Norovirus and rotavirus in children hospitalised with diarrhoea after rotavirus vaccine introduction in Burkina Faso.

Several studies report norovirus as the new leading cause of severe gastroenteritis in children after the global introduction of rotavirus vaccines. Burkina Faso introduced general rotavirus vaccination with the oral pentavalent vaccine RotaTeq in November 2013 and quickly reached a vaccine coverage of >90%. This study describes detection rates, clinical profiles and the molecular epidemiology of norovirus and rotavirus infections in 146 children aged <5 years with severe acute gastroenteritis in Ouagadougou, consecutively enrolled from a hospital between January 2015 and December 2015. Virus detection was performed with an antigen test or real-time polymerase chain reaction (PCR) and genotyping was performed by nucleotide sequencing or multiplex PCR. Rotavirus was found in 14% and norovirus in 20% of faecal samples. Norovirus infection was significantly more associated with severe dehydration compared to rotavirus (P < 0.001). Among genotyped norovirus samples 48% (12/25) belonged to GII.4 which caused significantly more diarrhoeal episodes than non-GII.4 genotypes (P = 0.01). The most common rotavirus genotypes were G2P[4] (30%), G12P[6] (25%) and G12P[8] (20%). Fifty percent of the rotavirus positive children were infected with fully or partly heterotypic strains. In conclusion, this study found a higher proportion of norovirus causing more severe symptoms in children with diarrhoea in Burkina Faso after the introduction of rotavirus vaccination.