Catch-up polio immunization campaign to begin in Ukraine
cVDPV2 outbreak response continues in the country
A poliomyelitis (polio) vaccination campaign for children aged 6 months to 6 years who missed routine polio doses in the past will begin in Ukraine on 1 February 2022. This catch-up campaign is part of a comprehensive response to stop an outbreak of poliovirus first detected in Ukraine in October 2021. This first stage will last 3 weeks and is expected to reach nearly 140 000 children throughout the country.
Years of low immunization coverage in Ukraine have created a large pool of unvaccinated or under-vaccinated children who are vulnerable to polio. While routine immunization coverage has gradually increased over the past 6 years, in 2020, only 84% of 1-year-olds received the required 3 scheduled doses of polio vaccines by 12 months of age.
The immediate goal of the campaign is to reach the WHO-recommended level of 95% vaccination coverage of eligible children.
Background
The polio outbreak in Ukraine was confirmed on 6 October 2021. Poliovirus (circulating vaccine-derived poliovirus type 2) was first isolated in a 17-month-old girl in the province of Rivne who developed acute flaccid paralysis. Analysis of all her contacts found that 7 household contacts (siblings) and 8 community contacts in Rivne as well as 4 cousins in the province of Zakarpattya (who had had contact with the girl’s siblings) also tested positive, but did not develop paralytic symptoms.
A second case with acute flaccid paralysis (a 2-year-old boy in the region of Zakarpattya) also tested positive for poliovirus, with onset of paralysis in December 2021.
The isolated strain of the virus found in both paralytic cases and their contacts is linked to a poliovirus in Pakistan, which was also the cause of several cases in Tajikistan in 2020–2021.
Comprehensive plan to stop the spread of poliovirus
Following an initial local vaccination campaign, conducted where the first case was detected, a comprehensive polio outbreak response plan was approved by the Ministry of Health in December 2021.
The first stage of the plan will provide inactivated polio vaccine (IPV) to children aged 6 months to 6 years who have not received the required number of doses. In the second stage, all children under the age of 6 will be vaccinated with oral polio vaccine (OPV), even if they have received all their scheduled vaccination doses. This is necessary to protect children from infection and to stop the circulation of the virus. Dates for the second stage are pending.