Following the November identification of vaccine-derived poliovirus type 2 (VDPV2) in an Indonesian boy who developed acute flaccid paralysis (AFP), investigators also found the virus in three healthy children, the World Health Organization (WHO) said yesterday.
In an update, the WHO said genetic sequencing tests on samples from the patient and three healthy children have now confirmed transmission, meeting the criteria needed for the event to be classified as a circulating vaccine-derived poliovirus type 2 (cVDPV2) outbreak.
The three children aren't close contacts with the original patient, were from the same community in Aceh province, and are all asymptomatic. The boy with AFP had not been vaccinated, had no travel history, and had not had contact with people who had traveled.
Indonesia's last polio flare-up was in 2019, when a circulating vaccine-derived poliovirus type 1 (cVDPV1) outbreak was reported in Papua province.
The WHO said Aceh province has very low polio vaccination coverage and that Indonesia's health ministry on Nov 28 launched an immunization campaign targeting 1.2 million children under age 13 years in the province. More campaigns are planned for other provinces in the first months of 2023.
Other countries are grappling with recent evidence of cVDPV2, including the United States, the United Kingdom, and Israel.