Comparison of test specificities of commercial antigen-based assays and in-house PCR methods for detection of rotavirus in stool specimens

Seven commercial rotavirus antigen assays were compared with in-house PCR methods for detecting rotavirus in stool specimens. The assay sensitivities were 80% to 100%, while the specificities were 54.3% for one commercial immunochromatographic (ICT) method and 99.4% to 100% for other assays. Thus, except for one commercial ICT, all the assays were generally reliable for rotavirus detection

Evidence of false-positive results in a commercially available rotavirus assay in the vaccine era, Australia, 2011 to 2012

Concerns were raised about specificity of the VIKIA Rota-Adeno immunochromatographic kit. Only 28-37% of samples positive with the VIKIA kit could be confirmed using two real-time RT-PCR assays and three ELISA kits. On re-analysis of a subset of the positive samples, 86% remained positive with the VIKIA kit, however, 90% remained negative in the other assays. In a highly vaccinated population we found a high number of false-positive rotavirus tests with a widely-used commercial kit

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 <1 year of age. CONCLUSION: This study revealed a substantial burden of rotavirus disease in the population ≥5 years of age, particularly in children 5-9 years and the elderly. This study highlights the continued need for rotavirus surveillance across the population, despite the implementation of efficacious vaccines

Australian Rotavirus Surveillance Program: Annual Report, 2018.

Abstract: This report, from the Australian Rotavirus Surveillance Program and collaborating laboratories Australia-wide, describes the rotavirus genotypes identified in children and adults with acute gastroenteritis during the period 1 January to 31 December 2018. During this period, 690 faecal specimens were referred for rotavirus G- and P- genotype analysis, including 607 samples that were confirmed as rotavirus positive. Of these, 457/607 were wild-type rotavirus strains and 150/607 were identified as rotavirus vaccine-like. Genotype analysis of the 457 wild-type rotavirus samples from both children and adults demonstrated that G3P[8] was the dominant genotype nationally, identified in 52% of samples, followed by G2P[4] (17%). The Australian National Immunisation Program, which previously included both RotaTeq and Rotarix vaccines, changed to Rotarix exclusively on 1 July 2017. Continuous surveillance is needed to identify if the change in vaccination schedule could affect rotavirus genotype distribution and diversity in Australia

Australian Rotavirus Surveillance Program: Annual Report, 2019.

Abstract: This report, from the Australian Rotavirus Surveillance Program and collaborating laboratories Australia-wide, describes the rotavirus genotypes identified in children and adults with acute gastroenteritis during the period 1 January to 31 December 2019. During this period, 964 faecal specimens had been referred for rotavirus G- and P- genotype analysis, including 894 samples that were confirmed as rotavirus positive. Of these, 724/894 were wild-type rotavirus strains and 169/894 were identified as vaccine-like. A single sample could not be determined as wild-type or vaccine-like due to poor sequencing. Genotype analysis of the 724 wild-type rotavirus samples from both children and adults demonstrated that G3P[8] was the dominant genotype nationally, identified in 46.7% of samples, followed by G2P[4] in 8.8% of samples. The Australian National Immunisation Program (NIP) changed to the exclusive use of Rotarix as of 1 July 2017. The NIP had previously included two live-attenuated oral vaccines: Rotarix (monovalent, human) and RotaTeq (pentavalent, human-bovine reassortant) in a state-based vaccine selection. Continuous surveillance is imperative to determine the effect of this change in rotavirus vaccine schedule on the genotype distribution and diversity in Australia