A-Z Index × Submit A-Z Index × Submit A-Z Index Search Dropdown × Submit Facebook Twitter LinkedIn Syndicate Emerging Infectious Disease journal ISSN: 1080-6059 Disclaimer: Early release articles are not considered as final versions. Any changes will be reflected in the online version in the month the article is officially released.
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We evaluated correlations between influenza A virus and respiratory syncytial virus (RSV) wastewater concentrations in California, USA, and 3 clinical laboratory–based disease surveillance datasets: sentinel laboratory surveillance, mandatory electronic laboratory reporting data, and laboratory-confirmed influenza hospitalizations. We evaluated data from 10 counties and 18 wastewater treatment plants in California during July 2022–March 2024. We observed strong, positive, and statistically significant correlations between individual sewershed-level wastewater concentrations and county-aggregated wastewater concentrations of influenza A and RSV and clinical laboratory–based surveillance datasets (median Kendall τ 0.62 [range 0.40–0.78]; p < 0.05). A lead–lag analysis did not show consistent evidence of wastewater leading other surveillance datasets across all counties and wastewater treatment plants (influenza A –16 to 22 days; RSV –8 to 35 days). Wastewater surveillance can augment other disease surveillance modalities and improve situational awareness of influenza A and RSV transmission in communities.
Influenza virus and respiratory syncytial virus (RSV) cause substantial illness and death in the United States ( 1 , 2 ). Public health agencies use influenza and RSV surveillance data to track annual seasonal patterns, known as respiratory virus seasons. That surveillance is used for hospital capacity planning, public and healthcare provider awareness, resource allocation, and planning for vaccinations and therapeutics. National influenza and RSV surveillance relies primarily on data from state, tribal, local, and territorial health departments. Those entities, in turn, rely on surveillance drawn from heterogenous data sources, including public health laboratories, clinical laboratories, vital statistics offices, health care providers, emergency departments, and long-term care facilities that variably contribute testing, genomic sequencing, and syndromic, hospitalization, and death data ( 3 ). Although effective, that surveillance approach has heterogenous coverage gaps and is subject to biases caused by disparate healthcare access and healthcare seeking behavior because persons with mildly symptomatic or asymptomatic infections might not seek clinical testing ( 4 ).
Wastewater surveillance (WS) could fill some of those gaps in surveillance by providing information about disease circulation in areas with limited testing and case reporting, warning of unexpected outbreaks, and helping public health practitioners determine when respiratory virus seasons begin and peak ( 5 ). WS has been used as a complementary tool alongside COVID-19 clinical surveillance to track trends in SARS-CoV-2 transmission, identify surges or outbreaks, and monitor virus variants ( 6 – 13 ). When evaluated alongside clinical surveillance data, wastewater data have provided a more complete picture of SARS-CoV-2 transmission in geographic areas with low testing or reporting rates. In addition, evidence suggests that WS might provide an early warning signal for the start of COVID-19 outb…