Australian Rotavirus Surveillance Program: Annual Report, 2021

Area of Science:

• Virology
• Public Health
• Epidemiology

Background:

• Rotavirus is a leading cause of severe diarrheal disease in infants and young children globally.
• Rotavirus vaccines have been implemented worldwide, necessitating ongoing surveillance of circulating strains.
• The Australian Rotavirus Surveillance Program monitors rotavirus genotypes to understand epidemiology and vaccine effectiveness.

Purpose of the Study:

• To describe the rotavirus G- and P- genotypes circulating in Australia from January 1 to December 31, 2021.
• To identify wildtype, vaccine-like, and unusual rotavirus strains.
• To assess the impact of the COVID-19 pandemic on sample submission rates.

Main Methods:

• Analysis of 521 faecal specimens referred for rotavirus G- and P- genotype analysis.
• Confirmation of rotavirus positivity and subsequent genotyping of positive samples.
• Comparison of identified genotypes with known wildtype and vaccine strains.

Main Results:

• A total of 474 rotavirus-positive specimens were identified.
• Wildtype rotavirus strains accounted for 336/474 cases, with G8P[8] being the predominant genotype (87.5%).
• Unusual and potentially zoonotic genotypes, including feline, bovine-like, and porcine-like strains, were detected.

Conclusions:

• G8P[8] was the most prevalent wildtype rotavirus genotype in Australia during 2021.
• The detection of unusual zoonotic genotypes underscores the importance of continuous rotavirus surveillance.
• Surveillance provides crucial data for diagnostic laboratories and public health interventions.