Australian Rotavirus Surveillance Program annual report, 2014

The Australian Rotavirus Surveillance Program, together with collaborating laboratories Australia-wide, reports the rotavirus genotypes responsible for the hospitalisation of children with acute gastroenteritis. During the survey period of 1 January to 31 December 2014, 1,022 faecal samples were referred for rotavirus G and P genotype analysis, and of these 733 were confirmed as rotavirus positive. A total of 480 specimens were collected from children under 5 years of age, while 253 were from older children and adults. Genotype analysis of the 733 rotavirus samples collected from both children and adults revealed that G12P[8] was the dominant genotype in this reporting period, identified in 29.6% of strains nationally. Genotype G1P[8] was the 2nd most common strain nationally, representing 22.9% of samples, followed by genotype G3P[8] (14.9%). This report highlights the continued significance of G12P[8] strains as the major cause of disease in this population. The genotype distribution was slightly altered when the analysis was restricted to samples collected from children under 5 years of age, with G1P[8] being the dominant genotype (29%) followed by G12P[8] as the 2nd most common genotype (26%). Fluctuations in genotype distribution were also observed based on the vaccine type in use. Genotype G12P[8] was more common in states and territories using RotaTeq, while G1P[8] was more common in the locations using Rotarix. This survey highlights the yearly fluctuations in rotavirus genotypes observed since vaccine introduction. The continuation of G12P[8] as the dominant genotype further illustrates the dynamic and diversity present in the wild-type rotavirus population evident in the Australian population since vaccine introduction.