“At least two rounds of [orally delivered polio vaccine] It will be necessary to close the transmission”, The World Health Organization (WHO) and the United Nations Children's Fund (UNICEF) explained this in an update.
This development comes after the Global Polio Laboratory Network (GPLN) identified vaccine-derived poliovirus type 2 in wastewater samples collected on June 23 in Khan Younis and Deir al Balah on July 16.
Searching for the cause of paralysis
Health authorities in Gaza reported three cases of paralysis in late July and sent samples to Jordan for analysis. Acute flaccid paralysis can have numerous causes, including poliovirus, according to WHOwho stressed that the results for affected people in northern Gaza, Deir al Balah and Khan Younis have not yet been published.
The UN health agency previously noted that while Gaza had excellent polio vaccination coverage before the war, months of fighting have created the “perfect environment” for the weakened poliovirus vaccine to mutate into a stronger version capable of causing paralysis among those not fully immunized.
WHO and UNICEF also expressed concern about any delays in the delivery of polio vaccine and vital cold chain equipment amid intense fighting and insecurity in the enclave, and as regional tensions linked to the war in Gaza threaten further violence.
Appeal for help for humanitarian workers
“Humanitarian pauses are needed to vaccinate children and mitigate the risk of transmission”UN agencies insisted, after WHO Director-General Tedros Adhanom Ghebreyesus approved the release of 1.23 million doses of the new oral polio vaccine type 2 (nOPV2) for use in Gaza in an attempt to vaccinate more than 640,500 children under 10 years of age.
For the mass vaccination campaign to work, “safe and sustained access and the protection of health workers are required,” the UN agencies insisted, while noting that Only 16 of Gaza's 36 hospitals are “partially functional”.
Of the 107 primary health care centres, only 48 remain operational.
“The impact on the health system, insecurity, inaccessibility, population displacement and shortages of medical supplies have contributed to reduced immunization rates,” the agency’s update said. “Combined with poor water quality and the destruction of sanitation, there is an increased risk of vaccine-preventable diseases, including polio and other outbreaks.”
In Gaza, routine polio immunization coverage fell from 99% in 2022 to less than 90% in the first quarter of 2024, according to WHO and UNICEF.
