Polio remains a serious health threat in Pakistan. Caused by wild poliovirus type 1 (WPV1), this disease first emerged globally in 1916 and entered Pakistan in the 1970s. Despite efforts to eliminate polio, Pakistan remains one of only two countries, alongside Afghanistan, where the virus continues to circulate.
After a significant reduction in polio cases — from 147 in 2019 to just one in 2021 — Pakistan has seen a resurgence. Since September 2023, there has been an increase in polio activity, particularly in Karachi. In 2024, the country recorded 40 new cases, the highest in three years, with Balochistan being the most affected region. Environmental samples have consistently tested positive for WPV1, highlighting the risk to children, especially in areas with low routine immunisation coverage.
The main cause of the continued circulation of the polio virus in the environment is the lack of access to clean water, which increases the risk of transmission, particularly among unvaccinated or immunocompromised children. Alarmingly, over 70% of children affected by WPV1 had received the polio vaccine, but many had not completed the full immunisation regimen, especially the inactivated polio vaccine (IPV).
The barriers to polio eradication are multifaceted. Insecurity in areas like Balochistan and Khyber-Pakhtunkhwa limits vaccination efforts. Cultural and religious misconceptions also fuel vaccine hesitancy, although the majority of religious groups in Pakistan now endorse the polio vaccine. The virus spreads through contaminated water, and the country’s lack of clean drinking water is a major driver of continued transmission. It is the government’s responsibility to address this issue, as unclean water leads to waterborne diseases that contribute to high hospitalisation and death rates.
The solution to combating polio lies in a two-fold approach: comprehensive vaccination and robust surveillance. Every child must receive multiple doses of the polio vaccine to boost immunity, particularly in high-risk areas. Innovative methods such as the fractional dose IPV (fIPV) offer an efficient alternative, delivering two drops as effectively as a full dose. Environmental surveillance, through sewage testing, plays a critical role in detecting poliovirus and guiding vaccination efforts, complementing clinical surveillance of acute flaccid paralysis (AFP) for timely intervention.
Despite these challenges, the path forward is clear. Expanding access to healthcare, strengthening immunisation campaigns, and raising awareness in remote areas are crucial steps towards a polio-free Pakistan. Through collective action and persistent efforts, Pakistan can dispel the myths surrounding vaccination and protect future generations from this devastating disease.
Dr Ali Faisal Saleem
AKU, Karachi
