ISLAMABAD: Provincial polio programmes have finalised the arrangements to hold vaccination campaigns in selected districts of Sindh and Khyber Pakhtunkhwa from today (Monday).

Around four million children, up to five years of age, will be vaccinated during the campaign, Ministry of National Health Services (NHS) spokesperson Sajid Shah said while talking to Dawn.

He added that all arrangements for the campaigns have been made by the provinces.

`Around 369 union councils in 15 districts of KP and 119 UCs of nine districts of Sindh have been selected for the campaign,` Mr Shah told Dawn. `The target is over 2.1m children in KP and over 1.8m children in Sindh.

An official of the National Institute of Health (NIH), said the campaign has been planned after the polio virus was recently detected in a sewage sample from Karachi.

`Although we were getting positive environmental samples from some areas of KP, the virus in Karachi was detected for the first time in 10 months,` the official said, who wished to remain anonymous as they were not authorised to speak to the media.

The official added that the detection of virus in Karachi`s environmental sample has rung the alarm bell as it indicated the virus` resurgence.

Earlier this month, the national polio programme announced the detection of poliovirus in the envi-ronmental sample taken from the Sohrab Goth area of Karachi. The virus was detected in the city 11 months af ter a similar detection in August 2022 from Landhi.

The NIH official said if the polio virus was found in sewage water, the sample was called `positive`.

`Samples of sewage water from the area are a basic parameter to determine the success of polio campaigns. Moreover, the virus` presence in sewage also shows that the immunity level of children in the area has reduced and they are at risk of catching the disease,` he said.

`The Pakistan Polio Programme is already testing for poliovirus at 114 fixed environmental sites in the country every month.

To further enhance surveillance in high-risk areas, it has started collecting additional sewage samples from multiple sites periodically.

The virus detection in Karachi was not unexpected given the frequent population movement to the city from other areas.

Pakistan, one of the only two nations along with Afghanistan where polio is still present, has been striving to eradicate the virus. The country has seen success over the past few years.

However, recurring cases remain a challenge for the government.

After detecting no case for five months, the country reported its first polio case of 2023 in March after a three-year-old boy in KP`s Bannu district became the latest victim of the crippling disease.

KP, especially its southern region, comprising Dera Ismail Khan, Lalcki Marwat, Tank, Bannu, South Waziristan and North Waziristan, has been the epicentre of the virus in 2022, with all 20 cases being reported from districts in southern KP. Of them, 17 were from North Waziristan, two from Lakki Marwat and one from South Waziristan.