Status: circulating vaccine-derived poliovirus confirmed
A circulating vaccine-derived poliovirus type 2 (cVDPV2) has been confirmed in China. It is genetically linked to a VDPV2 isolated from an environmental sample from Xinjiang province, collected on 18 April 2018. WHO is continuing to evaluate the situation and stands ready to support the ongoing investigation and risk assessment by national authorities.
It is important that all countries, in particular those with frequent travel and contacts with polio-affected countries and areas, strengthen surveillance for AFP cases in order to rapidly detect any new virus importation and to facilitate a rapid response. Countries, territories and areas should also maintain uniformly high routine immunization coverage at the district level to minimize the consequences of any new virus introduction.
WHO’s International Travel and Health recommends that all travellers to polio-affected areas be fully vaccinated against polio. Residents (and visitors for more than 4 weeks) from infected areas should receive an additional dose of OPV or inactivated polio vaccine (IPV) within 4 weeks to 12 months of travel.