Investigators search Gaza for cases of polio after virus found in wastewater

Polio has been detected in wastewater samples from Gaza, raising concerns among health officials as the territory has been polio-free for over 25 years. The World Health Organization (WHO) has initiated an investigation to identify any active cases, as experts suspect the virus may be circulating silently among the population. Investigators are collecting stool samples and reviewing medical records for signs of paralysis, a severe symptom of polio. Although no active cases have been confirmed yet, the presence of the virus in sewage suggests it may be spreading.

Genomic sequencing by the U.S. Centers for Disease Control and Prevention (CDC) linked the strain found in Gaza to one circulating in Egypt, indicating it may have entered Gaza as early as September 2023. The ongoing conflict has disrupted vaccination efforts and sanitation, creating conditions conducive to a polio outbreak. The detected strain is vaccine-derived, which can occur when the weakened virus from the oral polio vaccine mutates and infects unvaccinated individuals.

Health officials are working to identify at-risk populations and re-educate healthcare providers about polio symptoms and testing procedures. Vaccination coverage in Gaza has dropped from over 95% to an estimated 89%, with many children potentially unreachable due to the ongoing conflict. A mass vaccination campaign may be necessary, but implementing it in an active war zone poses significant challenges.