laboratory, Centre for Biological Threats and Special Pathogens, Robert Koch Institute, Berlin, Germany
| | - Daniel Stern
- Biological Toxins, Centre for Biological Threats and Special Pathogens, Robert Koch Institute, Berlin, Germany
| | - Katharina Ahrens
- Biosafety Level-4 Laboratory, Centre for Biological Threats and Special Pathogens, Robert Koch Institute, Berlin, Germany
| | - Nicole Kromarek
- Biosafety Level-4 Laboratory, Centre for Biological Threats and Special Pathogens, Robert Koch Institute, Berlin, Germany
| | - Angelika Lander
- Biosafety Level-4 Laboratory, Centre for Biological Threats and Special Pathogens, Robert Koch Institute, Berlin, Germany
| | - Petra Kreher
- Biosafety Level-4 Laboratory, Centre for Biological Threats and Special Pathogens, Robert Koch Institute, Berlin, Germany
| | - Sabrina Weiss
- Institute of Virology, Charité -Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Germany
| | - Roger Hewson
- Virology and Pathogenesis Group, National Infection Service, Public Health England, Porton Down, United Kingdom
| | - Emma K Punch
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, United Kingdom
| | - John N Barr
- School of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, United Kingdom
| | - Peter T Witkowski
- Institute of Virology, Charité -Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Germany
| | | | - Andrea Marzi
- Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, MT, United States of America
| | - Brigitte G Dorner
- Biological Toxins, Centre for Biological Threats and Special Pathogens, Robert Koch Institute, Berlin, Germany
| | - Andreas Kurth
- Biosafety Level-4 Laboratory, Centre for Biological Threats and Special Pathogens, Robert Koch Institute, Berlin, Germany
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13
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Hoste ACR, Ruiz T, Fernández-Pacheco P, Jiménez-Clavero MÁ, Djadjovski I, Moreno S, Brun A, Edwards TA, Barr JN, Rueda P, Sastre P. Development of a multiplex assay for antibody detection in serum against pathogens affecting ruminants. Transbound Emerg Dis 2020; 68:1229-1239. [PMID: 32767820 PMCID: PMC8246919 DOI: 10.1111/tbed.13776] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 07/02/2020] [Accepted: 08/03/2020] [Indexed: 12/03/2022]
Abstract
Numerous infectious diseases impacting livestock impose an important economic burden and in some cases also represent a threat to humans and are classified as zoonoses. Some zoonotic diseases are transmitted by vectors and, due to complex environmental and socio‐economic factors, the distribution of many of these pathogens is changing, with increasing numbers being found in previously unaffected countries. Here, we developed a multiplex assay, based on a suspension microarray, able to detect specific antibodies to five important pathogens of livestock (three of them zoonotic) that are currently emerging in new geographical locations: Rift Valley fever virus (RVFV), Crimean‐Congo haemorrhagic fever virus (CCHFV), Schmallenberg virus (SBV), Bluetongue virus (BTV) and the bacteria complex Mycobacterium tuberculosis. Using the Luminex platform, polystyrene microspheres were coated with recombinant proteins from each of the five pathogens. The mix of microspheres was used for the simultaneous detection of antibodies against the five corresponding diseases affecting ruminants. The following panel of sera was included in the study: 50 sera from sheep experimentally infected with RVFV, 74 sera from calves and lambs vaccinated with SBV, 26 sera from cattle vaccinated with Mycobacterium bovis, 30 field sera from different species of ruminants infected with CCHFV and 88 calf sera infected with BTV. Finally, to determine its diagnostic specificity 220 field sera from Spanish farms free of the five diseases were assessed. All the sera were classified using commercial ELISAs specific for each disease, used in this study as the reference technique. The results showed the multiplex assay exhibited good performance characteristics with values of sensitivity ranging from 93% to 100% and of specificity ranging from 96% to 99% depending on the pathogen. This new tool allows the simultaneous detection of antibodies against five important pathogens, reducing the volume of sample needed and the time of analysis where these pathogens are usually tested individually.
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Affiliation(s)
- Alexis C R Hoste
- Eurofins-Inmunología y Genética Aplicada (Eurofins-INGENASA), Madrid, Spain.,School of Molecular and Cellular Biology, University of Leeds, Leeds, UK
| | - Tamara Ruiz
- Eurofins-Inmunología y Genética Aplicada (Eurofins-INGENASA), Madrid, Spain
| | - Paloma Fernández-Pacheco
- Centro de Investigación en Sanidad Animal - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA-CISA), Valdeolmos, Spain
| | - Miguel Ángel Jiménez-Clavero
- Centro de Investigación en Sanidad Animal - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA-CISA), Valdeolmos, Spain
| | - Igor Djadjovski
- Faculty of Veterinary Medicine, University Ss. Cyril & Methodius, Skopje, North Macedonia
| | - Sandra Moreno
- Centro de Investigación en Sanidad Animal - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA-CISA), Valdeolmos, Spain
| | - Alejandro Brun
- Centro de Investigación en Sanidad Animal - Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA-CISA), Valdeolmos, Spain
| | - Thomas A Edwards
- School of Molecular and Cellular Biology, University of Leeds, Leeds, UK
| | - John N Barr
- School of Molecular and Cellular Biology, University of Leeds, Leeds, UK
| | - Paloma Rueda
- Eurofins-Inmunología y Genética Aplicada (Eurofins-INGENASA), Madrid, Spain
| | - Patricia Sastre
- Eurofins-Inmunología y Genética Aplicada (Eurofins-INGENASA), Madrid, Spain
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14
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Ahmed A, Dietrich I, LaBeaud AD, Lindsay SW, Musa A, Weaver SC. Risks and Challenges of Arboviral Diseases in Sudan: The Urgent Need for Actions. Viruses 2020; 12:E81. [PMID: 31936607 PMCID: PMC7019415 DOI: 10.3390/v12010081] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Revised: 01/07/2020] [Accepted: 01/07/2020] [Indexed: 12/16/2022] Open
Abstract
The risk of emergence and/or re-emergence of arthropod-borne viral (arboviral) infections is rapidly growing worldwide, particularly in Africa. The burden of arboviral infections and diseases is not well scrutinized because of the inefficient surveillance systems in endemic countries. Furthermore, the health systems are fully occupied by the burden of other co-existing febrile illnesses, especially malaria. In this review we summarize the epidemiology and risk factors associated with the major human arboviral diseases and highlight the gap in knowledge, research, and control in Sudan. Published data in English up to March 2019 were reviewed and are discussed to identify the risks and challenges for the control of arboviruses in the country. In addition, the lack of suitable diagnostic tools such as viral genome sequencing, and the urgent need for establishing a genomic database of the circulating viruses and potential sources of entry are discussed. Moreover, the research and healthcare gaps and global health threats are analyzed, and suggestions for developing strategic health policy for the prevention and control of arboviruses with focus on building the local diagnostic and research capacity and establishing an early warning surveillance system for the early detection and containment of arboviral epidemics are offered.
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Affiliation(s)
- Ayman Ahmed
- Institute of Endemic Diseases, University of Khartoum, Khartoum 11111, Sudan
- Institute for Human Infections and Immunity, Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77755, USA
- World Reference Center for Emerging Viruses and Arboviruses, University of Texas Medical Branch, Galveston, TX 77755, USA
| | | | | | - Steve W. Lindsay
- Department of Biosciences, Durham University, Durham DH1 3LE, UK
| | - Ahmed Musa
- Institute of Endemic Diseases, University of Khartoum, Khartoum 11111, Sudan
| | - Scott C. Weaver
- Institute for Human Infections and Immunity, Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, TX 77755, USA
- World Reference Center for Emerging Viruses and Arboviruses, University of Texas Medical Branch, Galveston, TX 77755, USA
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15
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Shoemaker TR, Nyakarahuka L, Balinandi S, Ojwang J, Tumusiime A, Mulei S, Kyondo J, Lubwama B, Sekamatte M, Namutebi A, Tusiime P, Monje F, Mayanja M, Ssendagire S, Dahlke M, Kyazze S, Wetaka M, Makumbi I, Borchert J, Zufan S, Patel K, Whitmer S, Brown S, Davis WG, Klena JD, Nichol ST, Rollin PE, Lutwama J. First Laboratory-Confirmed Outbreak of Human and Animal Rift Valley Fever Virus in Uganda in 48 Years. Am J Trop Med Hyg 2020; 100:659-671. [PMID: 30675833 PMCID: PMC6402942 DOI: 10.4269/ajtmh.18-0732] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
In March 2016, an outbreak of Rift Valley fever (RVF) was identified in Kabale district, southwestern Uganda. A comprehensive outbreak investigation was initiated, including human, livestock, and mosquito vector investigations. Overall, four cases of acute, nonfatal human disease were identified, three by RVF virus (RVFV) reverse transcriptase polymerase chain reaction (RT-PCR), and one by IgM and IgG serology. Investigations of cattle, sheep, and goat samples from homes and villages of confirmed and probable RVF cases and the Kabale central abattoir found that eight of 83 (10%) animals were positive for RVFV by IgG serology; one goat from the home of a confirmed case tested positive by RT-PCR. Whole genome sequencing from three clinical specimens was performed and phylogenetic analysis inferred the relatedness of 2016 RVFV with the 2006–2007 Kenya-2 clade, suggesting previous introduction of RVFV into southwestern Uganda. An entomological survey identified three of 298 pools (1%) of Aedes and Coquillettidia species that were RVFV positive by RT-PCR. This was the first identification of RVFV in Uganda in 48 years and the 10th independent viral hemorrhagic fever outbreak to be confirmed in Uganda since 2010.
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Affiliation(s)
- Trevor R Shoemaker
- Viral Special Pathogens Branch, Centers for Disease Control and Prevention, Atlanta, Georgia.,Viral Special Pathogens Branch, Centers for Disease Control and Prevention-Uganda, Entebbe, Uganda
| | - Luke Nyakarahuka
- Department of Biosecurity, Ecosystems and Veterinary Public Health, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala, Uganda.,Department of Arbovirology, Emerging and Reemerging Infectious Diseases, Uganda Virus Research Institute, Entebbe, Uganda
| | - Stephen Balinandi
- Viral Special Pathogens Branch, Centers for Disease Control and Prevention-Uganda, Entebbe, Uganda
| | - Joseph Ojwang
- Global Health Security Unit, Centers for Disease Control and Prevention-Uganda, Kampala, Uganda
| | - Alex Tumusiime
- Viral Special Pathogens Branch, Centers for Disease Control and Prevention-Uganda, Entebbe, Uganda
| | - Sophia Mulei
- Department of Arbovirology, Emerging and Reemerging Infectious Diseases, Uganda Virus Research Institute, Entebbe, Uganda
| | - Jackson Kyondo
- Department of Biosecurity, Ecosystems and Veterinary Public Health, College of Veterinary Medicine, Animal Resources and Biosecurity, Makerere University, Kampala, Uganda
| | | | | | | | | | - Fred Monje
- Ministry of Agriculture, Animal Industry and Fisheries, Kampala, Uganda
| | - Martin Mayanja
- Department of Arbovirology, Emerging and Reemerging Infectious Diseases, Uganda Virus Research Institute, Entebbe, Uganda
| | | | - Melissa Dahlke
- Public Health Emergency Operations Centre, Ministry of Health, Kampala, Uganda
| | - Simon Kyazze
- Public Health Emergency Operations Centre, Ministry of Health, Kampala, Uganda
| | - Milton Wetaka
- Public Health Emergency Operations Centre, Ministry of Health, Kampala, Uganda
| | - Issa Makumbi
- Public Health Emergency Operations Centre, Ministry of Health, Kampala, Uganda
| | - Jeff Borchert
- Global Health Security Unit, Centers for Disease Control and Prevention-Uganda, Kampala, Uganda
| | - Sara Zufan
- Viral Special Pathogens Branch, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Ketan Patel
- Viral Special Pathogens Branch, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Shannon Whitmer
- Viral Special Pathogens Branch, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Shelley Brown
- Viral Special Pathogens Branch, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - William G Davis
- Viral Special Pathogens Branch, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - John D Klena
- Viral Special Pathogens Branch, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Stuart T Nichol
- Viral Special Pathogens Branch, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Pierre E Rollin
- Viral Special Pathogens Branch, Centers for Disease Control and Prevention, Atlanta, Georgia
| | - Julius Lutwama
- Department of Arbovirology, Emerging and Reemerging Infectious Diseases, Uganda Virus Research Institute, Entebbe, Uganda
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16
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Rissmann M, Stoek F, Pickin MJ, Groschup MH. Mechanisms of inter-epidemic maintenance of Rift Valley fever phlebovirus. Antiviral Res 2019; 174:104692. [PMID: 31870761 DOI: 10.1016/j.antiviral.2019.104692] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2019] [Revised: 09/26/2019] [Accepted: 12/11/2019] [Indexed: 12/31/2022]
Abstract
Rift Valley fever phlebovirus (RVFV) is an arthropod-borne virus that has caused substantial epidemics throughout Africa and in the Arabian Peninsula. The virus can cause severe disease in livestock and humans and therefore the control and prevention of viral outbreaks is of utmost importance. The epidemiology of RVFV has some particular characteristics. Unexpected and significant epidemics have been observed in spatially and temporally divergent patterns across the African continent. Sudden epidemics in previously unaffected areas are followed by periods of long-term apparent absence of virus and sudden, unpredictable reoccurrence in disparate regions. Therefore, the elucidation of underlying mechanisms of viral maintenance is one of the largest gaps in the knowledge of RVFV ecology. It remains unknown whether the virus needs to be reintroduced before RVF outbreaks can occur, or if unperceived viral circulation in local vertebrates or mosquitoes is sufficient for maintenance of the virus. To gain insight into these knowledge gaps, we here review existing data that describe potential mechanisms of RVFV maintenance, as well as molecular and serological studies in endemic and non-endemic areas that provide evidence of an inter- or pre-epidemic virus presence. Basic and country-specific mechanisms of RVFV introduction into non-endemic countries are summarized and an overview of studies using mathematical modeling of RVFV persistence is given.
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Affiliation(s)
- Melanie Rissmann
- Friedrich-Loeffler-Institut, Institute of Novel and Emerging Infectious Diseases, Suedufer 10, 17489, Greifswald-Insel Riems, Germany
| | - Franziska Stoek
- Friedrich-Loeffler-Institut, Institute of Novel and Emerging Infectious Diseases, Suedufer 10, 17489, Greifswald-Insel Riems, Germany
| | - Matthew J Pickin
- Friedrich-Loeffler-Institut, Institute of Novel and Emerging Infectious Diseases, Suedufer 10, 17489, Greifswald-Insel Riems, Germany
| | - Martin H Groschup
- Friedrich-Loeffler-Institut, Institute of Novel and Emerging Infectious Diseases, Suedufer 10, 17489, Greifswald-Insel Riems, Germany.
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17
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Kardjadj M, Diallo A, Lancelot R. TADs in the Dromedary. TRANSBOUNDARY ANIMAL DISEASES IN SAHELIAN AFRICA AND CONNECTED REGIONS 2019. [PMCID: PMC7122668 DOI: 10.1007/978-3-030-25385-1_6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Moustafa Kardjadj
- Ecole Supérieure en Science de l’Aliment et des Industries Agro-Alimentaire, Algiers, Algeria; Laboratoire de Recherche «Santé et Productions Animales», Ecole Nationale Supérieure Vétérinaire d’Alger (ENSV), El-Alia, Algiers, Algeria
| | - Adama Diallo
- UMR ASTRE, CIRAD, Montpellier, France; ASTRE, Montpellier University, CIRAD, INRA, Montpellier, France, ISRA-LNERV, Dakar-Hann, Senegal
| | - Renaud Lancelot
- UMR ASTRE, CIRAD, Montpellier, France; ASTRE, Montpellier University, CIRAD, INRA, Montpellier, France
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18
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Mohamed N, Magzoub M, Mohamed REH, Aleanizy FS, Alqahtani FY, Nour BYM, Alkarsany MMS. Prevalence and identification of arthropod-transmitted viruses in Kassala state, Eastern Sudan. Libyan J Med 2019. [PMID: 30716013 PMCID: PMC6366427 DOI: 10.1080/19932820.2018.1564511] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Vector-borne diseases are responsible for more than 20% of the infectious diseases worldwide. The prevalence of arboviruses transmit diseases to humans in Sudan has not been investigated. Mosquito-borne viral diseases increase globally incidence, including the Sudan. Frequent unknown fever outbreaks have been reported in eastern region, Sudan. However, diagnosis was based exclusively on clinical signs and symptoms without confirmatory laboratory investigations. However, for accurate detection of these viruses in outbreaks, molecular technique is considered. The objective of this study was to determine the prevalence of six arboviruses in the Kassala state of east Sudan during unknown fever outbreak. A cross sectional hospital-based study was conducted in the Kassala, Teaching Hospital. Blood samples from 119 patients suffering from unknown fever were used for screening of six arboviruses, hepatitis E virus and malarial using molecular techniques and serology. The overall arboviruses seroprevelance was 61.3% (73/119). The highest positivity rate was 73.1% (52/73) chikungunya virus; 29 males and 20 females patients were chikungunya positive. Other arboviruses were circulating in low rate 20.5% (15/73), and 6.8% (5/73) for sindbis and rift valley fever viruses respectively. Hepatitis E virus was negative in all cases and malaria positivity rate 13.4% (16/119). The prevalence of arboviruses among unknown fever patients present to Kassala teaching hospital of eastern region in Sudan is significantly high (61.3%). The chikungunya virus is the predominant causative agent of arboviruses. Molecular techniques such as PCR are important for accurate and rapid diagnosis of this viral outbreak.
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Affiliation(s)
- Nahla Mohamed
- a Faculty of Medical Laboratory Sciences , Karrary University , Omdurman , Sudan.,b Faculty of Medicine , University of Kassala, Kassala , Sudan
| | - Mamoun Magzoub
- c College of Medicine , Princess Nourah bint Abdulrahman University , Riyadh , Saudi Arabia.,d Clinical Microbiology Department, Virology Unit , Umeå university , Umeå , Sweden
| | - Rania El Hadi Mohamed
- e College of Science , Princess Nourah bint Abdulrahman University , Riyadh , Saudi Arabia.,f Federal Ministry of Health , Khartoum , Sudan
| | - Fadilah Sfouq Aleanizy
- g Department of Pharmaceutics, College of Pharmacy , King Saud University , Riyadh , Saudi Arabia
| | - Fulwah Y Alqahtani
- g Department of Pharmaceutics, College of Pharmacy , King Saud University , Riyadh , Saudi Arabia
| | - Bakri Y M Nour
- h Blue Nile National Institute for Communicable Diseases , University of Gezira , Wad Medani , Sudan.,i Department of Parasitology , University of Gezira , Wad Medani , Sudan
| | - Mubark M S Alkarsany
- c College of Medicine , Princess Nourah bint Abdulrahman University , Riyadh , Saudi Arabia
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Budasha NH, Gonzalez JP, Sebhatu TT, Arnold E. Rift Valley fever seroprevalence and abortion frequency among livestock of Kisoro district, South Western Uganda (2016): a prerequisite for zoonotic infection. BMC Vet Res 2018; 14:271. [PMID: 30176865 PMCID: PMC6122569 DOI: 10.1186/s12917-018-1596-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Accepted: 08/24/2018] [Indexed: 11/25/2022] Open
Abstract
Background Rift Valley fever (RVF) is classified as viral hemorrhagic fever and is endemic in East and West Africa. RVF is caused by an arthropod borne virus (RVFV); the disease is zoonotic and affects human, animal health as well as international trade. In livestock it causes abortions, while human infection occurs through close contact with infected animals or animal products. Methods A quantitative observational study using stratified sampling was conducted in the western region of Uganda. Blood samples and abortion events from 1000 livestock (goats, sheep and cattle) was collected and recorded. Serum was analyzed for RVFV IgG reacting antibodies using competitive ELISA test. Results The overall RVFV seroprevalence was of 10.4% (104/1000). Cattle had the highest seroprevalence (7%) followed by Sheep (2.2%) then goats (1.2%). Species specific RVFV seroprevalence was highest in cattle (20.5%) followed by sheep (6.8%) then goats (3.6%). RVFV seroprevalence in northern highlands (21.8%) was significantly higher (p < 0.001) than in the southern lowlands (3.7%). Overall prevalence of abortion was (17.4%), sheep had the highest prevalence of abortion (7.8%) followed by goats (6.3%) and then cattle (3.3%). Species specific abortion prevalence was highest in Sheep (24.1%) followed by goats (18.8%) and then 9.7% in cattle. Conclusion RVFV is endemic in Kisoro district and livestock in the highland areas are more likely to be exposed to RVFV infection compared to those in the southern lowlands. Out breaks in livestock most likely will lead to zoonotic infection in Kisoro district.
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Affiliation(s)
- Ngabo Herbert Budasha
- Kisoro District Local Government, Department of Production and Marketing, Office of the District Veterinary Officer, P.O Box 123, Kisoro, Uganda
| | - Jean-Paul Gonzalez
- Center of Excellence for Emerging & Zoonotic Animal Disease (CEEZAD) Kansas State University, Office Park, 1800 Kimball Ave, Suite 130, Manhattan, KS, 66502, USA
| | - Tesfaalem Tekleghiorghis Sebhatu
- College of Veterinary Medicine, International Programs, Kansas State University, Office Park, 1800 Kimball Ave, Suite 180, Manhattan, KS, 66502, USA
| | - Ezama Arnold
- Department of Health and Social services, Uganda Red Cross Society, P.O.Box 494, Kampala, Uganda.
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Eldigail MH, Adam GK, Babiker RA, Khalid F, Adam IA, Omer OH, Ahmed ME, Birair SL, Haroun EM, AbuAisha H, Karrar AE, Abdalla HS, Aradaib IE. Prevalence of dengue fever virus antibodies and associated risk factors among residents of El-Gadarif state, Sudan. BMC Public Health 2018; 18:921. [PMID: 30053811 PMCID: PMC6062928 DOI: 10.1186/s12889-018-5853-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2017] [Accepted: 07/17/2018] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND Dengue fever, caused by dengue virus (DENV), has become one of the most important mosquito-borne viral diseases with a steady rise in global incidence, including the Sudan. Sporadic cases and frequent acute febrile illness outbreaks, compatible with Dengue fever, have been reported in El-Gadarif State, Sudan. However, diagnosis was based almost exclusively on clinical signs without confirmatory laboratory investigations. Despite the magnitude of the problem in El-Gadarif State, no information is currently available with regard to the epidemiology of the disease in this State. El-Gadarif State is one of the largest commercial centers in the Sudan. The objective of the present investigation is to estimate the prevalence of DENV antibodies, and determine the potential risk factors associated with seropositivity among residents of El-Gadarif State. METHODS A cross sectional study was conducted in a total of 701residents randomly selected from all 10 localities in El-Gadarif State. The sera from the 701 residents were tested for the presence of DENV-specific immunoglobulin G (IgG) antibodies using a commercially available Anti-dengue IgG enzyme-linked immunosorbent assay (ELISA). RESULTS Among the 701 residents, 334 residents (47.6%) were seropositive for DENV. Mosquito control (OR = 2.73, CI = 1.37-5.87, p-value = 0.001); low income (OR = 2.31, CI: 1.71-6.36, p value = 0.032); sleeping out-doors (OR = 3.73, CI = 2.63-6.23, p-value = 0.013), and localities were determined as potential risk factors for contracting DENV infection. CONCLUSIONS The prevalence rate of DENV antibodies among residents of El-Gadarif State is significantly high (47.6%). Further epidemiologic studies including, distribution of mosquito vectors and implementation of improved surveillance are urgently warranted for better prediction and prevention of a possible DENV outbreak in El-Gadarif State, Sudan.
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Affiliation(s)
- Mawahib H. Eldigail
- 0000 0001 0674 6207grid.9763.bMolecular Biology Laboratory (MBL), Department of Clinical Medicine, Faculty of Veterinary Medicine, University of Khartoum, P.O. Box 32, Khartoum North, Sudan
| | - Gamal K. Adam
- Department of Medical laboratory Sciences, Faculty of Medicine, University of Elgadarif, Elgadarif, Sudan
| | - Rabie A. Babiker
- Department of Medical laboratory Sciences, Faculty of Medicine, University of Elgadarif, Elgadarif, Sudan
| | - Fatima Khalid
- 0000 0004 0447 6858grid.412060.1Department of Microbiology, Faculty of Science, University of Kassala, Kassala, Sudan
| | - Ibrahim A. Adam
- 0000 0001 0674 6207grid.9763.bMolecular Biology Laboratory (MBL), Department of Clinical Medicine, Faculty of Veterinary Medicine, University of Khartoum, P.O. Box 32, Khartoum North, Sudan
| | - Osama H. Omer
- 0000 0001 0674 6207grid.9763.bMolecular Biology Laboratory (MBL), Department of Clinical Medicine, Faculty of Veterinary Medicine, University of Khartoum, P.O. Box 32, Khartoum North, Sudan
| | - Mohamed E. Ahmed
- grid.440839.2Deanship of Scientific research, Alneelain University, Khartoum, Sudan
| | - Sara L. Birair
- grid.440839.2Deanship of Scientific research, Alneelain University, Khartoum, Sudan
| | - Eltahir M. Haroun
- grid.442398.0Deanship of Scientific research, International University of Africa, Khartoum, Sudan
| | - Hassan AbuAisha
- grid.442398.0Deanship of Scientific research, International University of Africa, Khartoum, Sudan
| | - Abdelrahim E. Karrar
- 0000 0001 0674 6207grid.9763.bMolecular Biology Laboratory (MBL), Department of Clinical Medicine, Faculty of Veterinary Medicine, University of Khartoum, P.O. Box 32, Khartoum North, Sudan
| | - Hamid S. Abdalla
- 0000 0001 0674 6207grid.9763.bMolecular Biology Laboratory (MBL), Department of Clinical Medicine, Faculty of Veterinary Medicine, University of Khartoum, P.O. Box 32, Khartoum North, Sudan
| | - Imadeldin E. Aradaib
- 0000 0001 0674 6207grid.9763.bMolecular Biology Laboratory (MBL), Department of Clinical Medicine, Faculty of Veterinary Medicine, University of Khartoum, P.O. Box 32, Khartoum North, Sudan
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Mahmoud AS, Di Sabatino D, Danzetta ML, Iapaolo F, Tolari F, Forzan M, Mazzei M, Dayhum A, De Massis F, Monaco F. Rift Valley fever virus: a serological survey in Libyan ruminants. Open Vet J 2018; 8:204-207. [PMID: 30425953 PMCID: PMC6202668 DOI: 10.4314/ovj.v8i2.15] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2018] [Accepted: 05/28/2018] [Indexed: 12/26/2022] Open
Abstract
A serological survey was carried out in Libya to investigate the circulation of Rift Valley fever virus (RVFV) among domestic ruminants. A total of 857 serum samples were collected from year 2015 to 2016 in eleven provinces of Libya belonging to five branches of the country. Samples were tested for RVFV antibodies using a competitive Enzyme-Linked Immunosorbent Assay (c-ELISA). Antibodies specific for RVFV were not detected in any of the 857 samples. However, a statistical analysis was carried out to assess the maximum expected number of infected animals and the maximum expected prevalence of RVFV among Libyan ruminants' populations according to the sampled population. The overall maximum expected prevalence was estimated to be 1.8% for cattle and 0.4% for small ruminants. Results seem to exclude the circulation of RVFV, however, a surveillance plan should be implemented in areas at risk of RVFV introduction.
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Affiliation(s)
- Abdusalam Sharef Mahmoud
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise "G. Caporale", (IZSAM), Teramo, Italy.,Department of Preventive Medicine, Faculty of Veterinary Medicine, University of Tripoli, Tripoli, Libya.,Department of Veterinary Science, University of Pisa, Pisa, Italy
| | - Daria Di Sabatino
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise "G. Caporale", (IZSAM), Teramo, Italy
| | - Maria Luisa Danzetta
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise "G. Caporale", (IZSAM), Teramo, Italy
| | - Federica Iapaolo
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise "G. Caporale", (IZSAM), Teramo, Italy
| | - Francesco Tolari
- Department of Veterinary Science, University of Pisa, Pisa, Italy
| | - Mario Forzan
- Department of Veterinary Science, University of Pisa, Pisa, Italy
| | - Maurizio Mazzei
- Department of Veterinary Science, University of Pisa, Pisa, Italy
| | - Abdunaser Dayhum
- Department of Preventive Medicine, Faculty of Veterinary Medicine, University of Tripoli, Tripoli, Libya.,National Center of Animal Health, Tripoli, Libya
| | - Fabrizio De Massis
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise "G. Caporale", (IZSAM), Teramo, Italy
| | - Federica Monaco
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise "G. Caporale", (IZSAM), Teramo, Italy
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Kenawy MA, Abdel-Hamid YM, Beier JC. Rift Valley Fever in Egypt and other African countries: Historical review, recent outbreaks and possibility of disease occurrence in Egypt. Acta Trop 2018; 181:40-49. [PMID: 29391128 DOI: 10.1016/j.actatropica.2018.01.015] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 01/03/2018] [Accepted: 01/23/2018] [Indexed: 01/09/2023]
Abstract
This article reviews and discusses the historical and recent status of Rift Valley Fever (RVF) in Egypt and the other African countries based on the available and scattered reports. The recent outbreaks in African countries were reviewed and mapped out. Four major epidemics have been recorded in Egypt (1977, 1978, 1993 and 2003). The outbreak resulted in unpredicted human disease with severe clinical manifestations and heavy mortality as well as many abortions and deaths in sheep, goats, cattle, water buffalo and camels. Of the 18 culicine mosquito species that occur in Egypt, Culex pipiens and Cx. antennatus were implicated as vectors of RVF in Egypt based on their natural infection with RVF virus. Aedes caspius was also suspected of disseminating the virus among livestock based on host feeding and vector competence studies. The epidemiological factors related to the introduction and spread of RVF in Egypt are discussed. The study concluded that due to the availability and abundance of the potential vectors, suitability of environmental conditions, continuous importation of livestock's from Sudan, and the close association of susceptible domestic animals with humans, the RVF virus could possibly occur and circulate in Egypt.
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23
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Napp S, Chevalier V, Busquets N, Calistri P, Casal J, Attia M, Elbassal R, Hosni H, Farrag H, Hassan N, Tawfik R, Abd Elkader S, Bayomy S. Understanding the legal trade of cattle and camels and the derived risk of Rift Valley Fever introduction into and transmission within Egypt. PLoS Negl Trop Dis 2018; 12:e0006143. [PMID: 29351273 PMCID: PMC5792020 DOI: 10.1371/journal.pntd.0006143] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Revised: 01/31/2018] [Accepted: 11/29/2017] [Indexed: 12/25/2022] Open
Abstract
Rift Valley Fever (RVF) is a mosquito-borne zoonosis, which may cause significant losses for the livestock sector and have serious public health implications. Egypt has been repeatedly affected by RVF epidemics, mainly associated to the importation of animals from sub-Saharan countries, where the disease is endemic. The objective of our study was the improvement of the surveillance and control strategies implemented in Egypt. In order to do that, first we evaluated the legal trade of live animals into and within Egypt. Then, we assessed the risk of Rift Valley Fever virus (RVFV) transmission within the country using a multi-criteria evaluation approach. Finally, we combined the animal trade and the risk of RVFV transmission data to identify those areas and periods in which the introduction of RVFV is more likely. Our results indicate that the main risk of RVFV introduction is posed by the continuous flow of large number of camels coming from Sudan. The risk of RVFV transmission by vectors is restricted to the areas surrounding the Nile river, and does not vary significantly throughout the year. Imported camels are taken to quarantines, where the risk of RVFV transmission by vectors is generally low. Then, they are taken to animal markets or slaughterhouses, many located in populated areas, where the risk of RVFV transmission to animals or humans is much higher. The measures currently implemented (quarantines, vaccination or testing) seem to have a limited effect in reducing the risk of RVFV introduction, and therefore other (risk-based) surveillance strategies are proposed.
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Affiliation(s)
| | | | | | - Paolo Calistri
- Food and Agriculture Organization of the United Nations (FAO), Rome, Italy
- IZSAM, Teramo, Italy
| | - Jordi Casal
- CReSA-IRTA, Barcelona, Spain
- UAB, Barcelona, Spain
| | - Mohamed Attia
- Central Administration of Preventive Medicine. Ministry of Agriculture and Land Reclamation, Cairo, Egypt
| | - Rehab Elbassal
- Department of Epidemiology. Ministry of Agriculture and Land Reclamation, Cairo, Egypt
| | - Heba Hosni
- Department of Epidemiology. Ministry of Agriculture and Land Reclamation, Cairo, Egypt
| | - Hatem Farrag
- Quarantine & Inspection Department. Ministry of Agriculture and Land Reclamation, Cairo, Egypt
| | - Noura Hassan
- Quarantine & Inspection Department. Ministry of Agriculture and Land Reclamation, Cairo, Egypt
| | - Rasha Tawfik
- Quarantine & Inspection Department. Ministry of Agriculture and Land Reclamation, Cairo, Egypt
| | - Sohair Abd Elkader
- Central Administration of Preventive Medicine. Ministry of Agriculture and Land Reclamation, Cairo, Egypt
| | - Shahin Bayomy
- Department of Epidemiology. Ministry of Agriculture and Land Reclamation, Cairo, Egypt
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24
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Mweya CN, Mboera LEG, Kimera SI. Climate Influence on Emerging Risk Areas for Rift Valley Fever Epidemics in Tanzania. Am J Trop Med Hyg 2017; 97:109-114. [PMID: 28719317 DOI: 10.4269/ajtmh.16-0444] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Rift Valley Fever (RVF) is a climate-related arboviral infection of animals and humans. Climate is thought to represent a threat toward emerging risk areas for RVF epidemics globally. The objective of this study was to evaluate influence of climate on distribution of suitable breeding habitats for Culex pipiens complex, potential mosquito vector responsible for transmission and distribution of disease epidemics risk areas in Tanzania. We used ecological niche models to estimate potential distribution of disease risk areas based on vectors and disease co-occurrence data approach. Climatic variables for the current and future scenarios were used as model inputs. Changes in mosquito vectors' habitat suitability in relation to disease risk areas were estimated. We used partial receiver operating characteristic and the area under the curves approach to evaluate model predictive performance and significance. Habitat suitability for Cx. pipiens complex indicated broad-scale potential for change and shift in the distribution of the vectors and disease for both 2020 and 2050 climatic scenarios. Risk areas indicated more intensification in the areas surrounding Lake Victoria and northeastern part of the country through 2050 climate scenario. Models show higher probability of emerging risk areas spreading toward the western parts of Tanzania from northeastern areas and decrease in the southern part of the country. Results presented here identified sites for consideration to guide surveillance and control interventions to reduce risk of RVF disease epidemics in Tanzania. A collaborative approach is recommended to develop and adapt climate-related disease control and prevention strategies.
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Affiliation(s)
- Clement N Mweya
- Tukuyu Research Centre, National Institute for Medical Research, Tukuyu, Tanzania
| | - Leonard E G Mboera
- Headquarters, National Institute for Medical Research, Dar es salaam, Tanzania
| | - Sharadhuli I Kimera
- Department of Veterinary Medicine and Public Health, Sokoine University of Agriculture, Morogoro, Tanzania
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25
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Mroz C, Gwida M, El-Ashker M, El-Diasty M, El-Beskawy M, Ziegler U, Eiden M, Groschup MH. Seroprevalence of Rift Valley fever virus in livestock during inter-epidemic period in Egypt, 2014/15. BMC Vet Res 2017; 13:87. [PMID: 28381251 PMCID: PMC5382484 DOI: 10.1186/s12917-017-0993-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2016] [Accepted: 03/17/2017] [Indexed: 11/25/2022] Open
Abstract
Background Rift Valley fever virus (RVFV) caused several outbreaks throughout the African continent and the Arabian Peninsula posing significant threat to human and animal health. In Egypt the first and most important Rift Valley fever epidemic occurred during 1977/78 with a multitude of infected humans and huge economic losses in livestock. After this major outbreak, RVF epidemics re-occurred in irregular intervals between 1993 and 2003. Seroprevalence of anti-RVFV antibodies in livestock during inter-epidemic periods can be used for supporting the evaluation of the present risk exposure for animal and public health. A serosurvey was conducted during 2014/2015 in non-vaccinated livestock including camels, sheep, goats and buffalos in different areas of the Nile River Delta as well as the furthermost southeast of Egypt to investigate the presence of anti-RVFV antibodies for further evaluating of the risk exposure for animal and human health. All animals integrated in this study were born after the last Egyptian RVF epidemic in 2003 and sampled buffalos and small ruminants were not imported from other endemic countries. Results A total of 873 serum samples from apparently healthy animals from different host species (camels: n = 221; sheep: n = 438; goats: n = 26; buffalo: n = 188) were tested serologically using RVFV competition ELISA, virus neutralization test and/or an indirect immunofluorescence assay, depending on available serum volume. Sera were assessed positive when virus neutralization test alone or least two assays produced consistent positive results. The overall seroprevalence was 2.29% (95%CI: 1.51–3.07) ranging from 0% in goats, 0.46% in sheep (95%CI: 0.41–0.5), and 3.17% in camels (95%CI: 0.86–5.48) up to 5.85% in buffalos (95%CI: 2.75–8.95). Conclusion Our findings assume currently low level of circulating virus in the investigated areas and suggest minor indication for a new RVF epidemic. Further the results may indicate that during long inter-epidemic periods, maintenance of the virus occur in vectors and also most probably in buffaloes within cryptic cycle where sporadic, small and local epidemics may occur. Therefore, comprehensive and well-designed surveillance activities are urgently needed to detect first evidence for transition from endemic to epidemic cycle. Electronic supplementary material The online version of this article (doi:10.1186/s12917-017-0993-8) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Claudia Mroz
- Institute of Novel and Emerging Infectious Diseases, Friedrich-Loeffler-Institut, Südufer 10, 17493, Greifswald - Isle of Riems, Germany
| | - Mayada Gwida
- Department of Hygiene and Zoonoses, Faculty of Veterinary Medicine, Mansoura University, Mansoura, 35516, Egypt
| | - Maged El-Ashker
- Department of Internal Medicine and Infectious Diseases, Faculty of Veterinary Medicine, Mansoura University, Mansoura, 35516, Egypt
| | - Mohamed El-Diasty
- Animal Health Research Institute-Mansoura Provincial Laboratory, Mansoura, Egypt
| | | | - Ute Ziegler
- Institute of Novel and Emerging Infectious Diseases, Friedrich-Loeffler-Institut, Südufer 10, 17493, Greifswald - Isle of Riems, Germany
| | - Martin Eiden
- Institute of Novel and Emerging Infectious Diseases, Friedrich-Loeffler-Institut, Südufer 10, 17493, Greifswald - Isle of Riems, Germany
| | - Martin H Groschup
- Institute of Novel and Emerging Infectious Diseases, Friedrich-Loeffler-Institut, Südufer 10, 17493, Greifswald - Isle of Riems, Germany.
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Samy AM, Peterson AT, Hall M. Phylogeography of Rift Valley Fever Virus in Africa and the Arabian Peninsula. PLoS Negl Trop Dis 2017; 11:e0005226. [PMID: 28068340 PMCID: PMC5221768 DOI: 10.1371/journal.pntd.0005226] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2016] [Accepted: 12/01/2016] [Indexed: 01/31/2023] Open
Abstract
Rift Valley Fever is an acute zoonotic viral disease caused by Rift Valley Fever virus (RVFV) that affects ruminants and humans in Sub-Saharan Africa and the Arabian Peninsula. We used phylogenetic analyses to understand the demographic history of RVFV populations, using sequence data from the three minigenomic segments of the virus. We used phylogeographic approaches to infer RVFV historical movement patterns across its geographic range, and to reconstruct transitions among host species. Results revealed broad circulation of the virus in East Africa, with many lineages originating in Kenya. Arrival of RVFV in Madagascar resulted from three major waves of virus introduction: the first from Zimbabwe, and the second and third from Kenya. The two major outbreaks in Egypt since 1977 possibly resulted from a long-distance introduction from Zimbabwe during the 1970s, and a single introduction took RVFV from Kenya to Saudi Arabia. Movement of the virus between Kenya and Sudan, and CAR and Zimbabwe, was in both directions. Viral populations in West Africa appear to have resulted from a single introduction from Central African Republic. The overall picture of RVFV history is thus one of considerable mobility, and dynamic evolution and biogeography, emphasizing its invasive potential, potentially more broadly than its current distributional limits. Rift Valley Fever is an acute zoonotic viral disease caused by Rift Valley Fever virus (RVFV) that affects ruminants and humans in Sub-Saharan Africa and the Arabian Peninsula. We used phylogenetic approaches that take sampling date into account to understand the demographic history of RVFV populations, using sequence data from the three minigenomic segments of the virus. We found evidence of broad circulation of the virus in East Africa, with many lineages originating in Kenya, with single and multiple introductions of RVFV among countries. The overall picture of RVFV history is thus one of considerable mobility, and dynamic evolution and biogeography, emphasizing its invasive potential, potentially more broadly than its current distributional limits.
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Affiliation(s)
- Abdallah M. Samy
- Biodiversity Institute, University of Kansas, Lawrence, Kansas, United States of America
- Entomology Department, Faculty of Science, Ain Shams University, Abbassia, Cairo, Egypt
- * E-mail: ,
| | - A. Townsend Peterson
- Biodiversity Institute, University of Kansas, Lawrence, Kansas, United States of America
| | - Matthew Hall
- Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, United Kingdom
- Centre for Immunity, Infection and Evolution, University of Edinburgh, Edinburgh, United Kingdom
- Department of Infectious Disease Epidemiology, Imperial College London, London, United Kingdom
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Enkhtsetseg A, Davadoorj R, Fernandez S, Mongkolsirichaikul D, Altantuul D, Elbegdorj E, Ganchimeg L, Yingst SL. Seroconversion to Causes of Febrile Illness in Mongolian Peacekeepers Deployed to South Sudan. Am J Trop Med Hyg 2016; 95:1469-1471. [PMID: 27928094 DOI: 10.4269/ajtmh.16-0174] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Accepted: 07/20/2016] [Indexed: 11/07/2022] Open
Abstract
Immediately before deployment (Fall 2012) and after deployment (Spring 2013) in support of United Nations peacekeeping operations, Mongolian Armed Forces medical personnel obtained serum samples from the first contingent of Mongolian peacekeepers deploying to South Sudan to monitor serologic evidence of exposure to diseases that cause acute febrile illness. A total of 632 paired samples were tested for IgG antibody for the following (number of seroconversions in parentheses): Rickettsia (spotted fever and typhus groups) (25), West Nile fever virus (WNV) (23), Coxiella burnetii (causative agent of Q fever) (12), dengue virus (8), leptospirosis (6), chikungunya virus (0), Congo-Crimean hemorrhagic fever virus (0), Japanese encephalitis virus (0), and Rift Valley fever virus (0). There was also evidence of exposure to WNV, C. burnetii, leptospirosis, and Rickettsia before deployment.
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Affiliation(s)
| | | | - Stefan Fernandez
- U.S. Army Medical Research Acquisition Authority, Fort Detrick, Maryland
| | | | | | - Erdene Elbegdorj
- Blavatnik School of Government, University of Oxford, Oxford, United Kingdom
| | | | - Samuel L Yingst
- Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand. .,Purdue University College of Veterinary Medicine, West Lafayette, Indiana
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Baudin M, Jumaa AM, Jomma HJE, Karsany MS, Bucht G, Näslund J, Ahlm C, Evander M, Mohamed N. Association of Rift Valley fever virus infection with miscarriage in Sudanese women: a cross-sectional study. LANCET GLOBAL HEALTH 2016; 4:e864-e871. [PMID: 27692776 DOI: 10.1016/s2214-109x(16)30176-0] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Revised: 06/27/2016] [Accepted: 07/14/2016] [Indexed: 12/14/2022]
Abstract
BACKGROUND Rift Valley fever virus is an emerging mosquito-borne virus that causes infections in animals and human beings in Africa and the Arabian Peninsula. Outbreaks of Rift Valley fever lead to mass abortions in livestock, but such abortions have not been identified in human beings. Our aim was to investigate the cause of miscarriages in febrile pregnant women in an area endemic for Rift Valley fever. METHODS Pregnant women with fever of unknown origin who attended the governmental hospital of Port Sudan, Sudan, between June 30, 2011, and Nov 17, 2012, were sampled at admission and included in this cross-sectional study. Medical records were retrieved and haematological tests were done on patient samples. Presence of viral RNA as well as antibodies against a variety of viruses were analysed. Any association of viral infections, symptoms, and laboratory parameters to pregnancy outcome was investigated using Pearson's χ2 test. FINDINGS Of 130 pregnant women with febrile disease, 28 were infected with Rift Valley fever virus and 31 with chikungunya virus, with typical clinical and laboratory findings for the infection in question. 15 (54%) of 28 women with an acute Rift Valley fever virus infection had miscarriages compared with 12 (12%) of 102 women negative for Rift Valley fever virus (p<0·0001). In a multiple logistic regression analysis, adjusting for age, haemorrhagic disease, and chikungunya virus infection, an acute Rift Valley fever virus infection was an independent predictor of having a miscarriage (odds ratio 7·4, 95% CI 2·7-20·1; p<0·0001). INTERPRETATION This study is the first to show an association between infection with Rift Valley fever virus and miscarriage in pregnant women. Further studies are warranted to investigate the possible mechanisms. Our findings have implications for implementation of preventive measures, and evidence-based information to the public in endemic countries should be strongly recommended during Rift Valley fever outbreaks. FUNDING Schlumberger Faculty for the Future, CRDF Global (31141), the Swedish International Development Cooperation Agency, the County Council of Västerbotten, and the Faculty of Medicine, Umeå University.
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Affiliation(s)
- Maria Baudin
- Department of Clinical Microbiology, Virology, Umeå University, Umeå, Sweden
| | - Ammar M Jumaa
- Department of Obstetrics and Gynaecology, Red Sea University, Port Sudan, Sudan
| | - Huda J E Jomma
- Department of Parasitology and Medical Entomology, Port Sudan Ahlia College, Port Sudan, Sudan
| | - Mubarak S Karsany
- Faculty of Medical Laboratory Sciences, Karary University, Khartoum, Sudan
| | - Göran Bucht
- Swedish Defence Research Agency, CBRN Defence and Security, Umeå, Sweden
| | - Jonas Näslund
- Swedish Defence Research Agency, CBRN Defence and Security, Umeå, Sweden
| | - Clas Ahlm
- Department of Clinical Microbiology, Infectious Diseases, Umeå University, Umeå, Sweden
| | - Magnus Evander
- Department of Clinical Microbiology, Virology, Umeå University, Umeå, Sweden.
| | - Nahla Mohamed
- Department of Clinical Microbiology, Virology, Umeå University, Umeå, Sweden
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Tran A, Trevennec C, Lutwama J, Sserugga J, Gély M, Pittiglio C, Pinto J, Chevalier V. Development and Assessment of a Geographic Knowledge-Based Model for Mapping Suitable Areas for Rift Valley Fever Transmission in Eastern Africa. PLoS Negl Trop Dis 2016; 10:e0004999. [PMID: 27631374 PMCID: PMC5025187 DOI: 10.1371/journal.pntd.0004999] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Accepted: 08/22/2016] [Indexed: 11/18/2022] Open
Abstract
Rift Valley fever (RVF), a mosquito-borne disease affecting ruminants and humans, is one of the most important viral zoonoses in Africa. The objective of the present study was to develop a geographic knowledge-based method to map the areas suitable for RVF amplification and RVF spread in four East African countries, namely, Kenya, Tanzania, Uganda and Ethiopia, and to assess the predictive accuracy of the model using livestock outbreak data from Kenya and Tanzania. Risk factors and their relative importance regarding RVF amplification and spread were identified from a literature review. A numerical weight was calculated for each risk factor using an analytical hierarchy process. The corresponding geographic data were collected, standardized and combined based on a weighted linear combination to produce maps of the suitability for RVF transmission. The accuracy of the resulting maps was assessed using RVF outbreak locations in livestock reported in Kenya and Tanzania between 1998 and 2012 and the ROC curve analysis. Our results confirmed the capacity of the geographic information system-based multi-criteria evaluation method to synthesize available scientific knowledge and to accurately map (AUC = 0.786; 95% CI [0.730-0.842]) the spatial heterogeneity of RVF suitability in East Africa. This approach provides users with a straightforward and easy update of the maps according to data availability or the further development of scientific knowledge.
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Affiliation(s)
- Annelise Tran
- CIRAD, UPR AGIRs, Ste-Clotilde, Reunion Island
- CIRAD, UMR TETIS, Ste-Clotilde, Reunion Island
| | - Carlène Trevennec
- Food and Agriculture Organization of the United Nations, Rome, Italy
| | | | - Joseph Sserugga
- Uganda Ministry of Agriculture, Animal Industry and Fisheries, Entebbe, Uganda
| | | | - Claudia Pittiglio
- Food and Agriculture Organization of the United Nations, Rome, Italy
| | - Julio Pinto
- Food and Agriculture Organization of the United Nations, Rome, Italy
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MAMAK N, BİLGİLİ İ. RİFT VADİSİ HUMMASI. MEHMET AKIF ERSOY ÜNIVERSITESI VETERINER FAKÜLTESI DERGISI 2016. [DOI: 10.24880/maeuvfd.260789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Baba M, Masiga DK, Sang R, Villinger J. Has Rift Valley fever virus evolved with increasing severity in human populations in East Africa? Emerg Microbes Infect 2016; 5:e58. [PMID: 27329846 PMCID: PMC4932650 DOI: 10.1038/emi.2016.57] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Revised: 03/08/2016] [Accepted: 03/16/2016] [Indexed: 11/19/2022]
Abstract
Rift Valley fever (RVF) outbreaks have occurred across eastern Africa from 1912 to 2010 approximately every 4–15 years, most of which have not been accompanied by significant epidemics in human populations. However, human epidemics during RVF outbreaks in eastern Africa have involved 478 deaths in 1998, 1107 reported cases with 350 deaths from 2006 to 2007 and 1174 cases with 241 deaths in 2008. We review the history of RVF outbreaks in eastern Africa to identify the epidemiological factors that could have influenced its increasing severity in humans. Diverse ecological factors influence outbreak frequency, whereas virus evolution has a greater impact on its virulence in hosts. Several factors could have influenced the lack of information on RVF in humans during earlier outbreaks, but the explosive nature of human RVF epidemics in recent years mirrors the evolutionary trend of the virus. Comparisons between isolates from different outbreaks have revealed an accumulation of genetic mutations and genomic reassortments that have diversified RVF virus genomes over several decades. The threat to humans posed by the diversified RVF virus strains increases the potential public health and socioeconomic impacts of future outbreaks. Understanding the shifting RVF epidemiology as determined by its evolution is key to developing new strategies for outbreak mitigation and prevention of future human RVF casualties.
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Affiliation(s)
- Marycelin Baba
- International Centre of Insect Physiology and Ecology (ICIPE), Nairobi 00100, Kenya.,Department of Medical Laboratory Science, PMB 1069, University of Maiduguri, Maiduguri 600230, Nigeria
| | - Daniel K Masiga
- International Centre of Insect Physiology and Ecology (ICIPE), Nairobi 00100, Kenya
| | - Rosemary Sang
- International Centre of Insect Physiology and Ecology (ICIPE), Nairobi 00100, Kenya
| | - Jandouwe Villinger
- International Centre of Insect Physiology and Ecology (ICIPE), Nairobi 00100, Kenya
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Abdallah MMM, Adam IA, Abdalla TM, Abdelaziz SA, Ahmed ME, Aradaib IE. A survey of rift valley fever and associated risk factors among the one-humped camel (Camelus dromedaries) in Sudan. Ir Vet J 2016; 69:6. [PMID: 27293548 PMCID: PMC4901444 DOI: 10.1186/s13620-016-0065-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 06/03/2016] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Rift valley fever (RVF) is a mosquito-borne viral disease of domestic livestock and wild ruminants. In camels RVF may cause abortion among pregnant camels, but is most often asymptomatic among other camels. In this study, a seroepidemiological survey was conducted to determine the prevalence of RVFV antibodies and to identify the potential risk factors associated with RVFV seropositivity among the Sudanese one-humped camel (Camelus dromedaries) in Khartoum State, Sudan. A cross sectional study was conducted in Khartoum State, Sudan, in a total of 240 camels selected randomly from four localities. Sera sampled were tested for the presence of RVFV-specific immunoglobulin G (IgG) antibodies using a competitive enzyme-linked immunosorbent assay (c-ELISA). RESULTS RVFV seropositivity was recorded in 23 out of 240 animals, prevalence rate of 9.6 % among camels in Khartoum State. Age (OR = 8.29, p-value = 0.04) and heavy rainfall (OR = 5.36, p value = 0.01) were recorded as potential risk factors for contracting RVF. CONCLUSIONS Older age and heavy rainfall were considered as potential risk factors for seropositivity to RVF. Surveillance for RVF among camels and distribution of mosquito vectors should continue to better understand the clinical signs associated with RVFV infection in camels and provide public health authorities an opportunity to anticipate and prepare for a possible RVF outbreak in Khartoum State, Sudan.
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Affiliation(s)
- Maiy M M Abdallah
- Molecular Biology Laboratory (MBL), Department of Clinical Medicine, Faculty of Veterinary Medicine, University of Khartoum, P.O. Box 32, Khartoum North, Sudan
| | - Ibrahim A Adam
- Molecular Biology Laboratory (MBL), Department of Clinical Medicine, Faculty of Veterinary Medicine, University of Khartoum, P.O. Box 32, Khartoum North, Sudan
| | - Tamadur M Abdalla
- Molecular Biology Laboratory (MBL), Department of Clinical Medicine, Faculty of Veterinary Medicine, University of Khartoum, P.O. Box 32, Khartoum North, Sudan
| | - Sanaa A Abdelaziz
- Molecular Biology Laboratory (MBL), Department of Clinical Medicine, Faculty of Veterinary Medicine, University of Khartoum, P.O. Box 32, Khartoum North, Sudan
| | - Mohamed E Ahmed
- Center for Viral Hemorrhagic Fevers, Al-Neelain Institute of Medical Research (NIMR), Al-Neelain University, Khartoum, Sudan
| | - Imadeldin E Aradaib
- Molecular Biology Laboratory (MBL), Department of Clinical Medicine, Faculty of Veterinary Medicine, University of Khartoum, P.O. Box 32, Khartoum North, Sudan
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Abstract
Rift Valley fever (RVF) is a zoonotic, mosquito-borne viral disease that affects human health and causes significant losses in the livestock industry. Recent outbreaks have led to severe human infections with high mortality rates. There are many challenges to applying effective preventive and control measures, including weak infrastructure of health facilities, lack of capacity and support systems for field logistics and communication, access to global expert organizations, and insufficient information on the epidemiological and reservoir status of the RVF virus. The health systems in East African countries are underdeveloped, with gaps in adaptability to new, more accurate and rapid techniques, and well-trained staff that affect their capacity to monitor and evaluate the disease. Surveillance and response systems are inadequate in providing accurate information in a timely manner for decision making to deal with the scope of interrupting the disease transmission by applying mass animal vaccination, and other preventive measures at the early stage of an outbreak. The historical vaccines are unsuitable for use in newborn and gestating livestock, and the recent ones require a booster and annual revaccination. Future live-attenuated RVF vaccines should possess lower safety concerns regardless of the physiologic state of the animal, and provide rapid and long-term immunity after a single dose of vaccination. In the absence of an effective vaccination program, prevention and control measures must be immediately undertaken after an alert is generated. These measures include enforcing and adapting standard protocols for animal trade and movement, extensive vector control, safe disposal of infected animals, and modification of human-animal contact behavior. Directing control efforts on farmers and workers who deal with, handle, or live close to livestock, and focusing on areas with populations at high risk of an epidemic are desirable. Consideration of prevention methods as a first-line strategy against RVF is practical owing to the absence of a human vaccine, particularly under the current high environmental risks and expanding global travel and animal trade. Universal platforms are needed to support coordinated efforts; alert and response operations; exchange of expertise; and disease detection, diagnosis, control, and prevention.
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Affiliation(s)
- Yousif E Himeidan
- Vector Control Unit, Africa Technical Research Centre, Vector Health International, Arusha, Tanzania
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Nanyingi MO, Munyua P, Kiama SG, Muchemi GM, Thumbi SM, Bitek AO, Bett B, Muriithi RM, Njenga MK. A systematic review of Rift Valley Fever epidemiology 1931-2014. Infect Ecol Epidemiol 2015; 5:28024. [PMID: 26234531 PMCID: PMC4522434 DOI: 10.3402/iee.v5.28024] [Citation(s) in RCA: 122] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Revised: 06/15/2015] [Accepted: 07/10/2015] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Rift Valley Fever (RVF) is a mosquito-borne viral zoonosis that was first isolated and characterized in 1931 in Kenya. RVF outbreaks have resulted in significant losses through human illness and deaths, high livestock abortions and deaths. This report provides an overview on epidemiology of RVF including ecology, molecular diversity spatiotemporal analysis, and predictive risk modeling. METHODOLOGY Using the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines, we systematically searched for relevant RVF publications in repositories of the World Health Organization Library and Information Networks for Knowledge (WHOLIS), U.S Centers for Disease Control and Prevention (CDC), and Food and Agricultural Organization (FAO). Detailed searches were performed in Google Scholar, SpringerLink, and PubMed databases and included conference proceedings and books published from 1931 up to 31st January 2015. RESULTS AND DISCUSSION A total of 84 studies were included in this review; majority (50%) reported on common human and animal risk factors that included consumption of animal products, contact with infected animals and residing in low altitude areas associated with favorable climatic and ecological conditions for vector emergence. A total of 14 (16%) of the publications described RVF progressive spatial and temporal distribution and the use of risk modeling for timely prediction of imminent outbreaks. Using distribution maps, we illustrated the gradual spread and geographical extent of disease; we also estimated the disease burden using aggregate human mortalities and cumulative outbreak periods for endemic regions. CONCLUSION This review outlines common risk factors for RVF infections over wider geographical areas; it also emphasizes the role of spatial models in predicting RVF enzootics. It, therefore, explains RVF epidemiological status that may be used for design of targeted surveillance and control programs in endemic countries.
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Affiliation(s)
- Mark O Nanyingi
- Department of Biomedical Sciences, Colorado State University, Fort Collins, CO, USA
- Department of Public Health, Pharmacology and Toxicology, University of Nairobi, Nairobi, Kenya
- Kenya Medical Research Institute, Nairobi, Kenya;
| | - Peninah Munyua
- Centers for Disease Control and Prevention, Nairobi, Kenya
| | - Stephen G Kiama
- Wangari Maathai Institute for Peace and Environmental Studies, University of Nairobi, Nairobi, Kenya
| | - Gerald M Muchemi
- Department of Public Health, Pharmacology and Toxicology, University of Nairobi, Nairobi, Kenya
| | - Samuel M Thumbi
- Kenya Medical Research Institute, Nairobi, Kenya
- Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA, USA
| | - Austine O Bitek
- Zoonotic Disease Unit, Nairobi, Kenya
- Directorate of Veterinary Service, Nairobi, Kenya
| | - Bernard Bett
- International Livestock Research Institute, Nairobi, Kenya
| | | | - M Kariuki Njenga
- Kenya Medical Research Institute, Nairobi, Kenya
- Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA, USA
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Sindato C, Pfeiffer DU, Karimuribo ED, Mboera LEG, Rweyemamu MM, Paweska JT. A Spatial Analysis of Rift Valley Fever Virus Seropositivity in Domestic Ruminants in Tanzania. PLoS One 2015; 10:e0131873. [PMID: 26162089 PMCID: PMC4498811 DOI: 10.1371/journal.pone.0131873] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Accepted: 06/03/2015] [Indexed: 12/04/2022] Open
Abstract
Rift Valley fever (RVF) is an acute arthropod-borne viral zoonotic disease primarily occurring in Africa. Since RVF-like disease was reported in Tanzania in 1930, outbreaks of the disease have been reported mainly from the eastern ecosystem of the Great Rift Valley. This cross-sectional study was carried out to describe the variation in RVF virus (RVFV) seropositivity in domestic ruminants between selected villages in the eastern and western Rift Valley ecosystems in Tanzania, and identify potential risk factors. Three study villages were purposively selected from each of the two Rift Valley ecosystems. Serum samples from randomly selected domestic ruminants (n = 1,435) were tested for the presence of specific immunoglobulin G (IgG) and M (IgM), using RVF enzyme-linked immunosorbent assay methods. Mixed effects logistic regression modelling was used to investigate the association between potential risk factors and RVFV seropositivity. The overall RVFV seroprevalence (n = 1,435) in domestic ruminants was 25.8% and speciesspecific seroprevalence was 29.7%, 27.7% and 22.0% in sheep (n = 148), cattle (n = 756) and goats (n = 531), respectively. The odds of seropositivity were significantly higher in animals sampled from the villages in the eastern than those in the western Rift Valley ecosystem (OR = 1.88, CI: 1.41, 2.51; p<0.001), in animals sampled from villages with soils of good than those with soils of poor water holding capacity (OR = 1.97; 95% CI: 1.58, 3.02; p< 0.001), and in animals which had been introduced than in animals born within the herd (OR = 5.08, CI: 2.74, 9.44; p< 0.001). Compared with animals aged 1–2 years, those aged 3 and 4–5 years had 3.40 (CI: 2.49, 4.64; p< 0.001) and 3.31 (CI: 2.27, 4.82, p< 0.001) times the odds of seropositivity. The findings confirm exposure to RVFV in all the study villages, but with a higher prevalence in the study villages from the eastern Rift Valley ecosystem.
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Affiliation(s)
- Calvin Sindato
- National Institute for Medical Research, Tabora, Tanzania
- Department of Veterinary Medicine and Public Health, Sokoine University of Agriculture, Morogoro, Tanzania
- Southern African Centre for Infectious Disease Surveillance, Morogoro, Tanzania
- * E-mail:
| | - Dirk U. Pfeiffer
- Veterinary Epidemiology, Economics & Public Health Group, Royal Veterinary College, London, United Kingdom
| | - Esron D. Karimuribo
- Department of Veterinary Medicine and Public Health, Sokoine University of Agriculture, Morogoro, Tanzania
- Southern African Centre for Infectious Disease Surveillance, Morogoro, Tanzania
| | | | - Mark M. Rweyemamu
- Southern African Centre for Infectious Disease Surveillance, Morogoro, Tanzania
| | - Janusz T. Paweska
- Center for Emerging and Zoonotic Diseases, National Institute for Communicable Diseases, National Health Laboratory Service, Sandringham, South Africa
- School of Pathology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
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Ibrahim AM, Adam IA, Osman BT, Aradaib IE. Epidemiological survey of Crimean Congo hemorrhagic fever virus in cattle in East Darfur State, Sudan. Ticks Tick Borne Dis 2015; 6:439-44. [DOI: 10.1016/j.ttbdis.2015.03.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Revised: 11/24/2014] [Accepted: 03/04/2015] [Indexed: 10/23/2022]
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Sow A, Faye O, Faye O, Diallo D, Sadio BD, Weaver SC, Diallo M, Sall AA. Rift Valley fever in Kedougou, southeastern Senegal, 2012. Emerg Infect Dis 2015; 20:504-6. [PMID: 24565408 PMCID: PMC3944877 DOI: 10.3201/eid2003.131174] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
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Himeidan YE, Kweka EJ, Mahgoub MM, El Rayah EA, Ouma JO. Recent outbreaks of rift valley Fever in East Africa and the middle East. Front Public Health 2014; 2:169. [PMID: 25340047 PMCID: PMC4186272 DOI: 10.3389/fpubh.2014.00169] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2014] [Accepted: 09/16/2014] [Indexed: 12/16/2022] Open
Abstract
Rift Valley fever (RVF) is an important neglected, emerging, mosquito-borne disease with severe negative impact on human and animal health. Mosquitoes in the Aedes genus have been considered as the reservoir, as well as vectors, since their transovarially infected eggs withstand desiccation and larvae hatch when in contact with water. However, different mosquito species serve as epizootic/epidemic vectors of RVF, creating a complex epidemiologic pattern in East Africa. The recent RVF outbreaks in Somalia (2006–2007), Kenya (2006–2007), Tanzania (2007), and Sudan (2007–2008) showed extension to districts, which were not involved before. These outbreaks also demonstrated the changing epidemiology of the disease from being originally associated with livestock, to a seemingly highly virulent form infecting humans and causing considerably high-fatality rates. The amount of rainfall is considered to be the main factor initiating RVF outbreaks. The interaction between rainfall and local environment, i.e., type of soil, livestock, and human determine the space-time clustering of RVF outbreaks. Contact with animals or their products was the most dominant risk factor to transfer the infection to humans. Uncontrolled movement of livestock during an outbreak is responsible for introducing RVF to new areas. For example, the virus that caused the Saudi Arabia outbreak in 2000 was found to be the same strain that caused the 1997–98 outbreaks in East Africa. A strategy that involves active surveillance with effective case management and diagnosis for humans and identifying target areas for animal vaccination, restriction on animal movements outside the affected areas, identifying breeding sites, and targeted intensive mosquito control programs has been shown to succeed in limiting the effect of RVF outbreak and curb the spread of the disease from the onset.
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Affiliation(s)
- Yousif E Himeidan
- Entomology Unit, Faculty of Agriculture and Natural Resources, University of Kassala , New Halfa , Sudan ; Africa Technical Research Centre, Vector Health International , Arusha , Tanzania
| | - Eliningaya J Kweka
- Division of Livestock and Human Diseases Vector Control, Tropical Pesticides Research Institute , Arusha , Tanzania ; Department of Medical Parasitology and Entomology, Catholic University of Health and Allied Sciences , Mwanza , Tanzania
| | - Mostafa M Mahgoub
- Blue Nile National Institute for Communicable Diseases, University of Gezira , Madani , Sudan
| | - El Amin El Rayah
- Department of Zoology, University of Khartoum , Khartoum , Sudan
| | - Johnson O Ouma
- Africa Technical Research Centre, Vector Health International , Arusha , Tanzania ; Biotechnology Research Institute, Kenya Agricultural and Livestock Research Organization , Kikuyu , Kenya
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Sow A, Faye O, Ba Y, Ba H, Diallo D, Faye O, Loucoubar C, Boushab M, Barry Y, Diallo M, Sall AA. Rift Valley fever outbreak, southern Mauritania, 2012. Emerg Infect Dis 2014; 20:296-9. [PMID: 24447334 PMCID: PMC3901467 DOI: 10.3201/eid2002.131000] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Rift Valley Fever Outbreak, Mauritania, 2012 After a period of heavy rainfall, an outbreak of Rift Valley fever occurred in southern Mauritania during September–November 2012. A total of 41 human cases were confirmed, including 13 deaths, and 12 Rift Valley fever virus strains were isolated. Moudjeria and Temchecket Departments were the most affected areas.
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Detection of rift valley Fever virus interepidemic activity in some hotspot areas of kenya by sentinel animal surveillance, 2009-2012. Vet Med Int 2014; 2014:379010. [PMID: 25202470 PMCID: PMC4147350 DOI: 10.1155/2014/379010] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Revised: 07/20/2014] [Accepted: 07/21/2014] [Indexed: 11/17/2022] Open
Abstract
Rift Valley fever virus causes an important zoonotic disease of humans and small ruminants in Eastern Africa and is spread primarily by a mosquito vector. In this region, it occurs as epizootics that typically occur at 5–15-year intervals associated with unusual rainfall events. It has hitherto been known that the virus is maintained between outbreaks in dormant eggs of the mosquito vector and this has formed the basis of understanding of the epidemiology and control strategies of the disease. We show here that seroconversion and sporadic acute disease do occur during the interepidemic periods (IEPs) in the absence of reported cases in livestock or humans. The finding indicates that previously undetected low-level virus transmission during the IEPs does occur and that epizootics may also be due to periodic expansion of mosquito vectors in the presence of both circulating virus and naïve animals.
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Kortekaas J. One Health approach to Rift Valley fever vaccine development. Antiviral Res 2014; 106:24-32. [DOI: 10.1016/j.antiviral.2014.03.008] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Revised: 03/10/2014] [Accepted: 03/15/2014] [Indexed: 10/25/2022]
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Hassan OA, Ahlm C, Evander M. A need for One Health approach - lessons learned from outbreaks of Rift Valley fever in Saudi Arabia and Sudan. Infect Ecol Epidemiol 2014; 4:20710. [PMID: 24505511 PMCID: PMC3915885 DOI: 10.3402/iee.v4.20710] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Revised: 09/30/2013] [Accepted: 12/20/2013] [Indexed: 11/14/2022] Open
Abstract
Introduction Rift Valley fever (RVF) is an emerging viral zoonosis that impacts human and animal health. It is transmitted from animals to humans directly through exposure to blood, body fluids, or tissues of infected animals or via mosquito bites. The disease is endemic to Africa but has recently spread to Saudi Arabia and Yemen. Our aim was to compare two major outbreaks of RVF in Saudi Arabia (2000) and Sudan (2007) from a One Health perspective. Methods Using the terms ‘Saudi Arabia’, ‘Sudan’, and ‘RVF’, articles were identified by searching PubMed, Google Scholar, and web pages of international organizations as well as local sources in Saudi Arabia and Sudan. Results The outbreak in Saudi Arabia caused 883 human cases, with a case fatality rate of 14% and more than 40,000 dead sheep and goats. In Sudan, 698 human cases of RVF were recognized (case fatality, 31.5%), but no records of affected animals were available. The ecology and environment of the affected areas were similar with irrigation canals and excessive rains providing an attractive habitat for mosquito vectors to multiply. The outbreaks resulted in livestock trade bans leading to a vast economic impact on the animal market in the two countries. The surveillance system in Sudan showed a lack of data management and communication between the regional and federal health authorities, while in Saudi Arabia which is the stronger economy, better capacity and contingency plans resulted in efficient countermeasures. Studies of the epidemiology and vectors were also performed in Saudi Arabia, while in Sudan these issues were only partly studied. Conclusion We conclude that a One Health approach is the best option to mitigate outbreaks of RVF. Collaboration between veterinary, health, and environmental authorities both on national and regional levels is needed.
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Affiliation(s)
- Osama Ahmed Hassan
- Department of Epidemiology and Diseases Control, Public Health Institute, Federal Ministry of Health, Khartoum, Sudan ; Department of Clinical Microbiology, Infectious Diseases, Umeå University, Umeå, Sweden ; Department of Clinical Microbiology, Virology, Umeå University, Umeå, Sweden
| | - Clas Ahlm
- Department of Clinical Microbiology, Infectious Diseases, Umeå University, Umeå, Sweden
| | - Magnus Evander
- Department of Clinical Microbiology, Virology, Umeå University, Umeå, Sweden
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Mweya CN, Kimera SI, Kija JB, Mboera LEG. Predicting distribution of Aedes aegypti and Culex pipiens complex, potential vectors of Rift Valley fever virus in relation to disease epidemics in East Africa. Infect Ecol Epidemiol 2013; 3:21748. [PMID: 24137533 PMCID: PMC3797365 DOI: 10.3402/iee.v3i0.21748] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2013] [Revised: 09/08/2013] [Accepted: 09/12/2013] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND The East African region has experienced several Rift Valley fever (RVF) outbreaks since the 1930s. The objective of this study was to identify distributions of potential disease vectors in relation to disease epidemics. Understanding disease vector potential distributions is a major concern for disease transmission dynamics. METHODS DIVERSE ECOLOGICAL NICHE MODELLING TECHNIQUES HAVE BEEN DEVELOPED FOR THIS PURPOSE: we present a maximum entropy (Maxent) approach for estimating distributions of potential RVF vectors in un-sampled areas in East Africa. We modelled the distribution of two species of mosquitoes (Aedes aegypti and Culex pipiens complex) responsible for potential maintenance and amplification of the virus, respectively. Predicted distributions of environmentally suitable areas in East Africa were based on the presence-only occurrence data derived from our entomological study in Ngorongoro District in northern Tanzania. RESULTS Our model predicted potential suitable areas with high success rates of 90.9% for A. aegypti and 91.6% for C. pipiens complex. Model performance was statistically significantly better than random for both species. Most suitable sites for the two vectors were predicted in central and northwestern Tanzania with previous disease epidemics. Other important risk areas include western Lake Victoria, northern parts of Lake Malawi, and the Rift Valley region of Kenya. CONCLUSION Findings from this study show distributions of vectors had biological and epidemiological significance in relation to disease outbreak hotspots, and hence provide guidance for the selection of sampling areas for RVF vectors during inter-epidemic periods.
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Affiliation(s)
- Clement Nyamunura Mweya
- National Institute for Medical Research, Tukuyu Research Centre, Tukuyu, Tanzania
- Department of Veterinary Medicine and Public Health, Sokoine University of Agriculture, Morogoro, Tanzania
| | - Sharadhuli Iddi Kimera
- Department of Veterinary Medicine and Public Health, Sokoine University of Agriculture, Morogoro, Tanzania
| | - John Bukombe Kija
- Serengeti Biodiversity Programme, Tanzania Wildlife Research Institute, Arusha, Tanzania
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