Wastewater Surveillance for Poliovirus in Selected Jurisdictions, United States, 2022-2023

Abstract

Wastewater testing can inform public health action as a component of polio outbreak response. During 2022-2023, a total of 7 US jurisdictions (5 states and 2 cities) participated in prospective or retrospective testing of wastewater for poliovirus after a paralytic polio case was identified in New York state. Two distinct vaccine-derived poliovirus type 2 viruses were detected in wastewater from New York state and New York City during 2022, representing 2 separate importation events. Of those viruses, 1 resulted in persistent community transmission in multiple New York counties and 1 paralytic case. No poliovirus was detected in the other participating jurisdictions (Connecticut, New Jersey, Michigan, and Illinois and Chicago, IL). The value of routine wastewater surveillance for poliovirus apart from an outbreak is unclear. However, these results highlight the ongoing risk for poliovirus importations into the United States and the need to identify undervaccinated communities and increase vaccination coverage to prevent paralytic polio.

Keywords: United States; environmental surveillance; poliovirus; viruses; wastewater surveillance; wastewater-based epidemiological monitoring.

Figure 1

Positive and negative poliovirus results by MMWR week by county and jurisdiction in wastewater surveillance for poliovirus, United States, March 5, 2022–December 31, 2023. Colored squares represent poliovirus results for >1 wastewater samples collected during an MMWR week, including results from prospective testing (New York state, New York City, Chicago, Michigan) and retrospective testing of archived samples (New York state, New York City, Illinois, New Jersey, Connecticut). Any week with a positive poliovirus result is colored red, green, or blue, depending on genetic linkage to the case. Indeterminate results are not included in this figure. For context, the paralytic case was confirmed July 21, 2022 (MMWR week 29), with onset in June 2022. MMWR, Morbidity and Mortality Weekly Report.

Figure 2

Total number of samples tested per county in participating jurisdictions in wastewater surveillance for poliovirus, United States, March 5, 2022–December 31, 2023. This figure represents the number of samples per county in participating jurisdictions on a logarithmic scale. A) Illinois, including the city of Chicago, and Michigan; B) New York, including New York City; Connecticut; and New Jersey. The thicker black borders in panel B show counties that had a positive sample for poliovirus.