Explained: Why has Pakistan’s vaccination programme come under scrutiny

Islamabad, Jun 25: Pakistan's vaccination programme has come under suspicion after the detection of poliovirus in sewage samples in London for the first time in four decades, according to a media report on Friday.

The UK Health Security Agency has noted that the virus detected on Thursday was probably imported from some country, and has asked parents to ensure their children were fully immunised against the crippling disease. Health authorities in Islamabad claim the "vaccine-derived virus" found in the UK exists in 22 countries and the type found locally was the wild poliovirus (WPV).

Pakistan Polio Eradication Programme National Coordinator Dr Shahzad Baig told the Dawn newspaper on Thursday that it was too early to say the virus had travelled from Pakistan, as UK authorities were yet to announce the results of genome sequencing.

Genome sequencing helps determine the origin of a virus, as samples detected in different areas have a different ribonucleic acid (RNA). A number of times, cases reported in Pakistan were reported to have originated from neighbouring Afghanistan during genome sequencing.

"We are waiting for the genetic sampling report of the virus. Moreover, there are two types of polioviruses in the world: WPV which is present in Pakistan and Afghanistan, and the vaccine-derived poliovirus (VDPV).

(PTI)