At least 22 people in Syria - most of them children younger than 2 - may have contracted polio, the World Health Organization (WHO) reported.
If confirmed by laboratory tests, this would be the first polio outbreak in the region in 14 years.
Last week WHO received reports of a cluster of cases of sudden paralysis in Deir Al Zour province. Initial tests came back positive for polio in two of the 22 cases, the organization said in a statement. Results for the remaining cases are expected next week.
There is no cure for polio, and one in every 200 infections causes permanent paralysis. Through vaccination, the disease has been eradicated in most parts of the world except in three countries, Afghanistan, Nigeria and Pakistan.
About 500,000 children in Syria are now unvaccinated against polio. The country previously had a vaccination rate of 95 percent, UNICEF spokeswoman Marixie Mercado told news media today.
The Syrian health ministry launched a vaccination campaign on Thursday, according to news reports.