A routine environmental surveillance programme has detected two poliovirus strains in wastewater at a Cape Town treatment plant, prompting health authorities to strengthen monitoring measures while emphasising that no human cases have been identified.
Cape Town health authorities have intensified disease surveillance after the National Department of Health announced on Friday that two different poliovirus strains had been detected in wastewater sampled from a treatment plant in the city.
The detections were identified through routine environmental surveillance conducted by the National Institute for Communicable Diseases (NICD), which monitors wastewater and other water resources for signs of emerging diseases and viral variants before clinical cases appear.
According to the department, the strains detected were vaccine-derived poliovirus Type-3 (VDPV3) and novel oral poliovirus vaccine Type-2-like (nOPV2-L). However, health officials stressed that no human cases of polio have been identified and that the findings do not indicate an outbreak.
"These detections are called ‘vaccine events’ because no actual cases of the virus have been detected in a human being," the department said.
