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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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2
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Kainga H, Phonera MC, Chatanga E, Kallu SA, Mpundu P, Samutela M, Chambaro HM, Kajihara M, Shempela DM, Sikalima J, Muleya W, Shawa M, Chulu J, Njunga G, Simuunza M, Takada A, Sawa H, Simulundu E, Saasa N. Seroprevalence and Associated Risk Factors of Rift Valley Fever in Livestock from Three Ecological Zones of Malawi. Pathogens 2022; 11:1349. [PMID: 36422600 PMCID: PMC9698272 DOI: 10.3390/pathogens11111349] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 11/04/2022] [Accepted: 11/10/2022] [Indexed: 09/17/2023] Open
Abstract
The epidemiology of Rift Valley fever (RVF) is poorly understood in Malawi. Here, a cross-sectional study was conducted (March-June 2020) to investigate the seroprevalence and potential risk factors of RVF virus (RVFV) in cattle, goats, and sheep in three ecological zones of Malawi. A total of 1523 serum samples were tested for anti-RVFV IgG and IgM antibodies by ELISA. Additionally, a questionnaire survey was used to assess potential RVF risk factors. The overall seroprevalence was 17.14% (261/1523; 95% CI = 15.33-19.11) for individual livestock and 33.24% (120/361; 95% CI = 28.18-38.11) for the livestock herd. Seroprevalence was significantly high in sheep (25.68%, 95% CI = 19.31-33.26) compared with cattle (21.35%, 95% CI = 18.74-24.22) and goats (7.72%, 95% CI = 5.72-10.34), (p = 0.047). At the individual livestock level, the risk was elevated in female livestock (OR: 1.74, 95% CI = 1.08-12.82) (p = 0.016), while at the herd level, areas receiving approximately 1001-1500 mm of rainfall (OR: 2.47, 95% CI = 1.14-5.37) (p = 0.022), areas of rainfall amount greater than approximately 1600 mm (OR: 2.239, 95% CI = 1.07-8.82) (p = 0.023), and mixed species herds (OR: 10.410, 95% CI = 3.04-35.59) (p = 0.001), were significant risk factors. The detection of IgM antibodies confirmed active circulation of RVFV in Malawi. Therefore, monitoring of RVF in animals, humans, and vectors using a "One Health" approach, along with community sensitization among the high-risk populations, could help mitigate the threat posed by this zoonotic disease in Malawi.
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Affiliation(s)
- Henson Kainga
- Department of Veterinary Epidemiology and Public Health, Faculty of Veterinary Medicine, Lilongwe University of Agriculture and Natural Resources, Lilongwe 207203, Malawi
- Department of Disease Control, School of Veterinary Medicine, University of Zambia, Lusaka 10101, Zambia
| | - Marvin Collen Phonera
- Department of Animal Health and Livestock Development, Ministry of Agriculture, Lilongwe 207203, Malawi
| | - Elisha Chatanga
- Department of Veterinary Pathobiology, Faculty of Veterinary Medicine, Lilongwe University of Agriculture and Natural Resources, Lilongwe 207203, Malawi
| | - Simegnew Adugna Kallu
- Department of Disease Control, School of Veterinary Medicine, University of Zambia, Lusaka 10101, Zambia
- College of Veterinary Medicine, Haramaya University, Dire Dawa P.O. Box 138, Ethiopia
| | - Prudence Mpundu
- Department of Environmental and Occupational Health, Levy Mwanawasa Medical University, Lusaka 33991, Zambia
| | - Mulemba Samutela
- Department of Paraclinical Studies, School of Veterinary Medicine, University of Zambia, Lusaka 10101, Zambia
- Department of Biomedical Sciences, School of Health Sciences, University of Zambia, Lusaka 10101, Zambia
| | - Herman Moses Chambaro
- Virology Unit, Central Veterinary Research Institute (CVRI), Ministry of Fisheries and Livestock, Lusaka 10101, Zambia
| | - Masahiro Kajihara
- Department of Disease Control, School of Veterinary Medicine, University of Zambia, Lusaka 10101, Zambia
- Division of Global Epidemiology, International Institute for Zoonosis Control, Hokkaido University, Sapporo 001-0020, Japan
| | | | - Jay Sikalima
- Churches Health Association of Zambia, Lusaka 10101, Zambia
| | - Walter Muleya
- Department of Biomedical Sciences, School of Veterinary Medicine, University of Zambia, Lusaka 10101, Zambia
| | - Misheck Shawa
- Division of Collaboration and Education, International Institute for Zoonosis Control, Hokkaido University, Sapporo 001-0020, Japan
| | - Julius Chulu
- Department of Animal Health and Livestock Development, Ministry of Agriculture, Lilongwe 207203, Malawi
| | - Gilson Njunga
- Department of Animal Health and Livestock Development, Ministry of Agriculture, Lilongwe 207203, Malawi
| | - Martin Simuunza
- Department of Disease Control, School of Veterinary Medicine, University of Zambia, Lusaka 10101, Zambia
| | - Ayato Takada
- Department of Disease Control, School of Veterinary Medicine, University of Zambia, Lusaka 10101, Zambia
- Division of Collaboration and Education, International Institute for Zoonosis Control, Hokkaido University, Sapporo 001-0020, Japan
| | - Hirofumi Sawa
- Department of Disease Control, School of Veterinary Medicine, University of Zambia, Lusaka 10101, Zambia
- Department of Biomedical Sciences, School of Veterinary Medicine, University of Zambia, Lusaka 10101, Zambia
- Japan Division of International Research Promotion, International Institute for Zoonosis Control, Hokkaido University, Sapporo 001-0020, Japan
- Japan Global Virus Network, Baltimore, ML 21201, USA
- One Health Research Center, Hokkaido University, Sapporo 001-0020, Japan
| | - Edgar Simulundu
- Department of Disease Control, School of Veterinary Medicine, University of Zambia, Lusaka 10101, Zambia
- Macha Research Trust, Choma 20100, Zambia
| | - Ngonda Saasa
- Department of Disease Control, School of Veterinary Medicine, University of Zambia, Lusaka 10101, Zambia
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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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Kainga H, Mponela J, Basikolo L, Phonera MC, Mpundu P, Munyeme M, Simulundu E, Saasa N. Assessment of Knowledge, Attitudes, and Practices towards Rift Valley Fever among Livestock Farmers in Selected Districts of Malawi. Trop Med Infect Dis 2022; 7:tropicalmed7080167. [PMID: 36006259 PMCID: PMC9415226 DOI: 10.3390/tropicalmed7080167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Revised: 08/01/2022] [Accepted: 08/02/2022] [Indexed: 11/16/2022] Open
Abstract
Rift Valley fever (RVF) is a mosquito-borne viral zoonosis whose cases go unreported in endemic areas without active surveillance. Information on the knowledge, attitude, and practice of RVF among livestock farmers remains speculative in Malawi. A cross-section survey using a semi-structured questionnaire (n = 400) was conducted in eight districts of Malawi to capture information on knowledge, attitude, and management practices (KAP) regarding RVF. The average KAP score was calculated from total scores for knowledge, attitude, and practices and then assessed. The association between the level of knowledge and factors of knowledge, factors of attitude, and factors of practices was determined using Pearson chi-square. Multivariate analysis was used to determine the predictors of knowledge. Participants had an overall poor knowledge (score = 17.94%), negative attitude (score = 9.40%), and poor management practices (score = 41.23%) towards RVF. Only 8.25% (33/400) of participants had sufficient knowledge of RVF. The study found that the cause of abortion (OR: 3.86 (95% CI: 1.14–13.05)) (p = 0.030) and knowledge on transmission of RVFV (OR: 5.65 (95% CI: 1.76–18.12)) (p = 0.004) were predictors of insufficient knowledge of RVF. The current study reported that participants had insufficient knowledge and a negative attitude despite displaying limited management practices towards RVF. Therefore, this study recommends community sensitization to RVF and advocates for the importance of reporting suspected cases to relevant authorities for proper management.
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Affiliation(s)
- Henson Kainga
- Department of Veterinary Epidemiology and Public Health, Faculty of Veterinary Medicine, Lilongwe University of Agriculture and Natural Resources, Lilongwe 207203, Malawi
- Department of Disease Control, School of Veterinary Medicine, University of Zambia, Lusaka 10101, Zambia
- Correspondence: or
| | - James Mponela
- Department of Animal Health and Livestock Development, Ministry of Agriculture, Lilongwe 207203, Malawi
| | - Linda Basikolo
- Department of Animal Health and Livestock Development, Ministry of Agriculture, Lilongwe 207203, Malawi
| | - Marvin Collen Phonera
- Department of Animal Health and Livestock Development, Ministry of Agriculture, Lilongwe 207203, Malawi
| | - Prudence Mpundu
- Department of Environmental and Occupational Health, Levy Mwanawasa Medical University, Lusaka 33991, Zambia
| | - Muso Munyeme
- Department of Disease Control, School of Veterinary Medicine, University of Zambia, Lusaka 10101, Zambia
| | - Edgar Simulundu
- Department of Disease Control, School of Veterinary Medicine, University of Zambia, Lusaka 10101, Zambia
- Macha Research Trust, Choma 20100, Zambia
| | - Ngonda Saasa
- Department of Disease Control, School of Veterinary Medicine, University of Zambia, Lusaka 10101, Zambia
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5
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Bronsvoort BM, Kelly RF, Freeman E, Callaby R, Bagninbom JM, Ndip L, Handel IG, Tanya VN, Morgan KL, Ngwa VN, Rossi G, Nfon CK, Mazeri S. A Cross-Sectional, Population-Based, Seroepidemiological Study of Rift Valley Fever in Cameroonian Cattle Populations. Front Vet Sci 2022; 9:897481. [PMID: 35774979 PMCID: PMC9237551 DOI: 10.3389/fvets.2022.897481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Accepted: 05/02/2022] [Indexed: 11/13/2022] Open
Abstract
Rift Valley fever (RVF) is an important emerging zoonoses causing abortion and neonatal deaths in livestock and hemorrhagic fever in humans. It is typically characterized by acute epidemics with abortion storms often preceding human disease and these events have been associated with the El Niño weather cycles. Outside of areas that experience epidemics, little is known about its epidemiology. Here, we present results from a serological study using biobank samples from a study of cattle conducted in 2013 at two sites in Cameroon. A total of 1,458 cattle from 100 herds were bled and sera screened using a commercially available RVF ELISA. The overall design-adjusted animal-level apparent seroprevalence of RVF exposure for the Northwest Region (NWR) of Cameroon was 6.5% (95% CI: 3.9–11.0) and for the Vina Division (VIN) of the Adamawa Region was 8.2% (95% CI: 6.2–11.0). The age-stratified serological results were also used to estimate the force of infection, and the age-independent estimates were 0.029 for the VIN and 0.024 for the NWR. The effective reproductive number was ~1.08. Increasing age and contact with wild antelope species were associated with an increased risk of seropositivity, while high altitudes and contact with buffalo were associated with a reduced risk of seropositivity. The serological patterns are more consistent with an endemical stability rather than the more typical epidemic patterns seen in East Africa. However, there is little surveillance in livestock for abortion storms or in humans with fevers in Cameroon, and it is, therefore, difficult to interpret these observations. There is an urgent need for an integrated One Health approach to understand the levels of human- and livestock-related clinical and asymptomatic disease and whether there is a need to implement interventions such as vaccination.
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Affiliation(s)
- Barend Mark Bronsvoort
- Epidemiology, Economics and Risk Assessment (EERA) Group, The Roslin Institute, The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, United Kingdom
- Farm Animal Services, The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, United Kingdom
- *Correspondence: Barend Mark Bronsvoort
| | - Robert Francis Kelly
- Epidemiology, Economics and Risk Assessment (EERA) Group, The Roslin Institute, The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, United Kingdom
- Farm Animal Services, The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, United Kingdom
| | - Emily Freeman
- Farm Animal Services, The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, United Kingdom
| | - Rebecca Callaby
- Epidemiology, Economics and Risk Assessment (EERA) Group, The Roslin Institute, The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, United Kingdom
| | - Jean Marc Bagninbom
- School of Veterinary Medicine and Sciences, University of Ngaoundere, Ngaoundere, Cameroon
| | - Lucy Ndip
- Laboratory of Emerging Infectious Diseases, University of Buea, Buea, Cameroon
| | - Ian Graham Handel
- Epidemiology, Economics and Risk Assessment (EERA) Group, The Roslin Institute, The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, United Kingdom
- Farm Animal Services, The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, United Kingdom
| | | | - Kenton Lloyd Morgan
- Institute of Ageing and Chronic Disease and School of Veterinary Science, University of Liverpool, Liverpool, United Kingdom
| | - Victor Ngu Ngwa
- School of Veterinary Medicine and Sciences, University of Ngaoundere, Ngaoundere, Cameroon
| | - Gianluigi Rossi
- Epidemiology, Economics and Risk Assessment (EERA) Group, The Roslin Institute, The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, United Kingdom
| | - Charles K. Nfon
- National Centre for Foreign Animal Disease, Winnipeg, MB, Canada
| | - Stella Mazeri
- Epidemiology, Economics and Risk Assessment (EERA) Group, The Roslin Institute, The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Edinburgh, United Kingdom
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6
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Eckstein S, Ehmann R, Gritli A, Ben Rhaiem M, Ben Yahia H, Diehl M, Wölfel R, Handrick S, Ben Moussa M, Stoecker K. Viral and Bacterial Zoonotic Agents in Dromedary Camels from Southern Tunisia: A Seroprevalence Study. Microorganisms 2022; 10:microorganisms10040727. [PMID: 35456778 PMCID: PMC9028256 DOI: 10.3390/microorganisms10040727] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 03/17/2022] [Accepted: 03/28/2022] [Indexed: 12/10/2022] Open
Abstract
The rapid spread of SARS-CoV-2 clearly demonstrated the potential of zoonotic diseases to cause severe harm to public health. Having limited access to medical care combined with severe underreporting and a lack of active surveillance, Africa carries a high burden of neglected zoonotic diseases. Therefore, the epidemiological monitoring of pathogen circulation is essential. Recently, we found extensive Middle East respiratory syndrome coronavirus (MERS-CoV) prevalence in free-roaming dromedary camels from southern Tunisia. In this study, we aimed to investigate the seroprevalence, and thus the risk posed to public health, of two additional viral and two bacterial pathogens in Tunisian dromedaries: Rift Valley fever virus (RVFV), foot-and-mouth disease virus (FMDV), Coxiella burnetii and Brucella spp. via ELISA. With 73.6% seropositivity, most animals had previously been exposed to the causative agent of Q fever, C. burnetii. Additionally, 7.4% and 1.0% of the dromedaries had antibodies against Brucella and RVFV, respectively, while no evidence was found for the occurrence of FMDV. Our studies revealed considerable immunological evidence of various pathogens within Tunisian dromedary camels. Since these animals have intense contact with humans, they pose a high risk of transmitting serious zoonotic diseases during active infection. The identification of appropriate countermeasures is therefore highly desirable.
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Affiliation(s)
- Simone Eckstein
- Bundeswehr Institute of Microbiology (IMB), 80937 Munich, Germany; (R.E.); (M.D.); (R.W.); (S.H.); (K.S.)
- Correspondence: ; Tel.: +49-992692-3990
| | - Rosina Ehmann
- Bundeswehr Institute of Microbiology (IMB), 80937 Munich, Germany; (R.E.); (M.D.); (R.W.); (S.H.); (K.S.)
| | - Abderraouf Gritli
- Veterinary Service, General Directorate of Military Health, Ministry of National Defense, Tunis 1000, Tunisia; (A.G.); (M.B.R.); (H.B.Y.)
| | - Mohamed Ben Rhaiem
- Veterinary Service, General Directorate of Military Health, Ministry of National Defense, Tunis 1000, Tunisia; (A.G.); (M.B.R.); (H.B.Y.)
| | - Houcine Ben Yahia
- Veterinary Service, General Directorate of Military Health, Ministry of National Defense, Tunis 1000, Tunisia; (A.G.); (M.B.R.); (H.B.Y.)
| | - Manuel Diehl
- Bundeswehr Institute of Microbiology (IMB), 80937 Munich, Germany; (R.E.); (M.D.); (R.W.); (S.H.); (K.S.)
| | - Roman Wölfel
- Bundeswehr Institute of Microbiology (IMB), 80937 Munich, Germany; (R.E.); (M.D.); (R.W.); (S.H.); (K.S.)
| | - Susann Handrick
- Bundeswehr Institute of Microbiology (IMB), 80937 Munich, Germany; (R.E.); (M.D.); (R.W.); (S.H.); (K.S.)
| | - Mohamed Ben Moussa
- Department of Virology, Military Hospital of Instruction of Tunis, Tunis 1008, Tunisia;
| | - Kilian Stoecker
- Bundeswehr Institute of Microbiology (IMB), 80937 Munich, Germany; (R.E.); (M.D.); (R.W.); (S.H.); (K.S.)
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7
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Anyamba A, Damoah R, Kemp A, Small JL, Rostal MK, Bagge W, Cordel C, Brand R, Karesh WB, Paweska JT. Climate Conditions During a Rift Valley Fever Post-epizootic Period in Free State, South Africa, 2014–2019. Front Vet Sci 2022; 8:730424. [PMID: 35187137 PMCID: PMC8848741 DOI: 10.3389/fvets.2021.730424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2021] [Accepted: 12/20/2021] [Indexed: 11/13/2022] Open
Abstract
Rift Valley fever virus (RVFV) activity in Southern Africa tends to occur during periods of sustained elevated rainfall, cooler than normal conditions, and abundant vegetation cover creating ideal conditions for the increase and propagation of populations of RVFV mosquito vectors. These climatic and ecological conditions are modulated by large-scale tropical-wide El Niño–Southern Oscillation (ENSO) phenomena. The aim of this 5-year study was to investigate climatic conditions during Rift Valley fever “post-epizootic” period in Free State province of the Republic of South Africa, which historically experienced the largest RVF outbreaks in this country. We collected satellite-derived rainfall, land surface temperature (LST), and normalized difference vegetation index (NDVI) data since 2014 to understand broad environmental conditions in the years following a period of sustained and widespread large RVF outbreaks (2008–2011) in the region. We found this post-epizootic/interepizootic period to be characterized by below-normal rainfall (~-500 mm), above LSTs (~+12°C), depressed NDVI (60% below normal), and severe drought as manifested particularly during the 2015–2016 growing season. Such conditions reduce the patchwork of appropriate habitats available for emergence of RVFV vectors and diminish chances of RVFV activity. However, the 2016–2017 growing season saw a marked return to somewhat wetter conditions without any reported RVFV transmission. In general, the aggregate vector collections during this 5-year period follow patterns observed in climate measurements. During the 2017–2018 growing season, late and seasonally above average rainfall resulted in a focal RVF outbreak in one location in the study region. This unanticipated event is an indicator of cryptic RVF activity during post-epizootic period and may be a harbinger of RVFV activity in the coming years.
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Affiliation(s)
- Assaf Anyamba
- Universities Space Research Association, Columbia, MD, United States
- Biospheric Sciences Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD, United States
- *Correspondence: Assaf Anyamba
| | - Richard Damoah
- Biospheric Sciences Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD, United States
- Physics Department and Goddard Earth Sciences Technology and Research, Morgan State University, Baltimore, MD, United States
| | - Alan Kemp
- Center for Emerging and Zoonotic Diseases, Johannesburg, South Africa
| | - Jennifer L. Small
- Biospheric Sciences Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD, United States
- Science Systems and Applications, Inc., Lanham, MD, United States
| | | | | | | | - Robert Brand
- Cuyahoga County Board of Health, Parma, OH, United States
- Department of Soil, Crop and Climate Sciences, University of the Free State, Bloemfontein, South Africa
| | | | - Janusz T. Paweska
- Center for Emerging and Zoonotic Diseases, Johannesburg, South Africa
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8
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Gerken KN, LaBeaud AD, Mandi H, L’Azou Jackson M, Breugelmans JG, King CH. Paving the way for human vaccination against Rift Valley fever virus: A systematic literature review of RVFV epidemiology from 1999 to 2021. PLoS Negl Trop Dis 2022; 16:e0009852. [PMID: 35073355 PMCID: PMC8812886 DOI: 10.1371/journal.pntd.0009852] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2021] [Revised: 02/03/2022] [Accepted: 12/22/2021] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Rift Valley fever virus (RVFV) is a lethal threat to humans and livestock in many parts of Africa, the Arabian Peninsula, and the Indian Ocean. This systematic review's objective was to consolidate understanding of RVFV epidemiology during 1999-2021 and highlight knowledge gaps relevant to plans for human vaccine trials. METHODOLOGY/PRINCIPAL FINDINGS The review is registered with PROSPERO (CRD42020221622). Reports of RVFV infection or exposure among humans, animals, and/or vectors in Africa, the Arabian Peninsula, and the Indian Ocean during the period January 1999 to June 2021 were eligible for inclusion. Online databases were searched for publications, and supplemental materials were recovered from official reports and research colleagues. Exposures were classified into five groups: 1) acute human RVF cases, 2) acute animal cases, 3) human RVFV sero-surveys, 4) animal sero-surveys, and 5) arthropod infections. Human risk factors, circulating RVFV lineages, and surveillance methods were also tabulated. In meta-analysis of risks, summary odds ratios were computed using random-effects modeling. 1104 unique human or animal RVFV transmission events were reported in 39 countries during 1999-2021. Outbreaks among humans or animals occurred at rates of 5.8/year and 12.4/year, respectively, with Mauritania, Madagascar, Kenya, South Africa, and Sudan having the most human outbreak years. Men had greater odds of RVFV infection than women, and animal contact, butchering, milking, and handling aborted material were significantly associated with greater odds of exposure. Animal infection risk was linked to location, proximity to water, and exposure to other herds or wildlife. RVFV was detected in a variety of mosquito vectors during interepidemic periods, confirming ongoing transmission. CONCLUSIONS/SIGNIFICANCE With broad variability in surveillance, case finding, survey design, and RVFV case confirmation, combined with uncertainty about populations-at-risk, there were inconsistent results from location to location. However, it was evident that RVFV transmission is expanding its range and frequency. Gaps assessment indicated the need to harmonize human and animal surveillance and improve diagnostics and genotyping. Given the frequency of RVFV outbreaks, human vaccination has strong potential to mitigate the impact of this now widely endemic disease.
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Affiliation(s)
- Keli N. Gerken
- Division of Pediatric Infectious Diseases, Department of Pediatrics, Stanford University School of Medicine, Stanford, California, United States of America
| | - A. Desirée LaBeaud
- Division of Pediatric Infectious Diseases, Department of Pediatrics, Stanford University School of Medicine, Stanford, California, United States of America
| | - Henshaw Mandi
- Coalition for Epidemic Preparedness Innovations (CEPI), Oslo, Norway
| | | | | | - Charles H. King
- Center for Global Health and Diseases, Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, Ohio, United States of America
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Smith LJ, Schurer JM, Ntakiyisumba E, Shyaka A, Amuguni JH. Rift Valley fever knowledge, mitigation strategies and communication preferences among male and female livestock farmers in Eastern Province, Rwanda. PLoS Negl Trop Dis 2021; 15:e0009705. [PMID: 34424895 PMCID: PMC8412303 DOI: 10.1371/journal.pntd.0009705] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Revised: 09/02/2021] [Accepted: 08/04/2021] [Indexed: 01/04/2023] Open
Abstract
The Government of Rwanda reported an outbreak of Rift Valley fever (RVF) in the Eastern Province in 2018. To respond to the outbreak, vaccination and education campaigns about the disease were carried out. Because RVF cases continue to be detected in Rwanda and the disease impacts livelihoods and health, accurate knowledge and communication are imperative. The objectives of this study were to evaluate knowledge and risk perceptions of RVF transmission among livestock farmers in Nyagatare District, Eastern Province, Rwanda, and to compare RVF knowledge, risk perceptions, and farming practices between male and female livestock farmers. This cross-sectional, quantitative study was conducted in selected sectors of Nyagatare District in the Eastern Province of Rwanda in June 2019. A 34-question survey was used to ask about demographics, livestock ownership, risk perceptions about zoonotic diseases and livestock management, RVF knowledge, preferred communication sources and information sharing strategies, and protective strategies for RVF mitigation while working with livestock. Livestock farmers were interviewed at three milk collection centers, two village meeting points, a farm cooperative meeting, and during door-to-door visits in villages. In total, 123 livestock farmers were interviewed. The survey found that most livestock farmers lacked knowledge about epizootic and zoonotic transmission of RVF, more male livestock farmers were familiar with RVF and risk mitigation strategies, and female livestock farmers are not viewed as reliable sources of information. Additionally, most livestock farmers had not vaccinated their animals against RVF despite past vaccination campaigns. Radio was the most popular communication channel. These findings show that RVF knowledge and information sharing are inadequate among livestock farmers in Eastern Province. Therefore, vaccination and education campaigns may need to be reevaluated within the context of these trends in order to prepare for future RVF outbreaks. This study was conducted in order to evaluate RVF knowledge and awareness as well as communication and mitigation strategies among livestock farmers in Eastern Province, Rwanda. Rwanda declared an outbreak of RVF in 2018 and cases have continued to be detected. Thus, evaluating the status of knowledge, preventive strategies, and information sharing among livestock farmers is crucial in mitigating future outbreaks. Our team conducted a survey of knowledge, risk perceptions, mitigation strategies, and communication practices among livestock farmers from selected sectors within Nyagatare District and compared them between male and female livestock farmers in order to analyze gender-nuanced differences between these groups. Sectors were chosen for sampling based on their proximity to previous outbreak areas. Survey questionnaire results showed that knowledge and risk perceptions differed between male and female livestock farmers, and that they could be generally improved among all livestock farmers. Female livestock farmers and non-farming community members were viewed as unreliable sources of information which could impact information dissemination. Many farmers also reported that their livestock herds were not vaccinated for the disease despite previous vaccination campaigns. Communication strategies and information sources also differed between male and female livestock farmers, which highlights a need to consider gender in improving RVF vaccination and education campaign coverage. These findings pose implications for future community-based public health interventions as well as policy development for RVF control and mitigating future RVF outbreaks within Rwanda.
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Affiliation(s)
- Lindsay J. Smith
- Department of Infectious Disease and Global Health, Cummings School of Veterinary Medicine at Tufts University, North Grafton, Massachusetts, United States of America
- * E-mail:
| | - Janna M. Schurer
- Department of Infectious Disease and Global Health, Cummings School of Veterinary Medicine at Tufts University, North Grafton, Massachusetts, United States of America
- Center for One Health, University of Global Health Equity, Kigali, Rwanda
| | - Eurade Ntakiyisumba
- School of Veterinary Medicine, College of Agriculture, Animal Sciences and Veterinary Medicine, University of Rwanda, Nyagatare, Rwanda
| | - Anselme Shyaka
- School of Veterinary Medicine, College of Agriculture, Animal Sciences and Veterinary Medicine, University of Rwanda, Nyagatare, Rwanda
| | - Janetrix Hellen Amuguni
- Department of Infectious Disease and Global Health, Cummings School of Veterinary Medicine at Tufts University, North Grafton, Massachusetts, United States of America
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First Serological Evidence of Crimean-Congo Hemorrhagic Fever Virus and Rift Valley Fever Virus in Ruminants in Tunisia. Pathogens 2021; 10:pathogens10060769. [PMID: 34207423 PMCID: PMC8234966 DOI: 10.3390/pathogens10060769] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Revised: 05/24/2021] [Accepted: 06/09/2021] [Indexed: 11/16/2022] Open
Abstract
Crimean-Congo hemorrhagic fever virus (CCHFV, Nairoviridae family) and Rift Valley fever virus (RVFV, Phenuiviridae family) are zoonotic vector-borne pathogens with clinical relevance worldwide. Our study aimed to determine seroprevalences of these viruses and potential risk factors among livestock (cattle, sheep, and goats) in Tunisia. Sera were tested for antibodies against CCHFV (n = 879) and RVFV (n = 699) using various enzyme-linked immunosorbent assays (ELISAs) and indirect immunofluorescence assays (IIFA). The overall seroprevalence of IgG antibodies was 8.6% (76/879) and 2.3% (16/699) against CCHFV and RVFV, respectively. For CCHF seropositivity bioclimatic zones and breed were potential risk factors for the three tested animal species; while the season was associated with cattle and sheep seropositivity, tick infestation was associated with cattle and goats seropositivity and age as a risk factor was only associated with cattle seropositivity. Age and season were significantly associated with RVFV seropositivity in sheep. Our results confirm the circulation of CCHFV and RVFV in Tunisia and identified the principal risk factors in ruminants. This knowledge could help to mitigate the risk of ruminant infections and subsequently also human infections.
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11
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Sanderson CE, Jori F, Moolla N, Paweska JT, Oumer N, Alexander KA. Silent Circulation of Rift Valley Fever in Humans, Botswana, 2013-2014. Emerg Infect Dis 2021; 26:2453-2456. [PMID: 32946735 PMCID: PMC7510741 DOI: 10.3201/eid2610.191837] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
We evaluated the prevalence of Rift Valley fever virus IgG and IgM in human serum samples (n = 1,276) collected in 2013–2014 in northern Botswana. Our findings provide evidence of active circulation of this virus in humans in the absence of clinical disease in this region.
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12
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Safini N, Bamouh Z, Hamdi J, Jazouli M, Tadlaoui KO, El Harrak M. In-vitro and in-vivo study of the interference between Rift Valley fever virus (clone 13) and Sheeppox/Limpy Skin disease viruses. Sci Rep 2021; 11:12395. [PMID: 34117312 PMCID: PMC8196192 DOI: 10.1038/s41598-021-91926-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 05/17/2021] [Indexed: 11/09/2022] Open
Abstract
Viral interference is a common occurrence that has been reported in cell culture in many cases. In the present study, viral interference between two capripox viruses (sheeppox SPPV and lumpy skin disease virus LSDV in cattle) with Rift Valley fever virus (RVFV) was investigated in vitro and in their natural hosts, sheep and cattle. A combination of SPPV/RVFV and LSDV/RVFV was used to co-infect susceptible cells and animals to detect potential competition. In-vitro interference was evaluated by estimating viral infectivity and copies of viral RNA by a qPCR during three serial passages in cell cultures, whereas in-vivo interference was assessed through antibody responses to vaccination. When lamb testis primary cells were infected with the mixture of capripox and RVFV, the replication of both SPPV and LSDV was inhibited by RVFV. In animals, SPPV/RVFV or LSDV/RVFV combinations inhibited the replication SPPV and LSDV and the antibody response following vaccination. The combined SPPV/RVFV did not protect sheep after challenging with the virulent strain of SPPV and the LSDV/RVFV did not induce interferon Gamma to LSDV, while immunological response to RVFV remain unaffected. Our goal was to assess this interference response to RVFV/capripoxviruses’ coinfection in order to develop effective combined live-attenuated vaccines as a control strategy for RVF and SPP/LSD diseases. Our findings indicated that this approach was not suitable for developing a combined SPPV/LSDV/RVFV vaccine candidate because of interference of replication and the immune response among these viruses.
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Affiliation(s)
- N Safini
- R&D Virology, MCI Santé Animale, Lot. 157, Z I, Sud-Ouest (ERAC), B.P. 278, 28810, Mohammedia, Morocco.
| | - Z Bamouh
- R&D Virology, MCI Santé Animale, Lot. 157, Z I, Sud-Ouest (ERAC), B.P. 278, 28810, Mohammedia, Morocco
| | - J Hamdi
- R&D Virology, MCI Santé Animale, Lot. 157, Z I, Sud-Ouest (ERAC), B.P. 278, 28810, Mohammedia, Morocco
| | - M Jazouli
- R&D Virology, MCI Santé Animale, Lot. 157, Z I, Sud-Ouest (ERAC), B.P. 278, 28810, Mohammedia, Morocco
| | - K O Tadlaoui
- R&D Virology, MCI Santé Animale, Lot. 157, Z I, Sud-Ouest (ERAC), B.P. 278, 28810, Mohammedia, Morocco
| | - M El Harrak
- R&D Virology, MCI Santé Animale, Lot. 157, Z I, Sud-Ouest (ERAC), B.P. 278, 28810, Mohammedia, Morocco
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13
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Msimang V, Weyer J, le Roux C, Kemp A, Burt FJ, Tempia S, Grobbelaar A, Moolla N, Rostal MK, Bagge W, Cordel C, Karesh WB, Paweska JT, Thompson PN. Risk factors associated with exposure to Crimean-Congo haemorrhagic fever virus in animal workers and cattle, and molecular detection in ticks, South Africa. PLoS Negl Trop Dis 2021; 15:e0009384. [PMID: 34048430 PMCID: PMC8162673 DOI: 10.1371/journal.pntd.0009384] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 04/12/2021] [Indexed: 11/19/2022] Open
Abstract
Crimean-Congo haemorrhagic fever (CCHF) is a severe tick-borne viral zoonosis endemic to parts of Africa, Europe, the Middle East and Central Asia. Human cases are reported annually in South Africa, with a 25% case fatality rate since the first case was recognized in 1981. We investigated CCHF virus (CCHFV) seroprevalence and risk factors associated with infection in cattle and humans, and the presence of CCHFV in Hyalomma spp. ticks in central South Africa in 2017-18. CCHFV IgG seroprevalence was 74.2% (95%CI: 64.2-82.1%) in 700 cattle and 3.9% (95%CI: 2.6-5.8%) in 541 farm and wildlife workers. No veterinary personnel (117) or abattoir workers (382) were seropositive. The prevalence of CCHFV RNA was significantly higher in Hyalomma truncatum (1.6%) than in H. rufipes (0.2%) (P = 0.002). Seroprevalence in cattle increased with age and was greater in animals on which ticks were found. Seroprevalence in cattle also showed significant geographic variation. Seroprevalence in humans increased with age and was greater in workers who handled livestock for injection and collection of samples. Our findings support previous evidence of widespread high CCHFV seroprevalence in cattle and show significant occupational exposure amongst farm and wildlife workers. Our seroprevalence estimate suggests that CCHFV infections are five times more frequent than the 215 confirmed CCHF cases diagnosed in South Africa in the last four decades (1981-2019). With many cases undiagnosed, the potential seriousness of CCHF in people, and the lack of an effective vaccine or treatment, there is a need to improve public health awareness, prevention and disease control.
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Affiliation(s)
- Veerle Msimang
- Epidemiology Section, Department of Production Animal Studies, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa
- Centre for Emerging Zoonotic and Parasitic Diseases, National Institute for Communicable Diseases of the National Health Laboratory Service, Sandringham, South Africa
- * E-mail:
| | - Jacqueline Weyer
- Centre for Emerging Zoonotic and Parasitic Diseases, National Institute for Communicable Diseases of the National Health Laboratory Service, Sandringham, South Africa
- Centre for Viral Zoonoses, University of Pretoria, Pretoria, South Africa
| | - Chantel le Roux
- Centre for Emerging Zoonotic and Parasitic Diseases, National Institute for Communicable Diseases of the National Health Laboratory Service, Sandringham, South Africa
| | - Alan Kemp
- Centre for Emerging Zoonotic and Parasitic Diseases, National Institute for Communicable Diseases of the National Health Laboratory Service, Sandringham, South Africa
| | - Felicity J. Burt
- Division of Virology, National Health Laboratory Service, Bloemfontein, South Africa
- Faculty of Health Sciences, University of the Free State, Bloemfontein, South Africa
| | - Stefano Tempia
- School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | - Antoinette Grobbelaar
- Centre for Emerging Zoonotic and Parasitic Diseases, National Institute for Communicable Diseases of the National Health Laboratory Service, Sandringham, South Africa
| | - Naazneen Moolla
- Centre for Emerging Zoonotic and Parasitic Diseases, National Institute for Communicable Diseases of the National Health Laboratory Service, Sandringham, South Africa
| | | | - Whitney Bagge
- EcoHealth Alliance, New York, New York, United States of America
| | | | | | - Janusz T. Paweska
- Centre for Emerging Zoonotic and Parasitic Diseases, National Institute for Communicable Diseases of the National Health Laboratory Service, Sandringham, South Africa
- Centre for Viral Zoonoses, University of Pretoria, Pretoria, South Africa
| | - Peter N. Thompson
- Epidemiology Section, Department of Production Animal Studies, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa
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14
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Outammassine A, Zouhair S, Loqman S. Rift Valley Fever and West Nile virus vectors in Morocco: Current situation and future anticipated scenarios. Transbound Emerg Dis 2021; 69:1466-1478. [PMID: 33876581 DOI: 10.1111/tbed.14113] [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: 12/04/2020] [Revised: 04/07/2021] [Accepted: 04/14/2021] [Indexed: 11/29/2022]
Abstract
Rift Valley Fever (RVF) and West Nile virus (WNV) are two important emerging Arboviruses transmitted by Aedes and Culex mosquitoes, typically Ae. caspius, Ae. detritus and Cx. pipiens in temperate regions. In Morocco, several outbreaks of WNV (1996, 2003 and 2010), affecting horses mostly, have been reported in north-western regions resulting in the death of 55 horses and one person cumulatively. Serological evidence of WNV local circulation, performed one year after the latest outbreak, revealed WNV neutralizing bodies in 59 out of 499 tested participants (El Rhaffouli et al., 2012). The country also shares common borders with northern Mauritania, where RVF is often documented. Human movement, livestock trade, climate changes and the availability of susceptible mosquito vectors are expected to increase the spread of these diseases in the country. Thus, in this study, we gathered a data set summarizing occurrences of Ae. caspius, Ae. detritus and Cx. pipiens in the country, and generated model prediction for their potential distribution under both current and future (2050) climate conditions, as a proxy to identify regions at-risk of RVF and WNV probable expansion. We found that the north-western regions (where the population is most concentrated), specifically along the Atlantic coastline, are highly suitable for Ae. caspius, Ae. detritus and Cx. pipiens, under present-day conditions. Future model scenarios anticipated possible range changes for the three mosquitoes under all climatic assumptions. All of the studied species are prospected to gain new areas that are currently not suitable, even under the most optimist scenario, thus placing additional human populations at risk. Our maps and predictions offer an opportunity to strategically target surveillance and control programmes. Public health officials, entomological surveillance and control delegation must augment efforts and continuously monitor these areas to reduce and minimize human infection risk.
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Affiliation(s)
- Abdelkrim Outammassine
- Laboratoire de Lutte contre les Maladies Infectieuses, Faculty of Medicine and Pharmacy, Cadi Ayyad University, Marrakech, Morocco
| | - Said Zouhair
- Laboratoire de Lutte contre les Maladies Infectieuses, Faculty of Medicine and Pharmacy, Cadi Ayyad University, Marrakech, Morocco.,Laboratory of Bacteriology-Virology, Avicienne Hospital Military, Marrakech, Morocco
| | - Souad Loqman
- Laboratoire de Lutte contre les Maladies Infectieuses, Faculty of Medicine and Pharmacy, Cadi Ayyad University, Marrakech, Morocco
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15
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Gilbride C, Saunders J, Sharpe H, Maze EA, Limon G, Ludi AB, Lambe T, Belij-Rammerstorfer S. The Integration of Human and Veterinary Studies for Better Understanding and Management of Crimean-Congo Haemorrhagic Fever. Front Immunol 2021; 12:629636. [PMID: 33815379 PMCID: PMC8012513 DOI: 10.3389/fimmu.2021.629636] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Accepted: 03/01/2021] [Indexed: 12/15/2022] Open
Abstract
Outbreaks that occur as a result of zoonotic spillover from an animal reservoir continue to highlight the importance of studying the disease interface between species. One Health approaches recognise the interdependence of human and animal health and the environmental interplay. Improving the understanding and prevention of zoonotic diseases may be achieved through greater consideration of these relationships, potentially leading to better health outcomes across species. In this review, special emphasis is given on the emerging and outbreak pathogen Crimean-Congo Haemorrhagic Fever virus (CCHFV) that can cause severe disease in humans. We discuss the efforts undertaken to better understand CCHF and the importance of integrating veterinary and human research for this pathogen. Furthermore, we consider the use of closely related nairoviruses to model human disease caused by CCHFV. We discuss intervention approaches with potential application for managing CCHFV spread, and how this concept may benefit both animal and human health.
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Affiliation(s)
- Ciaran Gilbride
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Jack Saunders
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Hannah Sharpe
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | | | | | | | - Teresa Lambe
- The Jenner Institute, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
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16
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Rostal MK, Cleaveland S, Cordel C, van Staden L, Matthews L, Anyamba A, Karesh WB, Paweska JT, Haydon DT, Ross N. Farm-Level Risk Factors of Increased Abortion and Mortality in Domestic Ruminants during the 2010 Rift Valley Fever Outbreak in Central South Africa. Pathogens 2020; 9:E914. [PMID: 33158214 PMCID: PMC7694248 DOI: 10.3390/pathogens9110914] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 10/25/2020] [Accepted: 10/30/2020] [Indexed: 11/28/2022] Open
Abstract
(1) Background: Rift Valley fever (RVF) outbreaks in domestic ruminants have severe socio-economic impacts. Climate-based continental predictions providing early warnings to regions at risk for RVF outbreaks are not of a high enough resolution for ruminant owners to assess their individual risk. (2) Methods: We analyzed risk factors for RVF occurrence and severity at the farm level using the number of domestic ruminant deaths and abortions reported by farmers in central South Africa during the 2010 RVF outbreaks using a Bayesian multinomial hurdle framework. (3) Results: We found strong support that the proportion of days with precipitation, the number of water sources, and the proportion of goats in the herd were positively associated with increased severity of RVF (the numbers of deaths and abortions). We did not find an association between any risk factors and whether RVF was reported on farms. (4) Conclusions: At the farm level we identified risk factors of RVF severity; however, there was little support for risk factors of RVF occurrence. The identification of farm-level risk factors for Rift Valley fever virus (RVFV) occurrence would support and potentially improve current prediction methods and would provide animal owners with critical information needed in order to assess their herd's risk of RVFV infection.
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Affiliation(s)
- Melinda K. Rostal
- EcoHealth Alliance, New York, NY 10018, USA; (W.B.K.); (N.R.)
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK; (S.C.); (L.M.); (D.T.H.)
| | - Sarah Cleaveland
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK; (S.C.); (L.M.); (D.T.H.)
| | - Claudia Cordel
- ExecuVet PTY LTD., Bloemfontein 9301, Free State, South Africa; (C.C.); (L.v.S.)
| | - Lara van Staden
- ExecuVet PTY LTD., Bloemfontein 9301, Free State, South Africa; (C.C.); (L.v.S.)
| | - Louise Matthews
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK; (S.C.); (L.M.); (D.T.H.)
| | - Assaf Anyamba
- Universities Space Research Association, Columbia, MD 21046, USA;
- NASA Goddard Space Flight Center, Biospheric Sciences Laboratory, Greenbelt, MD 20771, USA
| | | | - Janusz T. Paweska
- Centre for Emerging Zoonotic and Parasitic Diseases, National Institute for Communicable Diseases, National Health Laboratory Service, Johannesburg 2192, South Africa;
| | - Daniel T. Haydon
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK; (S.C.); (L.M.); (D.T.H.)
| | - Noam Ross
- EcoHealth Alliance, New York, NY 10018, USA; (W.B.K.); (N.R.)
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Odendaal L, Clift SJ, Fosgate GT, Davis AS. Ovine Fetal and Placental Lesions and Cellular Tropism in Natural Rift Valley Fever Virus Infections. Vet Pathol 2020; 57:791-806. [PMID: 32885745 DOI: 10.1177/0300985820954549] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Infection with Rift Valley fever phlebovirus (RVFV) causes abortion storms and a wide variety of outcomes for both ewes and fetuses. Sheep fetuses and placenta specimens were examined during the 2010-2011 River Valley fever (RVF) outbreak in South Africa. A total of 72 fetuses were studied of which 58 were confirmed positive for RVF. Placenta specimens were available for 35 cases. Macroscopic lesions in fetuses were nonspecific and included marked edema and occasional hemorrhages in visceral organs. Microscopically, multifocal hepatic necrosis was present in 48 of 58 cases, and apoptotic bodies, foci of liquefactive hepatic necrosis (primary foci), and eosinophilic intranuclear inclusions in hepatocytes were useful diagnostic features. Lymphocytolysis was present in all lymphoid organs examined with the exception of thymus and Peyer's patches, and pyknosis or karyorrhexis was often present in renal glomeruli. The most significant histologic lesion in the placenta was necrosis of trophoblasts and endothelial cells in the cotyledonary and intercotyledonary chorioallantois. Immunolabeling for RVFV was most consistent in trophoblasts of the cotyledon or caruncle. Other antigen-positive cells included hepatocytes, renal tubular epithelial, juxtaglomerular and extraglomerular mesangial cells, vascular smooth muscle, endothelial and adrenocortical cells, cardiomyocytes, Purkinje fibers, and macrophages. Fetal organ samples for diagnosis must minimally include liver, kidney, and spleen. From the placenta, the minimum recommended specimens for histopathology include the cotyledonary units and caruncles from the endometrium, if available. The diagnostic investigation of abortion in endemic areas should always include routine testing for RVFV, and a diagnosis during interepidemic periods might be missed if only limited specimens are available for examination.
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Affiliation(s)
- Lieza Odendaal
- 56410University of Pretoria, Onderstepoort, Pretoria, South Africa
| | - Sarah J Clift
- 56410University of Pretoria, Onderstepoort, Pretoria, South Africa
| | | | - A Sally Davis
- 56410University of Pretoria, Onderstepoort, Pretoria, South Africa.,5308Kansas State University, Manhattan, KS, USA
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