Sewage sampling has turned up circulating variant type 2 poliovirus (cVDPV2) in two sites in the Gaza Strip, though no related paralysis cases have been detected, the Global Polio Eradication Initiative (GPEI) said in a July 19 statement.
Genetic analysis suggests the viruses from the two locations are related to each other, and are closely related to the variant circulating in Egypt in the last half of 2023. GPEI said the virus could have been introduced to Gaza as early as September 2023.
The health ministry is conducting a risk assessment to assess how well the surveillance system is doing at detecting acute flaccid paralysis and wastewater sampling and to more clearly assess subnational immunity levels.
"The ongoing crisis continues to pose a significant challenge to the ability to implement full disease surveillance and outreach with immunization services," the group said, adding routine immunization rates in the occupied Palestinian territory were optimal before the conflict began in 2023. Polio vaccine coverage was estimated to be 99% in 2022, declining to 89% in 2023, according to the latest estimates from global health groups.
GPEI said only 16 of 36 hospitals are partly functional and only 45 of 105 primary health facilities are operational. "The impact on health system, insecurity, inaccessibility, population displacement, and shortages of medical supplies, coupled with poor quality of water and weakened sanitation, have contributed to reduced routine immunization rates and an increased risk of vaccine-preventable diseases, including polio, the group said.
The World Health Organization considers the risk of further spread within Gaza as high.