Wastewater surveillance pilot at US military installations: a cost model analysis

Abstract

BackgroundThe coronavirus disease 2019 (COVID-19) pandemic highlighted the need for pathogen surveillance systems to augment both early warning and outbreak monitoring/control efforts. Wastewater samples provide a rapid and accurate source of environmental surveillance data to complement direct patient sampling. Due to its global presence and critical missions, the US military is a leader in global pandemic preparedness efforts. Clinical testing for COVID-19 on US Air Force (USAF) bases (AFBs) was effective, but costly with respect to direct costs and indirect costs of lost time. To remain operating at peak capacity such bases sought a more passive surveillance option and piloted wastewater surveillance (WWS) at 17 AFBs to demonstrate feasibility, safety, and utility from May 2021 to January 2022.ObjectiveHere we model the costs of a wastewater program for pathogens of pandemic potential within the specific context of US military installations using assumptions based on the results of the USAF and Joint Program Executive Office for Chemical, Biological, Radiological and Nuclear Defense (JPEO-CBRND) pilot program. The objective was to determine the cost of deploying WWS to all AFBs, relative to clinical swab testing surveillance regimes.MethodsA simple WWS cost projection model was built based on subject matter expert input and actual costs incurred during a WWS pilot program at USAF AFBs. Several SARS-CoV-2 circulation scenarios were considered and costs of both WWS and clinical swab testing were projected. Break even analysis was conducted to determine how reduction in swab testing could open up space to enable WWS to occur in complement.ResultsOur model confirms that wastewater surveillance is complementary and highly cost-effective when compared to existing alternative forms of biosurveillance. We find that the cost of WWS was between $10.5 - $18.5 million less expensive annually in direct costs as compared to clinical swab testing surveillance. When indirect cost of lost work is incorporated, including assumed lost work required to go obtain a clinical swab test, we estimate that over two thirds of clinical swab testing could be maintained with no additional costs upon implementation of WWS.ConclusionsOur results support adoption of wastewater surveillance across US military installations as part of a more comprehensive and early warning system that will enable adaptive monitoring during disease outbreaks.