Budget impact of wastewater surveillance for COVID-19 in a large urban jail: an activity-based cost analysis.

Background: Correctional facilities were disproportionately affected by SARS-CoV-2 (COVID-19) outbreaks. Wastewater surveillance programs (WSP) may provide early warnings of the presence of COVID-19 and facilitate the timely implementation of infection mitigation, but their budgetary implications for correctional systems remain unclear. Methods: We conducted an activity-based costing analysis of a pilot WSP in a large urban jail. Costs borne by the jail were assessed and included start-up investments, implementation expenditures, and the costs of confirmatory polymerase chain reaction testing (PCR test). We developed budget impact scenarios based on the number of outflow points testing positive and the confirmatory testing required in the cellblocks linked to them. We also conducted a scenario analysis using rapid antigen tests in place of PCR tests. Results: Initial start-up costs totaled $29,471. Implementation costs for testing a single outflow point, linked to seven cellblocks, were $16,802, with PCR-testing accounting for 78% of expenditures. Implementation costs varied from $4,403 for zero positive outflow tests to $125,965 for eight positive outflow tests. Use of rapid antigen tests reduced costs significantly. Conclusion: Adoption of wastewater surveillance with confirmatory testing in correctional settings may entail substantial costs. The budget impact is likely to be highly sensitive to confirmatory test type, sewer configuration, and the specificity of the wastewater sample to a location. These findings underscore the need for correctional administrators to investigate feasibility and affordability when considering the use of WSP to help protect incarcerated populations from infectious disease threats.