Rotavirus disease and genotype diversity in older children and adults in Australia.

BACKGROUND: Rotavirus is a major cause of gastroenteritis in children <5 years of age. The disease burden in older children, adults, and the elderly is underappreciated. This study describes rotavirus disease and genotypic diversity in the Australian population comprising children ≥5 years of age and adults. METHODS: Rotavirus positive faecal samples were collected from laboratories Australia-wide participating in the Australian Rotavirus Surveillance Program between 2010 and 2018. Rotavirus samples were genotyped using a hemi-nested multiplex RT-PCR. Notification data from the National Notifiable Diseases Surveillance System was also analysed. RESULTS: Rotavirus disease was highest in children aged 5-9 years and adults ≥85 years. G2P[4] was the dominant genotype in the population ≥5 years of age. Genotype distribution fluctuated annually and genotypic diversity varied amongst different age groups. Geographical differences in genotype distribution were observed based on the rotavirus vaccine administered to infants