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Rakau KG, Nyaga MM, Gededzha MP, Mwenda JM, Mphahlele MJ, Seheri LM, Steele AD. Genetic characterization of G12P[6] and G12P[8] rotavirus strains collected in six African countries between 2010 and 2014. BMC Infect Dis 2021; 21:107. [PMID: 33482744 PMCID: PMC7821174 DOI: 10.1186/s12879-020-05745-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 12/27/2020] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND G12 rotaviruses were first observed in sub-Saharan Africa in 2004 and since then have continued to emerge and spread across the continent and are reported as a significant human rotavirus genotype in several African countries, both prior to and after rotavirus vaccine introduction. This study investigated the genetic variability of 15 G12 rotavirus strains associated with either P[6] or P[8] identified between 2010 and 2014 from Ethiopia, Kenya, Rwanda, Tanzania, Togo and Zambia. METHODS The investigation was carried out by comparing partial VP7 and partial VP4 sequences of the African G12P[6] and G12P[8] strains with the available GenBank sequences and exploring the recognized neutralization epitopes of these strains. Additionally, Bayesian evolutionary analysis was carried out using Markov Chain Monte Carlo (MCMC) implemented in BEAST to estimate the time to the most recent ancestor and evolutionary rate for these G12 rotavirus strains. RESULTS The findings suggested that the VP7 and VP4 nucleotide and amino acid sequences of the G12 strains circulating in African countries are closely related, irrespective of country of origin and year of detection, with the exception of the Ethiopian strains that clustered distinctly. Neutralization epitope analysis revealed that rotavirus VP4 P[8] genes associated with G12 had amino acid sequences similar to those reported globally including the vaccine strains in RotaTeq and Rotarix. The estimated evolutionary rate of the G12 strains was 1.016 × 10- 3 substitutions/site/year and was comparable to what has been previously reported. Three sub-clusters formed within the current circulating lineage III shows the diversification of G12 from three independent ancestries within a similar time frame in the late 1990s. CONCLUSIONS At present it appears to be unlikely that widespread vaccine use has driven the molecular evolution and sustainability of G12 strains in Africa. Continuous monitoring of rotavirus genotypes is recommended to assess the long-term impact of rotavirus vaccination on the dynamic nature of rotavirus evolution on the continent.
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Affiliation(s)
- Kebareng G Rakau
- Diarrhoeal Pathogens Research Unit, Department of Virology, WHO AFRO Rotavirus Regional Reference Laboratory, Sefako Makgatho Health Sciences University, Pretoria, South Africa
| | - Martin M Nyaga
- Diarrhoeal Pathogens Research Unit, Department of Virology, WHO AFRO Rotavirus Regional Reference Laboratory, Sefako Makgatho Health Sciences University, Pretoria, South Africa.,Next Generation Sequencing Unit and Department of Medical Microbiology and Virology, Faculty of Health Sciences, University of the Free State, Bloemfontein, South Africa
| | - Maemu P Gededzha
- Diarrhoeal Pathogens Research Unit, Department of Virology, WHO AFRO Rotavirus Regional Reference Laboratory, Sefako Makgatho Health Sciences University, Pretoria, South Africa.,National Health Laboratory Service, Department of Molecular Medicine and Haematology, Charlotte Maxeke Johannesburg Academic Hospital, Johannesburg, South Africa
| | - Jason M Mwenda
- African Rotavirus Surveillance Network, Immunization, Vaccines and Development Cluster, WHO African Regional Office, Brazzaville, Congo
| | - M Jeffrey Mphahlele
- Diarrhoeal Pathogens Research Unit, Department of Virology, WHO AFRO Rotavirus Regional Reference Laboratory, Sefako Makgatho Health Sciences University, Pretoria, South Africa.,South African Medical Research Council, Soutpansberg Road, Pretoria, South Africa
| | - L Mapaseka Seheri
- Diarrhoeal Pathogens Research Unit, Department of Virology, WHO AFRO Rotavirus Regional Reference Laboratory, Sefako Makgatho Health Sciences University, Pretoria, South Africa
| | - A Duncan Steele
- Diarrhoeal Pathogens Research Unit, Department of Virology, WHO AFRO Rotavirus Regional Reference Laboratory, Sefako Makgatho Health Sciences University, Pretoria, South Africa. .,Present address: Enteric and Diarrheal Diseases, Global Health, Bill & Melinda Gates Foundation, Seattle, WA, USA.
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2
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Mokoena F, Esona MD, Seheri LM, Nyaga MM, Magagula NB, Mukaratirwa A, Mulindwa A, Abebe A, Boula A, Tsolenyanu E, Simwaka J, Rakau KG, Peenze I, Mwenda JM, Mphahlele MJ, Steele AD. Whole Genome Analysis of African G12P[6] and G12P[8] Rotaviruses Provides Evidence of Porcine-Human Reassortment at NSP2, NSP3, and NSP4. Front Microbiol 2021; 11:604444. [PMID: 33510725 PMCID: PMC7835662 DOI: 10.3389/fmicb.2020.604444] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2020] [Accepted: 12/10/2020] [Indexed: 01/27/2023] Open
Abstract
Group A rotaviruses (RVA) represent the most common cause of pediatric gastroenteritis in children <5 years, worldwide. There has been an increase in global detection and reported cases of acute gastroenteritis caused by RVA genotype G12 strains, particularly in Africa. This study sought to characterize the genomic relationship between African G12 strains and determine the possible origin of these strains. Whole genome sequencing of 34 RVA G12P[6] and G12P[8] strains detected from the continent including southern (South Africa, Zambia, Zimbabwe), eastern (Ethiopia, Uganda), central (Cameroon), and western (Togo) African regions, were sequenced using the Ion Torrent PGM method. The majority of the strains possessed a Wa-like backbone with consensus genotype constellation of G12-P[6]/P[8]-I1-R1-C1-M1-A1-N1-T1-E1-H1, while a single strain from Ethiopia displayed a DS-1-like genetic constellation of G12-P[6]-I2-R2-C2-M2-A2-N2-T2-E2-H2. In addition, three Ethiopian and one South African strains exhibited a genotype 2 reassortment of the NSP3 gene, with genetic constellation of G12-P[8]-I1-R1-C1-M1-A1-N1-T2-E1-H1. Overall, 10 gene segments (VP1–VP4, VP6, and NSP1–NSP5) of African G12 strains were determined to be genetically related to cognate gene sequences from globally circulating human Wa-like G12, G9, and G1 strains with nucleotide (amino acid) identities in the range of 94.1–99.9% (96.5–100%), 88.5–98.5% (93–99.1%), and 89.8–99.0% (88.7–100%), respectively. Phylogenetic analysis showed that the Ethiopian G12P[6] possessing a DS-1-like backbone consistently clustered with G2P[4] strains from Senegal and G3P[6] from Ethiopia with the VP1, VP2, VP6, and NSP1–NSP4 genes. Notably, the NSP2, NSP3, and NSP4 of most of the study strains exhibited the closest relationship with porcine strains suggesting the occurrence of reassortment between human and porcine strains. Our results add to the understanding of potential roles that interspecies transmission play in generating human rotavirus diversity through reassortment events and provide insights into the evolutionary dynamics of G12 strains spreading across selected sub-Saharan Africa regions.
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Affiliation(s)
- Fortunate Mokoena
- Department of Biochemistry, Faculty of Natural and Agricultural Science, North West University, Mmabatho, South Africa.,Diarrhoeal Pathogens Research Unit, Department of Virology, Sefako Makgatho Health Sciences University, Pretoria, South Africa
| | - Mathew Dioh Esona
- Diarrhoeal Pathogens Research Unit, Department of Virology, Sefako Makgatho Health Sciences University, Pretoria, South Africa
| | - Luyanda Mapaseka Seheri
- Diarrhoeal Pathogens Research Unit, Department of Virology, Sefako Makgatho Health Sciences University, Pretoria, South Africa
| | - Martin Munene Nyaga
- Next Generation Sequencing Unit and Division of Virology, Faculty of Health Sciences, University of the Free State, Bloemfontein, South Africa
| | - Nonkululelo Bonakele Magagula
- Diarrhoeal Pathogens Research Unit, Department of Virology, Sefako Makgatho Health Sciences University, Pretoria, South Africa
| | - Arnold Mukaratirwa
- Department of Medical Microbiology, University of Zimbabwe-College of Health Sciences, Harare, Zimbabwe
| | | | - Almaz Abebe
- Ethiopian Public Health Institute, Addis Ababa, Ethiopia
| | - Angeline Boula
- Mother and Child Center, Chantal Biya Foundation, Yaoundé, Cameroon
| | - Enyonam Tsolenyanu
- Department of Paediatrics, Sylvanus Olympio Teaching Hospital of Lome, Lome, Togo
| | - Julia Simwaka
- Virology Laboratory, University Teaching Hospital, Lusaka, Zambia
| | - Kebareng Giliking Rakau
- Diarrhoeal Pathogens Research Unit, Department of Virology, Sefako Makgatho Health Sciences University, Pretoria, South Africa
| | - Ina Peenze
- Diarrhoeal Pathogens Research Unit, Department of Virology, Sefako Makgatho Health Sciences University, Pretoria, South Africa
| | - Jason Mathiu Mwenda
- African Rotavirus Surveillance Network, Immunization, Vaccines and Development Cluster, WHO African Regional Office, Brazzaville, Congo
| | - Maphahlaganye Jeffrey Mphahlele
- Diarrhoeal Pathogens Research Unit, Department of Virology, Sefako Makgatho Health Sciences University, Pretoria, South Africa
| | - Andrew Duncan Steele
- Diarrhoeal Pathogens Research Unit, Department of Virology, Sefako Makgatho Health Sciences University, Pretoria, South Africa.,Enteric and Diarrheal Diseases, Global Health, Bill & Melinda Gates Foundation, Seattle, WA, United States
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Japhet MO, Famurewa O, Iturriza-Gomara M, Adesina OA, Opaleye OO, Niendorf S, Bock CT, Mas Marques A. Group A rotaviruses circulating prior to a national immunization programme in Nigeria: Clinical manifestations, high G12P[8] frequency, intra-genotypic divergence of VP4 and VP7. J Med Virol 2018; 90:239-249. [PMID: 28906005 DOI: 10.1002/jmv.24949] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Accepted: 09/06/2017] [Indexed: 12/24/2022]
Abstract
Nigeria having approximately 50 000 Rotavirus A (RVA) deaths annually is yet to introduce RVA vaccine into routine national immunization; therefore surveillance of RVA strains circulating before vaccine introduction is essential in evaluating impact of the intervention. Stool samples and sociodemographic data of diarrhoeic children, <5 years were collected between August 2012 and December 2013. While a high prevalence of RVA infection (47.6%; 49/103) was observed by quantitative reverse transcription real time PCR, only 25% (26/103) had high RVA genome concentrations and were antigen positive. G and P types were obtained for 31 and 37 samples respectively. G12P[8] strains were predominant (30.6%; 16/31); Other genotypes found included G9, G3, G2 and P[4], P[6], P[8]. A G12 + G2/P[8] + P[6] mixed infection was detected. The P[8] genotype showed divergence with strains distributed in lineage III and IV. Compared to the vaccines, changes in antigenic sites of VP8* and VP7 were found. The finding of the G2P[6] genotype combination and emergence of G12 strains support observations in most of the recent RVA studies from Africa. P[6] is common in many African countries, in contrast to countries in Europe and the Americas. In conclusion, this study shows the circulation of other RVA genotypes compared to the common RVA genotypes in Nigeria. PCR results should be interpreted with caution to avoid significant bias from samples with low RVA genome concentrations. These findings provide important information on the detection and molecular epidemiology of RVA prior to vaccination and contribute as a baseline for future evaluations after possible vaccine introduction.
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Affiliation(s)
- Margaret O Japhet
- Department of Microbiology, Faculty of Science, Obafemi Awolowo University, Ile-Ife, Osun State, Nigeria
- Department of Microbiology, Faculty of Science, Ekiti State University, Ado-Ekiti, Ekiti State, Nigeria
- Department of Viral Gastroenteritis and Hepatitis Pathogens and Enteroviruses, Robert Koch-Institute, Berlin, Germany
| | - Oladiran Famurewa
- Department of Microbiology, Faculty of Science, Ekiti State University, Ado-Ekiti, Ekiti State, Nigeria
- Department of Biological Sciences, Microbiology Unit, Kings University, Ode-omu, Osun State
| | | | - Olufisayo A Adesina
- Department of Microbiology, Faculty of Science, Obafemi Awolowo University, Ile-Ife, Osun State, Nigeria
| | - Oluyinka O Opaleye
- Department of Medical Microbiology and Parasitology, Ladoke Akintola University, Osogbo, Osun state, Nigeria
| | - Sandra Niendorf
- Department of Viral Gastroenteritis and Hepatitis Pathogens and Enteroviruses, Robert Koch-Institute, Berlin, Germany
| | - C Thomas Bock
- Department of Viral Gastroenteritis and Hepatitis Pathogens and Enteroviruses, Robert Koch-Institute, Berlin, Germany
| | - Andreas Mas Marques
- Department of Viral Gastroenteritis and Hepatitis Pathogens and Enteroviruses, Robert Koch-Institute, Berlin, Germany
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Moussa A, Fredj MBH, BenHamida-Rebaï M, Fodha I, Boujaafar N, Trabelsi A. Phylogenetic analysis of partial VP7 gene of the emerging human group A rotavirus G12 strains circulating in Tunisia. J Med Microbiol 2017; 66:112-118. [DOI: 10.1099/jmm.0.000420] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Affiliation(s)
- Amal Moussa
- Faculty of Pharmacy, University of Monastir, 5000 Monastir, Tunisia
- LR14SP02, Epidemiology and Immunogenetics of Human Viral Infections, Laboratory of Microbiology, Sahloul University Hospital, 4054 Sousse, Tunisia
| | - Mouna Ben Hadj Fredj
- Faculty of Sciences and Techniques, University of Kairouan, 9100 Kairouan, Tunisia
- LR14SP02, Epidemiology and Immunogenetics of Human Viral Infections, Laboratory of Microbiology, Sahloul University Hospital, 4054 Sousse, Tunisia
| | - Meriam BenHamida-Rebaï
- Faculty of Pharmacy, University of Monastir, 5000 Monastir, Tunisia
- LR14SP02, Epidemiology and Immunogenetics of Human Viral Infections, Laboratory of Microbiology, Sahloul University Hospital, 4054 Sousse, Tunisia
| | - Imene Fodha
- Faculty of Pharmacy, University of Monastir, 5000 Monastir, Tunisia
- LR14SP02, Epidemiology and Immunogenetics of Human Viral Infections, Laboratory of Microbiology, Sahloul University Hospital, 4054 Sousse, Tunisia
| | - Noureddine Boujaafar
- Laboratory of Microbiology, Sahloul University Hospital, 4054 Sousse, Tunisia
- Faculty of Pharmacy, University of Monastir, 5000 Monastir, Tunisia
| | - Abdelhalim Trabelsi
- Faculty of Pharmacy, University of Monastir, 5000 Monastir, Tunisia
- LR14SP02, Epidemiology and Immunogenetics of Human Viral Infections, Laboratory of Microbiology, Sahloul University Hospital, 4054 Sousse, Tunisia
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Agutu MT, Ongus J, Kombich J, Kamenwa R, Nyangao J, Kagira J, Ogutu AA, Bitek A. Prevalence and genetic diversity of rotavirus infection in children with acute gastroenteritis in a hospital setting, Nairobi Kenya in post vaccination era: a cross-sectional study. Pan Afr Med J 2017; 26:38. [PMID: 28451016 PMCID: PMC5398238 DOI: 10.11604/pamj.2017.26.38.10312] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2016] [Accepted: 12/19/2016] [Indexed: 12/02/2022] Open
Abstract
Introduction Rotavirus is the leading cause of severe diarrhoea among infants and young children. Each year more than 611 000 children die from rotavirus gastroenteritis, and two million are hospitalized, worldwide. In Kenya, the impact of recent rotavirus vaccinations on morbidities has not been estimated. The study aimed at determining the prevalence and identity of rotavirus strains isolated from rotavirus-associated diarrhoea in vaccinated children presenting with acute gastroenteritis. Methods Two hundred and ninety eight specimen from children presented at Gertrude Childrens’ Hospital from January to June 2012 were tested by EIA (Enzyme-linked Immunosorbent Assay) for rotavirus antigens. Molecular characterization was conducted on rotavirus-positive specimens. Extracted viral RNA was separated by polyacrylamide gel electrophoresis (PAGE) and the specific rotavirus VP4 (P-types) and VP7 (G-types) determined. Results The prevalence rate of rotavirus was 31.5% (94/298). Of the rotavirus dsRNA, 57 (60.1%) gave visible RNA profiles, 38 (40.4%) assigned long electropherotypes while 19 (20.2%) were short electropherotypes. The strains among the vaccinated were G3P [4], G12P [6], G3P [6], G9P [4], G mixed G9/3P [4] and G1/3P [4]. Specifically, the G genotypes were G9/3 (5.3%), G9 (4.3%), G3 (4.3%), G12 (2.1%) and mixed G1/3 (1.1%). The P genotypes detected were P [4] (5.3%) and P [6] (5.3%). Conclusion The present study demonstrates diversity in circulating genotypes with emergence of genotypes G3, G9, G12 and mixed genotypes G9/3 and recommends that vaccines should be formulated with a broad range of strains to include G9 and G12.
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Affiliation(s)
- Mary-Theresa Agutu
- Institute of Tropical Medicine and Infectious Diseases, Kenya.,Jomo Kenyatta University of Agriculture and Technology, Kenya
| | - Julliette Ongus
- Jomo Kenyatta University of Agriculture and Technology, Kenya
| | | | | | | | - John Kagira
- Jomo Kenyatta University of Agriculture and Technology, Kenya
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Wandera EA, Mohammad S, Komoto S, Maeno Y, Nyangao J, Ide T, Kathiiko C, Odoyo E, Tsuji T, Taniguchi K, Ichinose Y. Molecular epidemiology of rotavirus gastroenteritis in Central Kenya before vaccine introduction, 2009-2014. J Med Virol 2016; 89:809-817. [DOI: 10.1002/jmv.24691] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/16/2016] [Indexed: 11/07/2022]
Affiliation(s)
- Ernest A. Wandera
- Institute of Tropical Medicine, Center for Microbiology Research, KEMRI; KEMRI-Nagasaki University; Nairobi Kenya
| | - Shah Mohammad
- Institute of Tropical Medicine, Center for Microbiology Research, KEMRI; KEMRI-Nagasaki University; Nairobi Kenya
| | - Satoshi Komoto
- Department of Virology and Parasitology, School of Medicine; Fujita Health University; Toyoake Japan
| | - Yoshimasa Maeno
- Department of Virology and Parasitology, School of Medicine; Fujita Health University; Toyoake Japan
| | | | - Tomihiko Ide
- Department of Virology and Parasitology, School of Medicine; Fujita Health University; Toyoake Japan
| | - Cyrus Kathiiko
- Institute of Tropical Medicine, Center for Microbiology Research, KEMRI; KEMRI-Nagasaki University; Nairobi Kenya
| | - Erick Odoyo
- Institute of Tropical Medicine, Center for Microbiology Research, KEMRI; KEMRI-Nagasaki University; Nairobi Kenya
| | - Takao Tsuji
- Department of Microbiology, School of Medicine; Fujita Health University; Toyoake Japan
| | - Koki Taniguchi
- Department of Virology and Parasitology, School of Medicine; Fujita Health University; Toyoake Japan
| | - Yoshio Ichinose
- Institute of Tropical Medicine, Center for Microbiology Research, KEMRI; KEMRI-Nagasaki University; Nairobi Kenya
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Madhi SA, Cunliffe NA, Steele D, Witte D, Kirsten M, Louw C, Ngwira B, Victor JC, Gillard PH, Cheuvart BB, Han HH, Neuzil KM. Effect of human rotavirus vaccine on severe diarrhea in African infants. Malawi Med J 2016; 28:108-114. [PMID: 27895844 PMCID: PMC5117000] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023] Open
Abstract
BACKGROUND Rotavirus is the most common cause of severe gastroenteritis among young children worldwide. Data are needed to assess the efficacy of the rotavirus vaccine in African children. METHODS We conducted a randomized, placebo-controlled, multicenter trial in South Africa (3166 infants; 64.1% of the total) and Malawi (1773 infants; 35.9% of the total) to evaluate the efficacy of a live, oral rotavirus vaccine in preventing severe rotavirus gastroenteritis. Healthy infants were randomly assigned in a 1:1:1 ratio to receive two doses of vaccine (in addition to one dose of placebo) or three doses of vaccine - the pooled vaccine group - or three doses of placebo at 6, 10, and 14 weeks of age. Episodes of gastroenteritis caused by wild-type rotavirus during the first year of life were assessed through active follow-up surveillance and were graded with the use of the Vesikari scale. RESULTS A total of 4939 infants were enrolled and randomly assigned to one of the three groups; 1647 infants received two doses of the vaccine, 1651 infants received three doses of the vaccine, and 1641 received placebo. Of the 4417 infants included in the per-protocol efficacy analysis, severe rotavirus gastroenteritis occurred in 4.9% of the infants in the placebo group and in 1.9% of those in the pooled vaccine group (vaccine efficacy, 61.2%; 95% confidence interval, 44.0 to 73.2). Vaccine efficacy was lower in Malawi than in South Africa (49.4% vs. 76.9%); however, the number of episodes of severe rotavirus gastroenteritis that were prevented was greater in Malawi than in South Africa (6.7 vs. 4.2 cases prevented per 100 infants vaccinated per year). Efficacy against all-cause severe gastroenteritis was 30.2%. At least one serious adverse event was reported in 9.7% of the infants in the pooled vaccine group and in 11.5% of the infants in the placebo group. CONCLUSIONS Human rotavirus vaccine significantly reduced the incidence of severe rotavirus gastroenteritis among African infants during the first year of life. (ClinicalTrials.gov number, NCT00241644.).
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Affiliation(s)
- Shabir A Madhi
- Vaccine Preventable Diseases, University of the Witwatersrand, Johannesburg, South Africa
| | - Nigel A Cunliffe
- Division of Medical Microbiology, University of Liverpool, Liverpool, United Kingdom
| | - Duncan Steele
- Initiative for Vaccine Research, World Health Organization, Geneva
| | - Desirée Witte
- Division of Medical Microbiology, University of Liverpool, Liverpool, United Kingdom; College of Medicine, University of Malawi, Blantyre, Malawi
| | - Mari Kirsten
- Department of Paediatric Surgery, University of Pretoria, Pretoria, South Africa
| | - Cheryl Louw
- Madibeng Center for Research, Brits, South Africa; Medical Research Council Diarrhoeal Pathogens Research Unit, University of Limpopo, Limpopo, South Africa
| | - Bagrey Ngwira
- College of Medicine, University of Malawi, Blantyre, Malawi
| | - John C Victor
- Rotavirus Vaccine Program, PATH, Seattle, Washington, U.S.A
| | | | | | - Htay H Han
- GlaxoSmithKline Biologicals, Rixensart, Belgium
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da Silva MFM, Fumian TM, de Assis RMS, Fialho AM, Carvalho-Costa FA, da Silva Ribeiro de Andrade J, Leite JPG. VP7 and VP8* genetic characterization of group A rotavirus genotype G12P[8]: Emergence and spreading in the Eastern Brazilian coast in 2014. J Med Virol 2016; 89:64-70. [PMID: 27322509 DOI: 10.1002/jmv.24605] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/11/2016] [Indexed: 11/07/2022]
Abstract
Group A rotavirus (RVA) genotype G12 is habitually associated with diarrhea disease (DD) in African children and recently its detection has increased worldwide. A total of 970 stool samples collected from individuals with DD in the Northeastern, Southeastern, and Southern Brazilian regions, Eastern coast, were analyzed and 321 (33%) were positive for RVA and of these, 241 (75%) genotyped as G12P[8]. The rate of RVA positivity was higher among children aged 5-10 years old (60%). All RVA infections observed in adults aged >21 years were G12P[8] (n = 27) showing that this genotype affected older age groups during the year of 2014 in Brazil. Phylogenetic analysis of VP7 and VP8* G12P[8] strains demonstrated an elevated similarity among Brazilian and G12-III prototypes strains circulating worldwide recently, suggesting that this lineage is associated with the global spread of the G12 genotype, considered as the 6th most prevalent human RVA genotype nowadays; while other G12 lineages remain sporadically detected and usually detected in association with other P genotypes. VP8* analysis revealed that Brazilian strains belong to P[8]-3 lineage, the single P[8] lineage presently detected in the country. No major nucleotide/amino acid disparities were observed among strains recovered from children and adults for VP7 and VP8* genes. These data are essential to support the surveillance studies, particularly in countries where the RVA vaccine was introduced in their National Immunization Program enabling identification of potential alterations in the epidemiological profile that can impact its efficacy in vaccination programs. J. Med. Virol. 89:64-70, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Marcelle Figueira Marques da Silva
- Laboratory of Comparative and Environmental Virology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Ministry of Health, Rio de Janeiro, RJ, Brazil.
| | - Tulio Machado Fumian
- Laboratory of Comparative and Environmental Virology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Ministry of Health, Rio de Janeiro, RJ, Brazil
| | - Rosane Maria Santos de Assis
- Laboratory of Comparative and Environmental Virology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Ministry of Health, Rio de Janeiro, RJ, Brazil
| | - Alexandre Madi Fialho
- Laboratory of Comparative and Environmental Virology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Ministry of Health, Rio de Janeiro, RJ, Brazil
| | - Filipe Anibal Carvalho-Costa
- Laboratory of Comparative and Environmental Virology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Ministry of Health, Rio de Janeiro, RJ, Brazil
| | - Juliana da Silva Ribeiro de Andrade
- Laboratory of Comparative and Environmental Virology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Ministry of Health, Rio de Janeiro, RJ, Brazil
| | - José Paulo Gagliardi Leite
- Laboratory of Comparative and Environmental Virology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation, Ministry of Health, Rio de Janeiro, RJ, Brazil
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9
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Genetic diversity of rotavirus strains in children with diarrhea in Lagos, Nigeria. ASIAN PACIFIC JOURNAL OF TROPICAL DISEASE 2016. [DOI: 10.1016/s2222-1808(16)61080-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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10
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Moussa A, Ben Hadj Fredj M, Fodha I, BenHamida-Rebaï M, Kacem S, Argoubi A, Bennour H, Boujaafar N, Trabelsi A. Distribution of rotavirus VP7 and VP4 genotypes circulating in Tunisia from 2009 to 2014: Emergence of the genotype G12. J Med Microbiol 2016; 65:1028-1037. [PMID: 27375269 DOI: 10.1099/jmm.0.000305] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Group A rotavirus (RVA) represents the most important aetiological agent of diarrhoea in children worldwide. From January 2009 to December 2014, a multi-centre study realized through 11 Tunisian cities was undertaken among children aged <5 years consulting or hospitalized for acute gastroenteritis. A total of 1127 faecal samples were collected. All samples were screened by ELISA for the presence of RVA antigen. RVA-positive samples were further analyzed by PAGE and used for G/P-genotyping by semi-nested multiplex RT-PCR. Globally, 270 specimens (24 %) were RVA-positive, with peaks observed annually between November and March. Nine different electropherotypes could be visualized by PAGE, six with a long profile (173 cases) and two with a short one (seven cases). Mixed profiles were detected in two cases. Among the 267 VP7 genotyped strains, the predominant G- genotype was G1 (39.6 %) followed by G3 (22.2 %), G4 (13 %), G9 (11.5 %), G2 (5.2 %) and G12 (5.2 %). Among the 260 VP4 genotyped strains, P[8] genotype was the predominant (74.5 %) followed by P[6] (10.4 %) and P[4] (5.5 %). A total of 257 strains (95.2 %) could be successfully G- and P-genotyped. G1P[8] was the most prevalent combination (34.4 %), followed by G3P[8] (16.3 %), G9P[8] (10.3 %), G4P[8] (8.9 %), G2P[4] (4 %), G12P[6] (2.6 %) and G12P[8] (1.9 %). Uncommon G/Pgenotype combinations, mixed infections and untypeable strains were also detected. This is the first report, in Tunisia, of multiple detection of an emerging human RVA strain, G12 genotype. This study highlighted the need for maintaining active surveillance of emerging strains in Northern Africa.
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Affiliation(s)
- Amal Moussa
- LR14SP02, Epidemiology and Immunogenetics of Human Viral Infections, Laboratory of Microbiology, Sahloul University Hospital, 4054 Sousse, Tunisia
| | - Mouna Ben Hadj Fredj
- LR14SP02, Epidemiology and Immunogenetics of Human Viral Infections, Laboratory of Microbiology, Sahloul University Hospital, 4054 Sousse, Tunisia.,Faculty of Sciences and Techniques, University of Kairouan, Kairouan, Tunisia
| | - Imene Fodha
- LR14SP02, Epidemiology and Immunogenetics of Human Viral Infections, Laboratory of Microbiology, Sahloul University Hospital, 4054 Sousse, Tunisia.,Faculty of Pharmacy, University of Monastir, Monastir, Tunisia
| | - Meriam BenHamida-Rebaï
- LR14SP02, Epidemiology and Immunogenetics of Human Viral Infections, Laboratory of Microbiology, Sahloul University Hospital, 4054 Sousse, Tunisia.,Faculty of Pharmacy, University of Monastir, Monastir, Tunisia
| | - Saoussen Kacem
- LR14SP02, Epidemiology and Immunogenetics of Human Viral Infections, Laboratory of Microbiology, Sahloul University Hospital, 4054 Sousse, Tunisia.,Faculty of Pharmacy, University of Monastir, Monastir, Tunisia
| | - Aida Argoubi
- LR14SP02, Epidemiology and Immunogenetics of Human Viral Infections, Laboratory of Microbiology, Sahloul University Hospital, 4054 Sousse, Tunisia.,Faculty of Pharmacy, University of Monastir, Monastir, Tunisia
| | - Haifa Bennour
- LR14SP02, Epidemiology and Immunogenetics of Human Viral Infections, Laboratory of Microbiology, Sahloul University Hospital, 4054 Sousse, Tunisia
| | - Noureddine Boujaafar
- Faculty of Pharmacy, University of Monastir, Monastir, Tunisia.,Laboratory of Microbiology, Sahloul University Hospital, 4054 Sousse, Tunisia
| | - Abdelhalim Trabelsi
- Faculty of Pharmacy, University of Monastir, Monastir, Tunisia.,LR14SP02, Epidemiology and Immunogenetics of Human Viral Infections, Laboratory of Microbiology, Sahloul University Hospital, 4054 Sousse, Tunisia
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11
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Langa JS, Thompson R, Arnaldo P, Resque HR, Rose T, Enosse SM, Fialho A, de Assis RMS, da Silva MFM, Leite JPG. Epidemiology of rotavirus A diarrhea in Chókwè, Southern Mozambique, from February to September, 2011. J Med Virol 2016; 88:1751-8. [PMID: 27003797 DOI: 10.1002/jmv.24531] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/18/2016] [Indexed: 11/12/2022]
Abstract
Acute diarrhea disease caused by Rotaviruses A (RVA) is still the leading cause of morbidity and mortality in children ≤5 years old in developing countries. An exploratory cross-sectional study was conducted between February and September, 2011 to determine the proportion of acute diarrhea caused by RVA. A total of 254 stool specimens were collected from children ≤5 years old with acute diarrhea, including outpatients (222 children) and inpatients (32 children), in three local health centers in Chókwè District, Gaza Province, South of Mozambique. RVA antigens were detected using enzyme immunoassay (EIA); the RVA G (VP7) and P (VP4) genotypes were determined by RT-PCR or analysis sequencing. Sixty (24%) out of 254 fecal specimens were positive for RVA by EIA; being 58 (97%) from children ≤2 years of age. RVA prevalence peaks in June and July (coldest and drier months) and the G[P] binary combination observed were G12P[8] (57%); G1P[8] (9%); G12P[6] (6%); and 2% for each of the following genotypes: G1P[6], G2P[6] G4P[6], and G9P[8]. Non-Typeable (NT) G and/or P genotypes were observed as follows: G12P [NT] (6%); G1P [NT], G3P[NT] and GNTP[NT] (4%). Considering the different GP combinations, G12 represented 67% of the genotypes. This is the first data showing the diversity of RVA genotypes in Mozambique highlighting the epidemiological importance of these viruses in acute diarrhea cases in children ≤2 years old. In addition, these findings will provide a baseline data before the introduction of the RVA monovalent (Rotarix(®) ) vaccine in the National Immunization Program in September 2015. J. Med. Virol. 88:1751-1758, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Jerónimo S Langa
- Chokwe Health Research and Training Centre (CITSC), National Institute of Health, Maputo, Mozambique.,Laboratory of Comparative and Environmental Virology, Oswaldo Cruz Institute, Fiocruz, Rio de Janeiro, Brazil
| | - Ricardo Thompson
- Chokwe Health Research and Training Centre (CITSC), National Institute of Health, Maputo, Mozambique
| | - Paulo Arnaldo
- Chokwe Health Research and Training Centre (CITSC), National Institute of Health, Maputo, Mozambique
| | - Hugo Reis Resque
- Laboratory of Comparative and Environmental Virology, Oswaldo Cruz Institute, Fiocruz, Rio de Janeiro, Brazil.,Virology Section, Evandro Chagas Institute, Ananindeua, Pará, Brazil
| | - Tatiana Rose
- Laboratory of Comparative and Environmental Virology, Oswaldo Cruz Institute, Fiocruz, Rio de Janeiro, Brazil
| | - Sonia M Enosse
- Chokwe Health Research and Training Centre (CITSC), National Institute of Health, Maputo, Mozambique
| | - Alexandre Fialho
- Laboratory of Comparative and Environmental Virology, Oswaldo Cruz Institute, Fiocruz, Rio de Janeiro, Brazil
| | | | - Marcelle Figueira Marques da Silva
- Laboratory of Comparative and Environmental Virology, Oswaldo Cruz Institute, Fiocruz, Rio de Janeiro, Brazil.,Faculty of Biology, Laboratory of Virus Contaminants of Water and Food, University of Barcelona, Barcelona, Spain
| | - José Paulo Gagliardi Leite
- Laboratory of Comparative and Environmental Virology, Oswaldo Cruz Institute, Fiocruz, Rio de Janeiro, Brazil
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12
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Abstract
SUMMARYGenotype G12 strains are now considered to be the sixth most prevalent human rotaviruses worldwide. In two Sicilian cities, Palermo and Messina, surveillance of rotavirus circulation performed since 1985 and 2009, respectively, did not detect G12 strains until 2012. From 2012 to 2014 rotavirus infection was detected in 29·7% of 1647 stool samples collected from children admitted for acute gastroenteritis to three Sicilian hospitals in Palermo, Messina and Ragusa. In 2012, G12P[8] was first detected in Palermo and then in Messina where it represented the second most frequent genotype (20% prevalence) after G1P[8]. Thereafter, G12 strains continued to circulate in Sicily, showing a marked prevalence in Ragusa (27·8%) in 2013 and in Palermo (21%) and Messina (16·6%) in 2014. All but one of the Sicilian G12 strains carried a P[8] VP4 genotype, whereas the single non-P[8] rotavirus strain was genotyped as G12P[9]. Phylogenetic analysis of the VP7 and VP4 sequences allowed distinction of several genetic lineages and separation of the G12P[8] strains into three cluster combinations. These findings indicate independent introductions of G12 rotavirus strains in Sicily in recent years.
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Agbemabiese CA, Nakagomi T, Doan YH, Nakagomi O. Whole genomic constellation of the first human G8 rotavirus strain detected in Japan. INFECTION GENETICS AND EVOLUTION 2015; 35:184-93. [PMID: 26275468 DOI: 10.1016/j.meegid.2015.07.033] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Revised: 07/28/2015] [Accepted: 07/30/2015] [Indexed: 12/25/2022]
Abstract
Human G8 Rotavirus A (RVA) strains are commonly detected in Africa but are rarely detected in Japan and elsewhere in the world. In this study, the whole genome sequence of the first human G8 RVA strain designated AU109 isolated in a child with acute gastroenteritis in 1994 was determined in order to understand how the strain was generated including the host species origin of its genes. The genotype constellation of AU109 was G8-P[4]-I2-R2-C2-M2-A2-N2-T2-E2-H2. Phylogenetic analyses of the 11 genome segments revealed that its VP7 and VP1 genes were closely related to those of a Hungarian human G8P[14] RVA strain and these genes shared the most recent common ancestors in 1988 and 1982, respectively. AU109 possessed an NSP2 gene closely related to those of Chinese sheep and goat RVA strains. The remaining eight genome segments were closely related to Japanese human G2P[4] strains which circulated around 1985-1990. Bayesian evolutionary analyses revealed that the NSP2 gene of AU109 and those of the Chinese sheep and goat RVA strains diverged from a common ancestor around 1937. In conclusion, AU109 was generated through genetic reassortment event where Japanese DS-1-like G2P[4] strains circulating around 1985-1990 obtained the VP7, VP1 and NSP2 genes from unknown ruminant G8 RVA strains. These observations highlight the need for comprehensive examination of the whole genomes of RVA strains of less explored host species.
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Affiliation(s)
- Chantal Ama Agbemabiese
- Department of Hygiene and Molecular Epidemiology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Toyoko Nakagomi
- Department of Hygiene and Molecular Epidemiology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Yen Hai Doan
- Department of Hygiene and Molecular Epidemiology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Osamu Nakagomi
- Department of Hygiene and Molecular Epidemiology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.
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14
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Evolution of a G6P[6] rotavirus strain isolated from a child with acute gastroenteritis in Ghana, 2012. J Gen Virol 2015; 96:2219-2231. [DOI: 10.1099/vir.0.000174] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
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15
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Wen X, Cao D, Jones RW, Hoshino Y, Yuan L. Tandem truncated rotavirus VP8* subunit protein with T cell epitope as non-replicating parenteral vaccine is highly immunogenic. Hum Vaccin Immunother 2015; 11:2483-9. [PMID: 26091081 PMCID: PMC4635725 DOI: 10.1080/21645515.2015.1054583] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Revised: 05/06/2015] [Accepted: 05/19/2015] [Indexed: 10/23/2022] Open
Abstract
The two currently available live oral rotavirus vaccines, Rotarix(®) and RotaTeq(®), are highly efficacious in the developed countries. However, the efficacy of such vaccines in resource deprived countries in Africa and Southeast Asia is low. We reported previously that a bacterially-expressed rotavirus P2-P[8] ΔVP8* subunit vaccine candidate administered intramuscularly elicited high-titers of neutralizing antibodies in guinea pigs and mice and significantly shortened the duration of diarrhea in neonatal gnotobiotic pigs upon oral challenge with virulent human rotavirus Wa strain. To further improve its vaccine potential and provide wider coverage against rotavirus strains of global and regional epidemiologic importance, we constructed 2 tandem recombinant VP8* proteins, P2-P[8] ΔVP8*-P[8] ΔVP8* and P2-P[8] ΔVP8*-P[6] ΔVP8* based on Escherichia coli expression system. The two resulting recombinant tandem proteins were highly soluble and P2-P[8] ΔVP8*-P[8] ΔVP8* was generated with high yield. Moreover, guinea pigs immunized intramuscularly by 3 doses of the P2-P[8] ΔVP8*-P[8] ΔVP8* or P2-P[8] ΔVP8*-P[6] ΔVP8* vaccine with aluminum phosphate adjuvant developed high titers of homotypic and heterotypic neutralizing antibodies against human rotaviruses bearing G1-G4, G8, G9 and G12 with P[8], P[4] or P[6] combination. The results suggest that these 2 subunit vaccines in monovalent or bivalent formulation can provide antigenic coverage to almost all the rotavirus G (VP7) types and major P (VP4) types of global as well as regional epidemiologic importance.
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MESH Headings
- Adjuvants, Immunologic/administration & dosage
- Aluminum Compounds/administration & dosage
- Animals
- Antibodies, Neutralizing/blood
- Antibodies, Viral/blood
- Epitopes, T-Lymphocyte/genetics
- Epitopes, T-Lymphocyte/immunology
- Escherichia coli/genetics
- Female
- Gene Expression
- Guinea Pigs
- Injections, Intramuscular
- Mutant Proteins/genetics
- Mutant Proteins/immunology
- Phosphates/administration & dosage
- RNA-Binding Proteins/genetics
- RNA-Binding Proteins/immunology
- Recombinant Proteins/genetics
- Recombinant Proteins/immunology
- Rotavirus Vaccines/administration & dosage
- Rotavirus Vaccines/genetics
- Rotavirus Vaccines/immunology
- Vaccines, Subunit/administration & dosage
- Vaccines, Subunit/genetics
- Vaccines, Subunit/immunology
- Vaccines, Synthetic/administration & dosage
- Vaccines, Synthetic/genetics
- Vaccines, Synthetic/immunology
- Viral Nonstructural Proteins/genetics
- Viral Nonstructural Proteins/immunology
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Affiliation(s)
- Xiaobo Wen
- College of Animal Science & Veterinary Medicine; Heilongjiang Bayi Agricultural University; Daqing, Heilongjiang Province, China
| | - Dianjun Cao
- Department of Biomedical Sciences and Pathobiology; Virginia-Maryland College of Veterinary Medicine; Virginia Polytechnic Institute and State University; Blacksburg, VA USA
| | - Ronald W Jones
- Rotavirus Vaccine Development Section; Laboratory of Infectious Diseases; National Institute of Allergy and Infectious Diseases; National Institutes of Health; Bethesda, MD USA
| | - Yasutaka Hoshino
- Rotavirus Vaccine Development Section; Laboratory of Infectious Diseases; National Institute of Allergy and Infectious Diseases; National Institutes of Health; Bethesda, MD USA
| | - Lijuan Yuan
- Department of Biomedical Sciences and Pathobiology; Virginia-Maryland College of Veterinary Medicine; Virginia Polytechnic Institute and State University; Blacksburg, VA USA
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16
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Ndze VN, Esona MD, Achidi EA, Gonsu KH, Dóró R, Marton S, Farkas S, Ngeng MB, Ngu AF, Obama-Abena MT, Bányai K. Full genome characterization of human Rotavirus A strains isolated in Cameroon, 2010–2011: Diverse combinations of the G and P genes and lack of reassortment of the backbone genes. INFECTION GENETICS AND EVOLUTION 2014; 28:537-60. [DOI: 10.1016/j.meegid.2014.10.009] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Revised: 10/09/2014] [Accepted: 10/11/2014] [Indexed: 12/17/2022]
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17
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Boula A, Waku-Kouomou D, Njiki Kinkela M, Esona MD, Kemajou G, Mekontso D, Seheri M, Ndze VN, Emah I, Ela S, Dahl BA, Kobela M, Cavallaro KF, Etoundi Mballa GA, Genstch JR, Bowen MD, Koki Ndombo P. Molecular surveillance of rotavirus strains circulating in Yaoundé, Cameroon, September 2007-December 2012. INFECTION GENETICS AND EVOLUTION 2014; 28:470-5. [PMID: 25220619 DOI: 10.1016/j.meegid.2014.08.019] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Revised: 08/15/2014] [Accepted: 08/19/2014] [Indexed: 10/24/2022]
Abstract
Rotavirus is the most common cause of severe diarrheal disease in children under 5 years of age worldwide. The World Health Organization (WHO) estimated that 453,000 rotavirus-attributable deaths occur annually. Through the WHO, the Rotavirus Sentinel Surveillance Program was established in Cameroon in September 2007 with the Mother and Child Center (MCC) in Yaoundé playing the role of sentinel site and national laboratory for this program. The objectives of this surveillance were to assess the rotavirus disease burden and collect baseline information on rotavirus strains circulating in Cameroon. Diarrheal stool samples were collected in a pediatric hospital from children under 5, using the WHO case definition for rotavirus diarrhea. Antigen detection of rotavirus was performed by using an enzyme immunoassay (EIA). The genotypic characterization was performed using multiplexed semi-nested reverse transcription-polymerase chain reaction (RT-PCR) assays. Between September 2007 and December 2012, 2444 stool samples were received at the MCC laboratory for rotavirus antigen detection, of which 999 (41%) were EIA positive. Among EIA positive samples 898 were genotyped. Genotype prevalence varied each year. Genotype G9P[8] was the dominant type during 2007 (32%) and 2008 (24%), genotype G3P[6] predominated in 2010 (36%) and 2011 (25%), and G1P[8] was predominant in 2012 (44%). The findings showed that the rotavirus disease burden is high and there is a broad range of rotavirus strains circulating in Yaoundé. These data will help measure the impact of vaccination in the future.
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Affiliation(s)
- Angeline Boula
- Mother and Child Center, Chantal Biya Foundation, Yaoundé, Cameroon
| | - Diane Waku-Kouomou
- Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30333, United States.
| | | | - Mathew D Esona
- Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30333, United States
| | - Grace Kemajou
- Mother and Child Center, Chantal Biya Foundation, Yaoundé, Cameroon
| | - David Mekontso
- World Health Organization Country Office of Cameroon, Yaoundé, Cameroon
| | - Mapaseka Seheri
- Medical Research Council/Diarrhoeal Pathogens Research Unit, University of Limpopo, Medunsa Campus, South Africa
| | | | - Irene Emah
- Ministry of Health, Expanded Program on Immunization, Yaoundé, Cameroon
| | - Serge Ela
- Mother and Child Center, Chantal Biya Foundation, Yaoundé, Cameroon
| | - Benjamin A Dahl
- Global Immunization Division, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA 30333, United States
| | - Marie Kobela
- Ministry of Health, Expanded Program on Immunization, Yaoundé, Cameroon
| | - Kathleen F Cavallaro
- Global Immunization Division, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA 30333, United States
| | | | - Jon R Genstch
- Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30333, United States
| | - Michael D Bowen
- Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30333, United States
| | - Paul Koki Ndombo
- Mother and Child Center, Chantal Biya Foundation, Yaoundé, Cameroon
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18
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Komoto S, Wandera Apondi E, Shah M, Odoyo E, Nyangao J, Tomita M, Wakuda M, Maeno Y, Shirato H, Tsuji T, Ichinose Y, Taniguchi K. Whole genomic analysis of human G12P[6] and G12P[8] rotavirus strains that have emerged in Kenya: identification of porcine-like NSP4 genes. INFECTION GENETICS AND EVOLUTION 2014; 27:277-93. [PMID: 25111611 DOI: 10.1016/j.meegid.2014.08.002] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Revised: 07/24/2014] [Accepted: 08/01/2014] [Indexed: 02/03/2023]
Abstract
G12 rotaviruses are globally emerging rotavirus strains causing severe childhood diarrhea. However, the whole genomes of only a few G12 strains have been fully sequenced and analyzed, of which only one G12P[4] and one G12P[6] are from Africa. In this study, we sequenced and characterized the complete genomes of three G12 strains (RVA/Human-tc/KEN/KDH633/2010/G12P[6], RVA/Human-tc/KEN/KDH651/2010/G12P[8], and RVA/Human-tc/KEN/KDH684/2010/G12P[6]) identified in three stool specimens from children with acute diarrhea in Kenya, Africa. On whole genomic analysis, all three Kenyan G12 strains were found to have a Wa-like genetic backbone: G12-P[6]-I1-R1-C1-M1-A1-N1-T1-E1-H1 (strains KDH633 and KDH684) and G12-P[8]-I1-R1-C1-M1-A1-N1-T1-E1-H1 (strain KDH651). Phylogenetic analysis showed that most genes of the three strains examined in this study were genetically related to globally circulating human G1, G9, and G12 strains. Of note is that the NSP4 genes of strains KDH633 and KDH684 appeared to be of porcine origin, suggesting the occurrence of reassortment between human and porcine strains. Furthermore, strains KDH633 and KDH684 were very closely related to each other in all the 11 gene segments, indicating derivation of the two strains from a common origin. On the other hand, strain KDH651 consistently formed distinct clusters of 10 of the 11 gene segments (VP1-2, VP4, VP6-7, and NSP1-5), indicating a distinct origin of strain KDH651 from that of strains KDH633 and KDH684. To our knowledge, this is the first report on whole genome-based characterization of G12 strains that have emerged in Kenya. Our observations will provide important insights into the evolutionary dynamics of emerging G12 rotaviruses in Africa.
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Affiliation(s)
- Satoshi Komoto
- Department of Virology and Parasitology, Fujita Health University School of Medicine, Toyoake, Aichi 470-1192, Japan.
| | - Ernest Wandera Apondi
- Kenya Research Station, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nairobi 19993-00202, Kenya
| | - Mohammad Shah
- Kenya Research Station, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nairobi 19993-00202, Kenya
| | - Erick Odoyo
- Kenya Research Station, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nairobi 19993-00202, Kenya
| | - James Nyangao
- Center for Virus Research, Kenya Medical Research Institute (KEMRI), Nairobi 54840-00200, Kenya
| | - Mayuko Tomita
- Department of Virology and Parasitology, Fujita Health University School of Medicine, Toyoake, Aichi 470-1192, Japan
| | - Mitsutaka Wakuda
- Department of Virology and Parasitology, Fujita Health University School of Medicine, Toyoake, Aichi 470-1192, Japan
| | - Yoshimasa Maeno
- Department of Virology and Parasitology, Fujita Health University School of Medicine, Toyoake, Aichi 470-1192, Japan
| | - Haruko Shirato
- Department of Virology II, National Institute of Infectious Diseases, Musashi-Murayama, Tokyo 208-0011, Japan
| | - Takao Tsuji
- Department of Microbiology, Fujita Health University School of Medicine, Toyoake, Aichi 470-1192, Japan
| | - Yoshio Ichinose
- Kenya Research Station, Institute of Tropical Medicine (NEKKEN), Nagasaki University, Nairobi 19993-00202, Kenya
| | - Koki Taniguchi
- Department of Virology and Parasitology, Fujita Health University School of Medicine, Toyoake, Aichi 470-1192, Japan
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19
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Moyo SJ, Blomberg B, Hanevik K, Kommedal O, Vainio K, Maselle SY, Langeland N. Genetic diversity of circulating rotavirus strains in Tanzania prior to the introduction of vaccination. PLoS One 2014; 9:e97562. [PMID: 24844631 PMCID: PMC4028215 DOI: 10.1371/journal.pone.0097562] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Accepted: 04/21/2014] [Indexed: 12/25/2022] Open
Abstract
Background Tanzania currently rolls out vaccination against rotavirus-diarrhea, a major cause of child illness and death. As the vaccine covers a limited number of rotavirus variants, this study describes the molecular epidemiology of rotavirus among children under two years in Dar es Salaam, Tanzania, prior to implementation of vaccination. Methods Stool specimens, demographic and clinical information, were collected from 690 children admitted to hospital due to diarrhea (cases) and 545 children without diarrhea (controls) during one year. Controls were inpatient or children attending child health clinics. Rotavirus antigen was detected using ELISA and positive samples were typed by multiplex semi-nested PCR and sequencing. Results The prevalence of rotavirus was higher in cases (32.5%) than in controls (7.7%, P<0.001). The most common G genotypes were G1 followed by G8, G12, and G4 in cases and G1, G12 and G8 in controls. The Tanzanian G1 variants displayed 94% similarity with the Rotarix vaccine G1 variant. The commonest P genotypes were P[8], P[4] and P[6], and the commonest G/P combination G1 P[8] (n = 123), G8 P[4] and G12 P[6]. Overall, rotavirus prevalence was higher in cool (23.9%) than hot months (17.1%) of the year (P = 0.012). We also observed significant seasonal variation of G genotypes. Rotavirus was most frequently found in the age group of four to six months. The prevalence of rotavirus in cases was lower in stunted children (28.9%) than in non-stunted children (40.1%, P = 0.003) and lower in HIV-infected (15.4%, 4/26) than in HIV-uninfected children (55.3%, 42/76, P<0.001). Conclusion This pre-vaccination study shows predominance of genotype G1 in Tanzania, which is phylogenetically distantly related to the vaccine strains. We confirm the emergence of genotype G8 and G12. Rotavirus infection and circulating genotypes showed seasonal variation. This study also suggests that rotavirus may not be an opportunistic pathogen in children infected with HIV.
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Affiliation(s)
- Sabrina J. Moyo
- Department of Clinical Science, University of Bergen, Bergen, Norway
- Department of Microbiology and Immunology, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
- * E-mail:
| | - Bjørn Blomberg
- Department of Clinical Science, University of Bergen, Bergen, Norway
- Centre for Tropical Infectious Diseases, Haukeland University Hospital, Bergen, Norway
| | - Kurt Hanevik
- Department of Clinical Science, University of Bergen, Bergen, Norway
- Centre for Tropical Infectious Diseases, Haukeland University Hospital, Bergen, Norway
| | - Oyvind Kommedal
- Department of Microbiology, Haukeland University Hospital, Bergen, Norway
| | - Kirsti Vainio
- Division of Infectious Disease Control, Norwegian Institute of Public Health, Oslo, Norway
| | - Samuel Y. Maselle
- Department of Microbiology and Immunology, Muhimbili University of Health and Allied Sciences, Dar es Salaam, Tanzania
| | - Nina Langeland
- Department of Clinical Science, University of Bergen, Bergen, Norway
- Department of Medicine, Haukeland University Hospital, Bergen, Norway
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Ndze VN, Papp H, Achidi EA, Gonsu KH, László B, Farkas S, Kisfali P, Melegh B, Esona MD, Bowen MD, Bányai K, Gentsch JR, Odama AMT. One year survey of human rotavirus strains suggests the emergence of genotype G12 in Cameroon. J Med Virol 2013; 85:1485-90. [PMID: 23765785 DOI: 10.1002/jmv.23603] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/25/2013] [Indexed: 01/13/2023]
Abstract
In this study the emergence of rotavirus A genotype G12 in children <5 years of age is reported from Cameroon during 2010/2011. A total of 135 human stool samples were P and G genotyped by reverse transcriptase PCR. Six different rotavirus VP7 genotypes were detected, including G1, G2, G3, G8, G9, and G12 in combinations with P[4], P[6] and P[8] VP4 genotypes. Genotype G12 predominated in combination with P[8] (54.1%) and P[6] (10.4%) genotypes followed by G1P[6] (8.2%), G3P[6] (6.7%), G2P[4] (5.9%), G8P[6] (3.7%), G2P[6] (0.7%), G3P[8] (0.7%), and G9P[8] (0.7%). Genotype P[6] strains in combination with various G-types represented a substantial proportion (N=44, 32.6%) of the genotyped strains. Partially typed strains included G12P[NT] (2.2%); G3P[NT] (0.7%); G(NT)P[6] (1.5%); and G(NT)P[8] (0.7%). Mixed infections were found in five specimens (3.7%) in several combinations including G1+ G12P[6], G2+ G3P[6] + P[8], G3+ G8P[6], G3 + G12P[6] + P[8], and G12P[6] +P[8]. The approximately 10% relative frequency of G12P[6] strains detected in this study suggests that this strain is emerging in Cameroon and should be monitored carefully as rotavirus vaccine is implemented in this country, as it shares neither G- nor P-type specificity with strains in the RotaTeq® and Rotarix® vaccines. These findings are consistent with other recent reports of the global spread and increasing epidemiologic importance of G12 and P[6] strains.
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Razafindratsimandresy R, Heraud JM, Ramarokoto CE, Rabemanantsoa S, Randremanana R, Andriamamonjy NS, Richard V, Reynes JM. Rotavirus genotypes in children in the community with diarrhea in Madagascar. J Med Virol 2013; 85:1652-60. [PMID: 23797859 DOI: 10.1002/jmv.23631] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/20/2013] [Indexed: 12/11/2022]
Abstract
In the context of the possible introduction of a preventive vaccine against rotaviruses in Madagascar, the G and P genotypes distribution of the rotaviruses circulating in the children in Madagascar was studied, and the presence of emerging genotypes and unusual strains were assessed. From February 2008 to May 2009, 1,679 stools specimens were collected from children ≤5 years old with diarrhea. ELISA was used for antigen detection, and molecular amplification of VP7 and VP4 gene fragments was used for genotyping. Rotavirus antigen was detected in 104 samples (6.2%). Partial sequences of VP7 and VP4 genes were obtained from 81 and 80 antigen-positive stools, respectively. The most frequent G and P types combinations detected were G9P[8] (n = 51; 64.6%), followed by G1P[8] (n = 15; 18.9%), and G1P[6] (n = 8; 10.1%). A few unusual G-P combinations, such as G4P[6] (n = 3; 3.8%), G9P[6] (n = 1; 1.3%), and G3P[9] reassortant feline human virus (n = 1; 1.3%) were identified. Both VP4 and VP7 sequences in one of the three G4P[6] isolates were closely related to those in porcine strains, and one was a reassortant human porcine virus. These findings give an overview of the strains circulating in Madagascar and should help public health authorities to define a vaccine strategy.
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Kokkinos PA, Ziros PG, Monini M, Lampropoulou P, Karampini A, Papachatzi E, Mantagos S, Ruggeri FM, Vantarakis A. Rare types of rotaviruses isolated from children with acute gastroenteritis in Patras, Greece. Intervirology 2013; 56:237-41. [PMID: 23774743 DOI: 10.1159/000351183] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2012] [Accepted: 04/04/2013] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Acute diarrhea remains a major public health issue worldwide, with gastroenteritis agents associated with a high morbidity, especially in infants and young children. A 1-year study (2009-2010) of rotavirus (RV)-caused pediatric diarrhea was performed on hospitalized children admitted with symptoms of acute diarrhea to the University Hospital of Patras, Greece. METHODS Twenty-nine fecal samples were investigated for RVs, adenoviruses (AdVs), and enteroviruses (EVs) in an attempt to characterize these enteric viruses, which have been implicated in hospitalized diarrhea. RESULTS A 44.8% (13/29) incidence of viral infection was reported for the viral targets. Monoinfections accounted for 31% (9/29), while bi-infections accounted for 13.4% (4/29). Sequencing of positive samples allowed identification of RVs G4P[8] (2/29), G9P[8] (1/29), and interestingly of the rare type G12P[8] (2/29). AdV types 1, 2, and 6 were also identified in 4/29, 1/29, and 1/29 of the samples, respectively. Regarding the EVs, EV71 (2/29), coxsackievirus A4 (1/29), echovirus 11 (1/29), and EV96 (1/29) were typed. CONCLUSION The results of the present study, and specifically the detection of rare RV G12 and EV71 strains, address the need for continuous epidemiological surveys to provide epidemiological pictures of pediatric viral infections circulating in the community.
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Affiliation(s)
- Petros A Kokkinos
- Environmental Microbiology Unit, Department of Public Health, School of Medicine, University of Patras, Patras, Greece
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Turner A, Ngwira B, Witte D, Mwapasa M, Dove W, Cunliffe N. Surveillance of rotavirus gastro-enteritis in children in Blantyre, Malawi. Paediatr Int Child Health 2013; 33:42-5. [PMID: 23485495 DOI: 10.1179/2046905512y.0000000015] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
BACKGROUND Rotavirus is a leading cause of acute gastro-enteritis in infants and young children worldwide. Previous studies of rotavirus gastro-enteritis in Malawi have documented a high disease burden with an extensive diversity of circulating rotavirus strains. METHODS In anticipation of the introduction of national rotavirus vaccination, a 2-year surveillance study was undertaken in 2008 and 2009 of children in Blantyre seeking hospital care for acute gastro-enteritis. Rotavirus was detected in faecal specimens by ELISA. Rotavirus G and P types were determined by RT-PCR. RESULTS Rotavirus, which circulated throughout the year, was detected in 220/720 (31%) children. Over 85% of patients with rotavirus gastro-enteritis were <1 year of age. A total of 13 rotavirus G/P types were identified, the most common strains being G1P[8] (39·5%), G12P[6] (23·2%), G2P[4] (9·5%), G9P[8] (6·8%) and G8P[4] (6·4%). CONCLUSIONS The data confirm the importance of rotavirus infection in young Malawian children and highlight the continuing diversity of circulating rotavirus strains in Blantyre. Together with previous observations, the findings contribute to a baseline of data against which the impact of future rotavirus vaccination in Malawi can be assessed.
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Affiliation(s)
- Ann Turner
- Department of Clinical Infection, Microbiology & Immunology, Institute of Infection & Global Health, University of Liverpool, UK
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Oluwatoyin Japhet M, Adeyemi Adesina O, Famurewa O, Svensson L, Nordgren J. Molecular epidemiology of rotavirus and norovirus in Ile-Ife, Nigeria: high prevalence of G12P[8] rotavirus strains and detection of a rare norovirus genotype. J Med Virol 2012; 84:1489-96. [PMID: 22825829 DOI: 10.1002/jmv.23343] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Rotavirus (RV) and norovirus (NoV) are considered the most common causes of viral gastroenteritis in children. In this study, the prevalence of RV and NoV infection in 55 children with diarrhea from the rural community Akinlalu in Southwestern Nigeria was investigated using real-time PCR assays. The RV and NoV strains were genotyped by PCR and/or sequencing. RV and NoV infections occurred with a prevalence of 34.5% and 25.5% respectively, with predominance in children <1 year. Most infections occurred during the dry season with increasing prevalence of RV as the dry season progressed (October-January). Infections with RV VP6 subgroup (SG) II were more prevalent (27.3%) than SGI (7.3%). Similarly, NoV genogroup II infections were more common (23.6%) than genogroup I (1.8%). Five children out of 55 (9.1%) were co-infected with both RV and NoV. Notably, G12P[8] was the predominant RV strain (36.8%, n = 7), observed for the first time in Nigeria. The VP7 gene of the G12 strains clustered within lineage III, sharing high nucleotide identity with each other (>99%) indicating introduction in Nigeria from a single donor. Furthermore, a putative novel genotype within genogroup I NoV was detected, which till date has only been reported once in humans. To conclude, a high prevalence of the emerging G12P[8] RV strain was observed for the first time in Nigeria, as well as a putative novel NoV genotype in humans. These results provide new information which can be important for future vaccine evaluations and possible introduction in Nigeria.
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Chigor VN, Okoh AI. Quantitative RT-PCR detection of hepatitis A virus, rotaviruses and enteroviruses in the Buffalo River and source water dams in the Eastern Cape Province of South Africa. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2012. [PMID: 23202829 PMCID: PMC3524610 DOI: 10.3390/ijerph9114017] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Human enteric viruses (HEntVs) are a major cause of water-related diseases. The prevalence of hepatitis A virus (HAV), rotaviruses (RoV) and enteroviruses (EnV) in Buffalo River waters was assessed quantitatively over a period of 12 months (August 2010 to July 2011). Seventy-two samples were collected from six sites, including three dams, and concentrated using the adsorption-elution method. Viral RNA was extracted using a commercial kit, and the viruses were quantified by real-time quantitative reverse transcriptase PCR (RT-qPCR). Two or more viruses were detected in 12.5% of the samples. HAV was detected in 43.1% of the samples and in significantly (p < 0.05) varying concentrations of 1.5 × 10(1)–1.9 × 10(5) genome copies/L compared to RoV and EnV, while RoVs were detected in 13.9% of samples, with concentrations ranging from 2.5 × 10(1)–2.1 × 10(3) genome copies/L, and EnV were detected in 9.7% of the samples, with concentrations ranging from 1.3 × 10(1)–8.6 × 10(1) genome copies/L. Only HAV was detected at all the sites, with the Bridle Drift Dam recording significantly higher (p < 0.05) concentrations. The presence of enteric viruses in Buffalo River may constitute public health risks and the incidence of HAV at all the sites could reflect both the epidemiological status of hepatitis A and HAV persistence in the water environments.
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Affiliation(s)
- Vincent Nnamdigadi Chigor
- Applied and Environmental Microbiology Research Group (AEMREG), Department of Biochemistry and Microbiology, University of Fort Hare, Private Bag X1314, Alice 5700, Eastern Cape, South Africa.
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Steele AD, Neuzil KM, Cunliffe NA, Madhi SA, Bos P, Ngwira B, Witte D, Todd S, Louw C, Kirsten M, Aspinall S, Van Doorn LJ, Bouckenooghe A, Suryakiran PV, Han HH. Human rotavirus vaccine Rotarix™ provides protection against diverse circulating rotavirus strains in African infants: a randomized controlled trial. BMC Infect Dis 2012; 12:213. [PMID: 22974466 PMCID: PMC3462149 DOI: 10.1186/1471-2334-12-213] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2011] [Accepted: 08/22/2012] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Rotaviruses are the most important cause of severe acute gastroenteritis worldwide in children <5 years of age. The human, G1P[8] rotavirus vaccine Rotarix™ significantly reduced severe rotavirus gastroenteritis episodes in a Phase III clinical trial conducted in infants in South Africa and Malawi. This paper examines rotavirus vaccine efficacy in preventing severe rotavirus gastroenteritis, during infancy, caused by the various G and P rotavirus types encountered during the first rotavirus-season. METHODS Healthy infants aged 5-10 weeks were enrolled and randomized into three groups to receive either two (10 and 14 weeks) or three doses of Rotarix™ (together forming the pooled Rotarix™ group) or three doses of placebo at a 6,10,14-week schedule. Weekly home visits were conducted to identify gastroenteritis episodes. Rotaviruses were detected by ELISA and genotyped by RT-PCR and nucleotide sequencing. The percentage of infants with severe rotavirus gastroenteritis caused by the circulating G and P types from 2 weeks post-last dose until one year of age and the corresponding vaccine efficacy was calculated with 95% CI. RESULTS Overall, 4939 infants were vaccinated and 4417 (pooled Rotarix™ = 2974; placebo = 1443) were included in the per protocol efficacy cohort. G1 wild-type was detected in 23 (1.6%) severe rotavirus gastroenteritis episodes from the placebo group. This was followed in order of detection by G12 (15 [1%] in placebo) and G8 types (15 [1%] in placebo). Vaccine efficacy against G1 wild-type, G12 and G8 types were 64.1% (95% CI: 29.9%; 82%), 51.5% (95% CI:-6.5%; 77.9%) and 64.4% (95% CI: 17.1%; 85.2%), respectively. Genotype P[8] was the predominant circulating P type and was detected in 38 (2.6%) severe rotavirus gastroenteritis cases in placebo group. The remaining circulating P types comprised of P[4] (20 [1.4%] in placebo) and P[6] (13 [0.9%] in placebo). Vaccine efficacy against P[8] was 59.1% (95% CI: 32.8%; 75.3%), P[4] was 70.9% (95% CI: 37.5%; 87.0%) and P[6] was 55.2% (95% CI: -6.5%; 81.3%) CONCLUSIONS Rotarix™ vaccine demonstrated efficacy against severe gastroenteritis caused by diverse circulating rotavirus types. These data add to a growing body of evidence supporting heterotypic protection provided by Rotarix™. TRIAL REGISTRATION NUMBER NCT00241644.
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Affiliation(s)
- Andrew Duncan Steele
- Rotavirus Vaccine Program, PATH, 2201 Westlake Ave, Seattle, WA, 98121, USA
- Initiative for Vaccine Research, WHO, 22 Appia Ave, Geneva, 1211, Switzerland
| | - Kathleen M Neuzil
- Rotavirus Vaccine Program, PATH, 2201 Westlake Ave, Seattle, WA, 98121, USA
| | - Nigel A Cunliffe
- Department of Clinical Infection, Microbiology & Immunology, Institute of Infection and Global Health, University of Liverpool, Liverpool, England
| | - Shabir A Madhi
- National Institute for Communicable Diseases: a division of National Health Laboratory Services, Sandringham, South Africa
- Department of Science and Technology National Research Foundation: Vaccine Preventable Diseases, University of the Witwatersrand, Johannesburg, South Africa
| | - Pieter Bos
- MRC Diarrhoeal Pathogens Research Unit, University of Limpopo, Limpopo, South Africa
| | - Bagrey Ngwira
- Department of Community Health, College of Medicine, Blantyre, Malawi
| | - Desiree Witte
- Department of Clinical Infection, Microbiology & Immunology, Institute of Infection and Global Health, University of Liverpool, Liverpool, England
- Department of Community Health, College of Medicine, Blantyre, Malawi
| | - Stacy Todd
- Department of Clinical Infection, Microbiology & Immunology, Institute of Infection and Global Health, University of Liverpool, Liverpool, England
| | - Cheryl Louw
- Madibeng Centre for Research, Brits, South Africa
| | - Mari Kirsten
- Department of Paediatric Surgery, University of Pretoria, Pretoria, RSA
| | - Sanet Aspinall
- Synexus Clinical Research SA/Rota Consortium, Pretoria, South Africa
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Wen X, Cao D, Jones RW, Li J, Szu S, Hoshino Y. Construction and characterization of human rotavirus recombinant VP8* subunit parenteral vaccine candidates. Vaccine 2012; 30:6121-6. [PMID: 22885016 DOI: 10.1016/j.vaccine.2012.07.078] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2012] [Revised: 05/14/2012] [Accepted: 07/30/2012] [Indexed: 11/16/2022]
Abstract
Two currently licensed live oral rotavirus vaccines (Rotarix® and RotaTeq®) are highly efficacious against severe rotavirus diarrhea. However, the efficacy of such vaccines in selected low-income African and Asian countries is much lower than that in middle or high-income countries. Additionally, these two vaccines have recently been associated with rare case of intussusception in vaccinated infants. We developed a novel recombinant subunit parenteral rotavirus vaccine which may be more effective in low-income countries and also avert the potential problem of intussusception. Truncated recombinant VP8* (ΔVP8*) protein of human rotavirus strain Wa P[8], DS-1 P[4] or 1076 P[6] expressed in Escherichia coli was highly soluble and was generated in high yield. Guinea pigs hyperimmunized intramuscularly with each of the ΔVP8* proteins (i.e., P[8], P[4] or P[6]) developed high levels of homotypic as well as variable levels of heterotypic neutralizing antibodies. Moreover, the selected ΔVP8* proteins when administered to mice at a clinically relevant dosage, route and schedule, elicited high levels of serum anti-VP8* IgG and/or neutralizing antibodies. Our data indicated that the ΔVP8* proteins may be a plausible additional candidate as new parenteral rotavirus vaccines.
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Affiliation(s)
- Xiaobo Wen
- Rotavirus Vaccine Development Section, Laboratory of Infectious Diseases, NIAID, National Institutes of Health, Bethesda, MD 20892, USA
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Anderson EJ, Katz BZ, Polin JA, Reddy S, Weinrobe MH, Noskin GA. Rotavirus in adults requiring hospitalization. J Infect 2011; 64:89-95. [PMID: 21939687 DOI: 10.1016/j.jinf.2011.09.003] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2011] [Revised: 09/02/2011] [Accepted: 09/10/2011] [Indexed: 11/29/2022]
Abstract
OBJECTIVES To determine the prevalence and epidemiological characteristics of rotavirus among adults admitted to the hospital with diarrhea that have bacterial stool cultures sent. METHODS The prevalence of rotavirus was determined by Rotaclone EIA in samples submitted for bacterial stool culture from adults requiring hospitalization at Northwestern Memorial Hospital, Chicago from December 01, 2005-November 30, 2006. RESULTS Rotavirus was detected in 2.9% of eligible bacterial stool cultures. A bacterial pathogen (e.g., Salmonella, Shigella, Campylobacter) was identified in 3.3%. Bacterial stool pathogens were more common from June-October while rotavirus was 2.4 times more common than all bacterial pathogens from February-May. Adults in whom rotavirus was detected were older (p < 0.05) and more often immunosuppressed (p < 0.02), particularly with HIV (p < 0.04) compared to individuals from whom bacteria were isolated. The duration of hospitalization and the number of invasive procedures performed in those with rotavirus and bacterial diarrhea were comparable. CONCLUSIONS In the era immediately prior to widespread rotavirus vaccination of children, rotavirus was as commonly detected from adults admitted to the hospital with diarrhea as are the bacterial gastroenteritis pathogens. Rotavirus is particularly prevalent from February-May (as in children) and in immunosuppressed or older adults.
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Affiliation(s)
- Evan J Anderson
- Department of Pediatrics, Northwestern University Feinberg School of Medicine, Division of Pediatric Infectious Diseases, Children's Memorial Hospital, Box #20, 2300 Children's Plaza, Chicago, IL 60614, USA.
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Wu FT, Bányai K, Huang JC, Wu HS, Chang FY, Hsiung CA, Huang YC, Lin JS, Hwang KP, Jiang B, Gentsch JR. Human infection with novel G3P[25] rotavirus strain in Taiwan. Clin Microbiol Infect 2011; 17:1570-3. [PMID: 21851477 DOI: 10.1111/j.1469-0691.2011.03531.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Genotype P[25] rotaviruses are rare and to date have been reported to occur only in a few countries of mainland Asia. Here we report the molecular characterization of a novel human rotavirus genotype combination, G3P[25], detected in a 17-month-old child hospitalized due to severe gastroenteritis during 2009 in central Taiwan. Sequencing and phylogenetic analysis of the VP4 gene demonstrated a distinct origin from other strains bearing the P[25] VP4 gene, whereas the VP7, VP6 and NSP4 gene phylogenies identified common origins with cognate genes of other, presumed human-porcine reassortment Taiwanese strains. These results suggest that interactions between human and animal strains appear to contribute to the generation of genetic and antigenic diversity of rotavirus strains, with potential public health importance in Taiwan.
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Affiliation(s)
- F-T Wu
- Department of Health, Centre for Research and Diagnostics, Centres for Disease Control, Taiwan.
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Than VT, Le VP, Lim I, Kim W. Complete genomic characterization of cell culture adapted human G12P[6] rotaviruses isolated from South Korea. Virus Genes 2011; 42:317-22. [DOI: 10.1007/s11262-011-0576-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2010] [Accepted: 01/17/2011] [Indexed: 01/24/2023]
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Molecular characterization of rare G12P[6] rotavirus isolates closely related to G12 strains from the United States, CAU 195 and CAU 214. Arch Virol 2010; 156:511-6. [PMID: 21132336 DOI: 10.1007/s00705-010-0865-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2010] [Accepted: 11/13/2010] [Indexed: 01/28/2023]
Abstract
Two human G12 rotaviruses, CAU 195 and CAU 214, were isolated from South Korea using cell culture and characterized on the basis of sequence divergence in the VP7, VP4, and NSP4 genes. Phylogenetic analysis of the VP7 gene sequences indicated that these strains clustered into lineage III and were most closely related to G12 rotaviruses isolated in the United States. The VP4 and NSP4 gene sequences showed that two strains belonged to the P[6]-Ia lineage and genotype [B]. This finding provides information that can be used to evaluate G12 strains and aid in the development of effective vaccines in the future.
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Berry SA, Johns B, Shih C, Berry AA, Walker DG. The cost-effectiveness of rotavirus vaccination in Malawi. J Infect Dis 2010; 202 Suppl:S108-15. [PMID: 20684689 DOI: 10.1086/653578] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
BACKGROUND Rotarix (GlaxoSmithKline), a newly licensed rotavirus vaccine requiring 2 doses, may have the potential to save hundreds of thousands of lives in Africa. Nations such as Malawi, where Rotarix is currently under phase III investigation, may nevertheless face difficult economic choices in considering vaccine adoption. METHODS The cost-effectiveness of implementing a Rotarix vaccine program in Malawi was estimated using published estimates of rotavirus burden, vaccine efficacy, and health care utilization and costs. RESULTS With 49.5% vaccine efficacy, a Rotarix program could avert 2582 deaths annually. With GAVI Alliance cofinancing, adoption of Rotarix would be associated with a cost of $5.07 per disability-adjusted life-year averted. With market pricing, Rotarix would be associated with a base case cost of $74.73 per disability-adjusted life-year averted. Key variables influencing results were vaccine efficacy, under-2 rotavirus mortality, and program cost of administering each dose. CONCLUSIONS Adopting Rotarix would likely be highly cost-effective for Malawi, particularly with GAVI support. This finding holds true across uncertainty ranges for key variables, including efficacy, for which data are becoming available.
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Affiliation(s)
- Stephen A Berry
- Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA.
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Grimwood K, Lambert SB, Milne RJ. Rotavirus infections and vaccines: burden of illness and potential impact of vaccination. Paediatr Drugs 2010; 12:235-56. [PMID: 20593908 DOI: 10.2165/11537200-000000000-00000] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Rotaviruses are the most common cause of severe gastroenteritis in children. By 5 years of age virtually every child worldwide will have experienced at least one rotavirus infection. This leads to an enormous disease burden, where every minute a child dies because of rotavirus infection and another four are hospitalized, at an annual societal cost in 2007 of $US2 billion. Most of the annual 527 000 deaths are in malnourished infants living in rural regions of low and middle income countries. In contrast, most measurable costs arise from medical expenses and lost parental wages in high income countries. Vaccines are the only public health prevention strategy likely to control rotavirus disease. They were developed to mimic the immunity following natural rotavirus infection that confers protection against severe gastroenteritis and consequently reduces the risk of primary healthcare utilization, hospitalization and death. The two currently licensed vaccines--one a single human strain rotavirus vaccine, the other a multiple strain human-bovine pentavalent reassortant rotavirus vaccine--are administered to infants in a two- or three-dose course, respectively, with the first dose given at 6-14 weeks of age. In various settings they are safe, immunogenic and efficacious against many different rotavirus genotypes. In high and middle income countries, rotavirus vaccines confer 85-100% protection against severe disease, while in low income regions of Africa and Asia, protection is less, at 46-77%. Despite this reduced efficacy in low income countries, the high burden of diarrheal disease in these regions means that proportionately more severe cases are prevented by vaccination than elsewhere. Post-licensure effectiveness studies show that rotavirus vaccines not only reduce rotavirus activity in infancy but they also decrease rates of rotavirus diarrhea in older and unimmunized children. A successful rotavirus vaccination program will rely upon sustained vaccine efficacy against diverse and evolving rotavirus strains and efficient vaccine delivery systems. The potential introduction of rotavirus vaccines into the world's poorest countries with the greatest rates of rotavirus-related mortality is expected to be very cost effective, while rotavirus vaccines should also be cost effective by international standards when incorporated into developed countries immunization schedules. Nonetheless, cost effectiveness in each country still depends largely on the local rotavirus mortality rate and the price of the vaccine in relation to the per capita gross domestic product.
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Affiliation(s)
- Keith Grimwood
- Queensland Paediatric Infectious Diseases Laboratory, Queensland Children's Medical Research Institute, The University of Queensland, Royal Children's Hospital, Herston Road, Herston, QLD 4029, Australia.
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Cunliffe N, Wittel D, Ngwira B. History of rotavirus research in children in Malawi: the pursuit of a killer. Malawi Med J 2010; 21:113-5. [PMID: 20345020 DOI: 10.4314/mmj.v21i3.45631] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Rotavirus gastroenteritis is a major health problem among Malawian children. Studies spanning 20 years have described the importance, epidemiology and viral characteristics of rotavirus infections in the country. Despite a wide diversity of circulating rotavirus strains causing severe disease in young infants, a clinical trial of a human rotavirus vaccine clearly demonstrated the potential for rotavirus vaccination to greatly reduce the morbidity and mortality due to rotavirus diarrhoea in Malawi. This new enteric vaccine initiative represents a major opportunity to improve the health and survival of Malawian children.
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Affiliation(s)
- Nigel Cunliffe
- Division of Medical Microbiology, School of Infection and Host Defence, University of Liverpool, Duncan Building, Daulby Street, Liverpool L69 3GA, UK
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Full genomic analysis and possible origin of a porcine G12 rotavirus strain RU172. Virus Genes 2010; 40:382-8. [DOI: 10.1007/s11262-010-0454-y] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2009] [Accepted: 01/27/2010] [Indexed: 12/11/2022]
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Matthijnssens J, Bilcke J, Ciarlet M, Martella V, Bányai K, Rahman M, Zeller M, Beutels P, Van Damme P, Van Ranst M. Rotavirus disease and vaccination: impact on genotype diversity. Future Microbiol 2010; 4:1303-16. [PMID: 19995190 DOI: 10.2217/fmb.09.96] [Citation(s) in RCA: 267] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Temporal and spatial fluctuations in the genotype distribution of human rotaviruses are continuously observed in surveillance studies. New genotypes, such as G9 and G12, have emerged and spread worldwide in a very short time span. In addition, reassortment events have the potential to contribute substantially to genetic diversity among human and animal rotaviruses. With the recent introduction of the two rotavirus vaccines, RotaTeq and Rotarix, in many countries, it appears that the total number of hospitalizations due to rotavirus infections is being reduced, at least in developed countries that implemented a universal immunization program. However, continued surveillance is warranted, especially regarding the long-term effects of the vaccines. No data analyses are available to clarify whether rotavirus vaccine introduction would allow other rotavirus P and G genotypes, which are not covered by the current vaccines, to emerge into the human population and fill the apparent gap. This kind of data analysis is essential, but its interpretation is hampered by natural and cyclical genotype fluctuations.
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Affiliation(s)
- Jelle Matthijnssens
- Laboratory of Clinical and Epidemiological Virology, Department of Microbiology & Immunology, Rega Institute for Medical Research, University of Leuven, Leuven, Belgium.
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Madhi SA, Cunliffe NA, Steele D, Witte D, Kirsten M, Louw C, Ngwira B, Victor JC, Gillard PH, Cheuvart BB, Han HH, Neuzil KM. Effect of human rotavirus vaccine on severe diarrhea in African infants. N Engl J Med 2010; 362:289-98. [PMID: 20107214 DOI: 10.1056/nejmoa0904797] [Citation(s) in RCA: 696] [Impact Index Per Article: 46.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Rotavirus is the most common cause of severe gastroenteritis among young children worldwide. Data are needed to assess the efficacy of the rotavirus vaccine in African children. METHODS We conducted a randomized, placebo-controlled, multicenter trial in South Africa (3166 infants; 64.1% of the total) and Malawi (1773 infants; 35.9% of the total) to evaluate the efficacy of a live, oral rotavirus vaccine in preventing severe rotavirus gastroenteritis. Healthy infants were randomly assigned in a 1:1:1 ratio to receive two doses of vaccine (in addition to one dose of placebo) or three doses of vaccine--the pooled vaccine group--or three doses of placebo at 6, 10, and 14 weeks of age. Episodes of gastroenteritis caused by wild-type rotavirus during the first year of life were assessed through active follow-up surveillance and were graded with the use of the Vesikari scale. RESULTS A total of 4939 infants were enrolled and randomly assigned to one of the three groups; 1647 infants received two doses of the vaccine, 1651 infants received three doses of the vaccine, and 1641 received placebo. Of the 4417 infants included in the per-protocol efficacy analysis, severe rotavirus gastroenteritis occurred in 4.9% of the infants in the placebo group and in 1.9% of those in the pooled vaccine group (vaccine efficacy, 61.2%; 95% confidence interval, 44.0 to 73.2). Vaccine efficacy was lower in Malawi than in South Africa (49.4% vs. 76.9%); however, the number of episodes of severe rotavirus gastroenteritis that were prevented was greater in Malawi than in South Africa (6.7 vs. 4.2 cases prevented per 100 infants vaccinated per year). Efficacy against all-cause severe gastroenteritis was 30.2%. At least one serious adverse event was reported in 9.7% of the infants in the pooled vaccine group and in 11.5% of the infants in the placebo group. CONCLUSIONS Human rotavirus vaccine significantly reduced the incidence of severe rotavirus gastroenteritis among African infants during the first year of life. (ClinicalTrials.gov number, NCT00241644.)
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Affiliation(s)
- Shabir A Madhi
- Department of Science and Technology/National Research Foundation: Vaccine Preventable Diseases, University of the Witwatersrand, Johannesburg, South Africa
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A long-term survey on the distribution of the human rotavirus G type in Thailand. J Med Virol 2010; 82:157-63. [DOI: 10.1002/jmv.21596] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Abstract
PURPOSE OF REVIEW The authors discuss the most relevant information in the field of rotavirus vaccines published from October 2007 to June 2009; new information on the virus, host response and disease burden that relate to our understanding of vaccine mechanisms and impact are discussed. The review will focus on the role of the vaccines for the developing world but this does not preclude the relevance of these vaccines for children living in the industrialized world. RECENT FINDINGS Immune mechanisms involved in rotavirus-associated immunity potentially relevant for vaccine-associated immunity continue to be identified including anti-NSP4 antibodies, cellular and mucosal mechanisms. Rotavirus-associated disease burden is high, causing approximately 40% of diarrhea-associated hospitalizations in children less than 5 years of age worldwide; G12, G8 and P[6] antigenic types emerging in developing countries are increasing in prevalence and may share worldwide circulation with the other five more common serotypes. The two currently available vaccines, based on different immune concepts, (VP7/VP4 homotypic specificity for RotaTeq vs. homotypic and heterotypic specificity for Rotarix) have demonstrated high and sustained efficacy in middle and high-income countries. Recent efficacy and effectiveness studies demonstrate acceptable protection levels in the poorest countries of the world against most antigenic types, leading to universal vaccine recommendation. Postlicensure surveillance has not detected any signal of increased risk for intussusception in children vaccinated with any of the two vaccines. SUMMARY Rotavirus vaccines are well tolerated and provide adequate protection against moderate to severe disease in high, middle and low-income regions. Partnerships between governments, industry, and funding agencies will now be urgently needed to promote vaccine use, especially in the less privileged countries of the world.
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Abstract
PURPOSE OF REVIEW Acute gastroenteritis is one of the leading causes of morbidity and mortality in children in the developing world. With improvements in hygiene and sanitation, the burden of disease due to bacterial and parasitic infections has decreased and an increasing proportion of diarrhoea hospitalizations are attributed to viruses. This review focuses on enteric viruses and their role in childhood diarrhoea in the developing world. RECENT FINDINGS With the use of sensitive molecular techniques, it is evident that a significant proportion of childhood diarrhoea is attributable to enteric viruses, with at least one viral agent in nearly 43% of samples from childhood diarrhoea in developing countries. Rotaviruses remain the most common pathogens in children, followed by noroviruses in almost all countries. There is increasing evidence that both rotaviruses and caliciviruses spread beyond the gut in a large proportion of infections. SUMMARY The review highlights the importance of viral agents of gastroenteritis in developing countries. Wider use of molecular techniques is resulting in rapid identification of new or emerging strains and in the detection of extra-intestinal spread. There is a need to better understand susceptibility and immune response to these agents to be able to design suitable interventions.
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Sanchez-Padilla E, Grais RF, Guerin PJ, Steele AD, Burny ME, Luquero FJ. Burden of disease and circulating serotypes of rotavirus infection in sub-Saharan Africa: systematic review and meta-analysis. THE LANCET. INFECTIOUS DISEASES 2009; 9:567-76. [DOI: 10.1016/s1473-3099(09)70179-3] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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