Prevalence and clinical profile of rotavirus A infection among diarrhoeal children and phylogenetic analysis with vaccine strains in Chengdu, West China, 2009-2014

ObjectivesRotaviruses are the most common cause of severe diarrhoeal disease in young children. However, little is known about the epidemiological and clinical profile of rotavirus A (RVA) in diarrhoeal children or the efficacy of Lanzhou lamb rotavirus vaccine (LLR) in Chengdu, China. This study aimed to determine the prevalence and clinical profile of RVA in diarrhoeal children and provide gene analysis information for RVA vaccination programmes. MethodsA total of 1121 faecal samples were collected from outpatient children with diarrhoea between 2009 and 2014. RT-PCR was performed to detect RVA infection and other gastroenteritis viruses. VP4 and VP7 genes of 13 RVA strains were sequenced to compare their similarity with vaccine strains. ResultsThe overall RVA infection rate was 17.48%. G1 (54.72%) and G3 (18.87%) were the predominant G genotypes; P[8] (72.36%) and P[4] (11.38%) were the main P genotypes. Sixteen genotypes were identified; G1P[8] (57.33%) and G9P[8] (12.00%) were the most prevalent. The proportion of coinfection with RVA and other gastroenteritis viruses was 18.88%. RVA was mostly detected in winter and in diarrhoeal children 1-2 years of age. The genotypes of Rotarix and RotaTeq vaccines were consistent with RVA strains prevalent in Sichuan and shared high identity. ConclusionsRVA was one of the major aetiological agents of diarrhoeal children in Chengdu. Genotype distribution differed within each year and the gene analysis implied low efficacy of LLR. Continuous epidemiological monitoring of RVA is essential for the national vaccination programme. ObjectifsLes rotavirus sont la cause la plus courante de maladie diarrheique severe chez les jeunes enfants. Cependant, on en sait peu sur le profil epidemiologique et clinique du rotavirus A (RVA) chez les enfants diarrheiques ou sur l'efficacite du vaccin Lanzhou lamb rotavirus (LLR) a Chengdu, en Chine. Cette etude visait a determiner la prevalence et le profil clinique du RVA chez les enfants diarrheiques et fournir des informations d'analyse genetique pour les programmes de vaccination RVA. Methodes1121 echantillons fecaux ont ete preleves chez des enfants ambulatoires souffrant de diarrhee entre 2009 et 2014. Une RT-PCR a ete realisee pour detecter l'infection a RVA et autres virus de la gastro-enterite. Les genes VP4 et VP7 de 13 souches RVA ont ete sequences pour comparer leur similarite avec les souches vaccinales. ResultatsLe taux global d'infection RVA etait de 17,48%. G1 (54,72%) et G3 (18,87%) etaient les genotypes G predominants; P[8] (72,36%) et P[4] (11,38%) etaient les principaux genotypes P. Au total 16 genotypes ont ete identifies; G1P[8] (57,33%), G9P[8] (12,00%) etaient les plus frequents. La proportion de coinfections entre RVA et d'autres virus de la gastroenterite etait de 18,88%. RVA a ete detectee principalement en hiver et chez les enfants diarrheiques de 1 a 2 ans. Les genotypes des vaccins Rotarix et RotaTeq etaient compatibles avec celles des souches RVA presentes dans le Sichuan, partageant une identite elevee. ConclusionsRVA etait l'un des principaux agents etiologiques des enfants diarrheiques a Chengdu. La distribution genotype differait au sein de chaque annee et l'analyse des genes suggerait une faible efficacite du LLR. Un suivi epidemiologique continu du RVA est essentiel pour le programme national de vaccination.