| Title: |
Molecular epidemiology and evolution of norovirus in Australia and New Zealand, 2018 to 2020 |
| Authors: |
Joanne Hewitt; Grace J. H. Yan; Lewis K. Mercer; Emma F. Harding; Dawn Croucher; Alice G. Russo; Peter G. Huntington; Jason M. MacKenzie; William D. Rawlinson; Peter A. White |
| Publication Year: |
2025 |
| Collection: |
Erasmus University Rotterdam (EUR): Figshare |
| Subject Terms: |
Epidemiology not elsewhere classified; Wastewater surveillance; molecular epidemiology; Oceania; norovirus; SARS-CoV-2 |
| Description: |
Background: Norovirus causes an estimated 699 million cases of gastroenteritis and 219,000 deaths each year. Historically, novel strains with a genogroup II genotype 4 (GII.4) capsid have emerged every 3–5 years to cause gastroenteritis pandemics. Contrary to historical trends, viruses with aGII.4 Sydney 2012 capsid have extended the timeframe of capsid circulation, well beyond the usual 3–5 years, through genetic recombination to obtain new non-structural regions, for example, a GII.P16 ORF1. Objectives and methods: The molecular evolution in the GII.4 capsid of strains in New South Wales (NSW), Australia and New Zealand (NZ) before and into the COVID-19 pandemic (2018–20) was investigated by sequencing noroviruses from clinical specimens and wastewater. Results: A continued high prevalence of GII.4 Sydney 2012 [P16] was observed (NSW: 23.0%; NZ: 24.2%), albeit co-dominant with GII.2 [P16] (NSW: 20.2%; NZ: 29.4%). Unlike the historical trends, the GII.4 Sydney 2012 capsid has been in circulation for eight years. Circulating norovirus in the community was disrupted by COVID-19 control measures; lockdowns reduced viral concentration in wastewater by >90% (1.4 × 10 5 genome copies (gc)/L) from May to September 2020 compared to equivalent timeframes in 2018 (1.6 × 10 6 gc/L) and 2019 (1.9 × 10 6 gc/L). The relaxation of lockdown measures in late-2020 coincided with a strong resurgence of GII.2[P16] prevalence both clinically and in wastewater in NSW and Melbourne, accompanied by a decline in the diversity of circulating noroviruses. Conclusion: In summary, COVID-19 disrupted the strain diversity and levels of norovirus in Australia and New Zealand. |
| Document Type: |
article in journal/newspaper |
| Language: |
unknown |
| Relation: |
https://figshare.com/articles/journal_contribution/Molecular_epidemiology_and_evolution_of_norovirus_in_Australia_and_New_Zealand_2018_to_2020/29827088 |
| DOI: |
10.1080/23744235.2025.2479133 |
| Availability: |
https://doi.org/10.1080/23744235.2025.2479133; https://figshare.com/articles/journal_contribution/Molecular_epidemiology_and_evolution_of_norovirus_in_Australia_and_New_Zealand_2018_to_2020/29827088 |
| Rights: |
CC BY 4.0 |
| Accession Number: |
edsbas.A4FF75EB |
| Database: |
BASE |