Epidemiological update: Detection of poliovirus in wastewater

On 23 December 2022, the Canada IHR National Focal Point reported a detection of a vaccine derived polio virus type 2 (VDPV2) in two wastewater samples collected in August 2022 from Canada. The United States’ CDC is examining the positive wastewater sample sequence data to assess any genetic linkages to VDPV2 samples collected from New York State. In light of this, the Pan American Health Organization/World Health Organization (PAHO/WHO) reiterates to Member States the need to have an updated response plan for polio outbreaks or events, join efforts to achieve vaccination coverage against poliomyelitis >95%, strengthen and maintain epidemiological surveillance of acute flaccid paralysis for the rapid detection of cases.