The World Health Organization (WHO) released the following summary on the polio situation in Pakistan earlier this week:

In Pakistan, a circulating vaccine-derived poliovirus type 2 (cVDPV2) has been detected from environmental samples in Quetta, Balochistan. Two isolates with apparent genetic linkages were isolated from environmental samples, collected on 20 October and 28 November 2016. Virus was isolated from environmental samples only and no associated cases of paralysis linked to the isolated strains have been detected in Quetta or anywhere else in the province.
Pakistan also continues to be affected by endemic transmission of wild poliovirus type 1 (WPV1). As of 21 December, 19 WPV1 cases have been reported in 2016. It is the lowest number of annual cases ever reported, from the fewest number of affected areas in the country.
The majority of the polio cases during the last six months were reported from non-reservoir areas, i.e. from ‘tier 2, 3 and 4’ districts (districts which are considered to be more vulnerable to polio re-infection). There have been no paralytic cases of wild poliovirus from the traditional polio reservoirs in Pakistan since February 2016.
A response with monovalent oral polio vaccine type 2 (mOPV2) in the Quetta and neighbouring districts is now planned, in line with internationally-agreed protocols. The first campaign of a series of campaigns is planned for 2 January 2017. In addition, the Ministry of National Health Services, Regulations and Coordination (MoHSRC), supported by World Health Organization (WHO), UNICEF and other partners, is further strengthening active search for cases of acute flaccid paralysis (AFP), and conducting an in-depth field investigation to more clearly ascertain the circulation of this strain. Pakistan continues to implement the National Emergency Action Plan for polio eradication, to urgently interrupt all remaining strains of polio transmission in the country.