Wastewater-Based Monitoring of Norovirus in Northern Region Malaysia

抄録

Norovirus (NoV) surveillance has been introduced as a national surveillance measure in many countries to monitor the epidemiology of NoV in a community. However, NoV surveillance in Malaysia is under-reported. This study was aimed to fill this research gap by capturing the prevalence of NoV GI and GII in Malaysia using wastewater-based monitoring. Monthly samples from three regional sewage treatment plants (RSTPs) located in Perak, Penang and Perlis were collected and processed from February 2023 to January 2024. NoV GI and GII were detected and quantified with real-time quantitative PCR. The seasonal distribution was analysed using rainfall data obtained from the Malaysian Meteorology Department. The results showed that NoV GI and GII were detected throughout the year at all RSTPs. NoV GII was identified as the predominant genogroup with detection rate of 94% out of total samples collected. The average viral loading per capita of each RSTP was estimated around 10⁶ genomic copies. Albeit no distinct seasonal correlation with rainfall was observed, two seasons of high viral load of total combined NoV GI and GII, were observed at all RSTPs. The two observed seasons; February–April 2023 and June–September 2023 coincided with the two inter-monsoon seasons in Malaysia.