The World Health Organization (WHO) said it will conduct another mass vaccination round in the Gaza Strip to protect children against polio.
The campaign, led by the Palestinian Ministry of Health with support from the WHO, the United Nations Children's Fund (UNICEF), and other partners, will target 591,000 children under ten years of age who are at risk of poliovirus infection. A further vaccination round has already been planned for April.
Polio cases have been reduced by 99.9% due to vaccines but rare strains are still present in communities with low vaccination rates. Variant type 2 poliovirus, a strain originating from the live virus contained in the oral polio vaccine that circulates in under-immunised populations, was found in sewage samples in the Gaza Strip in July 2024.
The WHO said that overcrowding in shelters and severely damaged water infrastructure arising from the Israeli-Hamas conflict have led to conditions that increase faecal-oral transmission of the virus.
Polio is a highly infectious viral disease that largely affects children under five years of age, spread mainly through the faecal-oral route. It invades the nervous system and can cause paralysis in the legs and respiratory muscles.
The WHO and its partners have already conducted two vaccination rounds to combat polio in the region in September and October 2024. The vaccination schedule reached over 95% of its target population, with the hostilities forcing some children to evacuate to Gaza City where health workers were based, improving vaccine access. Still, certain areas remained "inaccessible" due to the conflict, which meant around 7,000 children missed vaccination during the second round.
Polio is still being identified in Gaza and the neighbouring region, meaning children with low or no immunity are still at risk of infection. No new cases have been reported since August 2024 when a ten-year-old child was left paralysed due to the disease. Though WHO reported that new samples from two cities in central and southern Gaza, collected in December 2024 and January 2025, confirm poliovirus transmission.
A ceasefire to the conflict was announced on 15 January 2025, bringing respite to channels of humanitarian aid that were under strain. The WHO confirmed that "health workers have considerably better access now" because of the suspension in fighting. Transmission, however, is likely to worsen as people move between regions.
"Extensive population movement consequent to the current ceasefire is likely to exacerbate the spread of poliovirus infection," WHO said in a statement.