Long term assessment of SARS-CoV-2 in wastewater and the transition to evaluate additional viral targets

The COVID-19 pandemic caused by the SARS-CoV-2 virus dramatically impacted society over five years ago and continues to have an impact today. Since the beginning of the pandemic there have responses and strategies implemented to maintain the public safety of communities affected by SARS-CoV-2. This study is a unique opportunity to analyze nearly four years of SARS-CoV-2 wastewater-based surveillance (WBS) data, obtained from five different laboratories, combined with four years of human health data from three adjacent regions of a large urban community (Miami-Dade County). The objective of this study was to analyze that data and evaluate longitudinal and geographic trends of SARS-CoV-2 levels in wastewater (WW) during the extensive time frame of this study. Additionally, WBS data were analyzed for multiple targets (influenza A/B, norovirus, RSV, HMPV, PMMoV) other than SARS-CoV-2 to assess the potential for expanding WBS to a wider range of targets. We found that SARS-CoV-2 levels correlated strongest with clinical positivity rates across all three geographic regions (Spearman r = 0.81 for the entire period of record), with the most geographically restricted region showing higher correlations (South, r = 0.86) than the region with populations with higher geographic mobility (North, r = 0.69). Stronger correlations (0.80 < r < 0.97) were observed when correlations were established by variant waves rather than single or multiple year time frames (0.73 < r < 0.88). When analyzing the data for targets beyond SARS-CoV-2, results show promise as two laboratories detected norovirus, influenza A/B, RSV, and HMPV at statistically not different frequencies (Chi-squared≥0.6). Overall, results suggest that the clinical metrics used (e.g., positivity), geography, and the time frames of data analyses influence the ability of WBS to predict disease prevalence in a community. The consistency among the laboratories supports that the measurement of a wider range of viral targets can be disaggregated among different laboratories providing flexibility for building national-level WBS programs.