PESHAWAR: The World Health Organisation is arranging vaccine for anti-polio campaigns in districts of Khyber Pakhtunkhwa, where six vaccine-derived poliovirus type 2 (VDPV2) cases were reported last week.

The VDPV2 was eradicated in 1999 leading to the withdrawal of the P2 vaccine from the worldwide anti-polio programme by the WHO in 2016.

However, after the re-emergence of the virus, the government has placed a request to the WHO for supplies on an urgent basis.

“To scale up the children’s immunity in seven districts, we have planned the case response campaign from Jan 27 to be followed by another drive in March. There are plans for national immunisation day in April,” coordinator for the National Emergency Operations Centre Dr Mohammad Rana Safdar told Dawn.

According to him, the centre successfully presented a demand to the WHO for securing P2 vaccine for all at-risk districts of Khyber Pakhtunkhwa.

Vaccination drives planned for this month, March and April, says official

Dr Safdar said the drive would target 1.9 million children under five years of age.

He said two more rounds would be conducted across 16 districts targeting 3.5m children in each of them during the Feb-April NIDs.

“The demand is based on detections and we have already responded toP2 cases in Diamer and Gujranwala,” he said.

Dr Safdar said the P2 vaccine was only issued by the WHO from global strategic stockpile on the recommendation of an advisorygroup, while the countries facing an outbreak made a case, which was reviewed and recommendations were made for the release of vaccine.

He said the IPV was available but it wasn’t effective to interrupt outbreaks as it didn’t enhance the gut immunity leaving child capable of transmitting the virus.

“However, one dose of IPV in routine immunisation helps protect the vaccinated children and therefore, it is good for preventing outbreaks,” he said.

The coordinator said the centre intended to stay ahead and would like to aggressively mitigate the VDPV risk as soon as possible to continue with intense focus on polio eradication.

He said the simultaneous efforts were under way in extensive outreach to quickly enhance the routine immunisation coverage to help tackle polio and other vaccine-preventable diseases.

According to experts, poliomyelitis has three strains, including 1, 2 and 3.

They said after P2 was eliminated, the use of Top (trivalent oral polio vaccine), which contained all three strains immunity, began. However, that vaccine is obsolete now.

The experts said when vaccine-derived P2 was procured for Gilgit-Baltistan and then Kohistan in last Oct, the case responses against the virus were carried in the districts, where outbreaks were reported.

They said until now, 18 P2 cases had been reported, including 12 in Khyber Pakhtunkhwa, so the authorities were in process of arranging vaccines to strengthen the children’s immunity.

The experts said the P2 vaccine wasn’t available readily due to which it was being arranged from the WHO for the children of at-risk districts.

They said malnourishment and unhygienic environment are said to be the basic reasons for re-emergence of P2 virus.

The experts said the VDPV2 cases reached to 18 as 12 cases were reported from Khyber Pakhtunkhwa, which is grappling with the outbreak of P1 virus that has so far infected 91 children in the province.

They, however, said the type 2 vaccine was removed from vaccination programme three years ago, then how the new vaccine derived cases are occurring.

Published in Dawn, January 19th, 2020