PV1

…distinguishable forms) of wild poliovirus: PV1, PV2, and PV3. The most widespread serotype is PV1. Both PV2 and PV3 have been eradicated.

…caused by a strain of PV1 that was very closely related to a strain isolated in Uttar Pradesh, India. Later that year the virus appeared in Kunduz province in northeastern Afghanistan, which shared a border with Tajikistan. Both Tajikistan and Kunduz province had been polio-free for more than a decade…