title: G8 rotaviruses with conserved genotype constellations detected in Malawi over 10 years (1997-2007) display frequent gene reassortment among strains co-circulating in humans.
abstract: Rotavirus A, the most common cause of severe diarrhoea in children worldwide, occurs in five major VP7 (G) and VP4 (P) genotype combinations, comprising G1P[8], G2P[4], G3P[8], G4P[8] and G9P[8]. However, G8, a common bovine rotavirus genotype, has been reported frequently among children in African countries. Surveillance of rotavirus gastroenteritis conducted in a sentinel hospital in Blantyre, Malawi between 1997 and 2007 provided a rare opportunity to examine the whole genotype constellation of G8 strains and their evolution over time. A sample of 27 (9.0 %) of 299 G8 strains was selected to represent each surveillance year and a range of P genotypes, which shifted in predominance from P[6] to P[4] and P[8] during the study period. Following cell culture adaptation, whole genome sequencing demonstrated that the genetic background of 26 strains possessed the DS-1 genotype constellation. A single G8P[6] strain was a reassortant in which both NSP2 and NSP5 genes from strains with the Wa genotype constellation had been inserted into a strain with the DS-1 genotype background. Phylogenetic analysis suggested frequent reassortment among co-circulating strains with the DS-1 genotype constellation. Little evidence was identified to suggest the introduction of contemporary bovine rotavirus genes into any of the 27 G8 strains examined. In conclusion, Malawian G8 strains are closely related to other human strains with the DS-1 genotype constellation. They have evolved over the last decade through genetic reassortment with other human rotaviruses, changing their VP4 genotypes while maintaining a conserved genotype constellation for the remaining structural and non-structural proteins.
authors: Department of Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, Faculty of Health and Life Sciences, University of Liverpool, Liverpool, UK.|Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, and the Global Centre of Excellence, Nagasaki University, Nagasaki, Japan.
authors: Toyoko
authors: T
authors: Nakagomi
authors: Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, and the Global Centre of Excellence, Nagasaki University, Nagasaki, Japan.
authors: Yen Hai
authors: YH
authors: Doan
authors: Department of Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, Faculty of Health and Life Sciences, University of Liverpool, Liverpool, UK.
authors: Winifred
authors: W
authors: Dove
authors: College of Medicine, University of Malawi, Blantyre, Malawi.
authors: Bagrey
authors: B
authors: Ngwira
authors: Department of Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, Faculty of Health and Life Sciences, University of Liverpool, Liverpool, UK.
authors: Miren
authors: M
authors: Iturriza-Gómara
authors: Department of Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, Faculty of Health and Life Sciences, University of Liverpool, Liverpool, UK.|Department of Molecular Microbiology and Immunology, Graduate School of Biomedical Sciences, and the Global Centre of Excellence, Nagasaki University, Nagasaki, Japan.
authors: Osamu
authors: O
authors: Nakagomi
authors: Department of Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, Faculty of Health and Life Sciences, University of Liverpool, Liverpool, UK.
authors: Nigel A
authors: NA
authors: Cunliffe
mesh_terms: D000818:Animals; D000866:Antelopes; D002417:Cattle; D002418:Cattle Diseases / Q000821:virology*; D005759:Gastroenteritis / Q000453:epidemiology / Q000821:virology*; D005838:Genotype; D015511:Goat Diseases / Q000821:virology*; D006041:Goats; D006801:Humans; D008295:Malawi / Q000453:epidemiology; D008969:Molecular Sequence Data; D010802:Phylogeny; D011995:Recombination, Genetic; D012401:Rotavirus / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification*; D012400:Rotavirus Infections / Q000453:epidemiology / Q000662:veterinary* / Q000821:virology*; D012756:Sheep; D012757:Sheep Diseases / Q000821:virology*