SARS-CoV-2 wastewater surveillance in a central Chinese metropolis: variant responses and correlation with clinical cases.
This study analyzed SARS-CoV-2 surveillance results in the urban wastewater of Zhengzhou, central China, to explore its association with community COVID-19 incidence and evaluate its early warning performance across different SARS-CoV-2 variant epidemic phases.
Weekly monitoring was conducted at five representative wastewater treatment plants from May 2024 to July 2025, yielding 325 samples. Viral loads of the ORF1ab and N genes were quantified using RT-qPCR, with statistical analyses performed included Spearman correlation, ANOVA, and cross-correlation function.
The two target genes showed high consistency and significant positive correlation with 14-day cumulative COVID-19 incidence. However, significant variant and marked heterogeneity was observed across variant periods and gene targets, with the N gene outperforming ORF1ab in stability. Wastewater viral signals preceded clinical cases by one week.
These findings supported the application value of wastewater-based epidemiology in post-pandemic COVID-19 surveillance, indicate its potential early warning capacity, and reveal notable heterogeneity in surveillance performance across viral variants and target genes.
Weekly monitoring was conducted at five representative wastewater treatment plants from May 2024 to July 2025, yielding 325 samples. Viral loads of the ORF1ab and N genes were quantified using RT-qPCR, with statistical analyses performed included Spearman correlation, ANOVA, and cross-correlation function.
The two target genes showed high consistency and significant positive correlation with 14-day cumulative COVID-19 incidence. However, significant variant and marked heterogeneity was observed across variant periods and gene targets, with the N gene outperforming ORF1ab in stability. Wastewater viral signals preceded clinical cases by one week.
These findings supported the application value of wastewater-based epidemiology in post-pandemic COVID-19 surveillance, indicate its potential early warning capacity, and reveal notable heterogeneity in surveillance performance across viral variants and target genes.
Authors
Zhang Zhang, Zhang Zhang, Zhao Zhao, Ma Ma, Lv Lv, Ma Ma, Zhang Zhang, Han Han
View on Pubmed