Four new cases of polio virus have been reported in northwest and southwest Pakistan, an official said on Monday.
With the new cases, the total number of polio-affected children rose to 41 in the current year.
"Today, four more polio cases, two each from Khyber Pakhtunkhwa (KP) and Balochistan provinces, were reported," Iftikhar Firdouse, director of communication for polio eradication program, told Anadolu Agency.
According to official data, 25 polio cases were reported from KP, three each from Punjab and Sindh province, two cases from Balochistan and eight cases were reported from tribal districts.
Polio virus still exists in Pakistan
Pakistan is among three countries in the world, including Afghanistan and Nigeria, where polio virus still exists and the country remains under a polio-linked travel restriction imposed by the World Health Organization (WHO).
In 2014, the WHO made it mandatory for all people travelling from Pakistan to carry a polio vaccination certificate.
Armed assailants belonging to militant groups have frequently targeted polio vaccinators and their security in several parts of Pakistan.
The groups see the anti-polio campaigns as part of an elaborate anti-Muslim and Western conspiracy, and often issue death threats to vaccinators, many of whom are women, for administering the vital vaccines to children.
According to Pakistani officials, around 88 people associated with the drive have been killed across Pakistan since December 2012.