Some 17 children have been paralyzed following an outbreak of polio in Syria, according to the World Health Organization (WHO).
Two cases of the disease were reported in Mayadin in Deir al-Zour in eastern Syria earlier this month. Since then, 14 new cases have been confirmed in the area with another case confirmed in Raqqa, an area controlled by Islamic State (IS, Formerly ISIS/ISIL).
WHO spokesman Tarik Jasarevic said the 17 children began showing symptoms as early as March 3 but tests only recently confirmed the presence of “vaccine-derived” polio.
This, Jasarevic said, indicates there was under-immunization in the Mayadin area.
WHO plans to vaccinate 90,000 children under five in the area, along with an additional 320,000 children in other parts of Deir al-Zour.
"We are very worried, because obviously if there is already one case of polio of a kid that is paralysed it's already an outbreak," he said. "We know, for example, that for one kid that is paralysed there are almost 200 asymptomatic. It means that virus is circulating. It is very serious."
There have been no reports of polio in Syria since 2014. According to WHO, Mayadin was also the outbreak epicentre in 2013.
Polio is a viral disease which largely affects children under five. The disease can cause paralysis in one in 200 cases, with up to 10 percent of those cases leading to death when the muscles prevent them from breathing.
Officials in Deir al-Zour confirmed the outbreak of the vaccine-derived poliovirus type 2 (cVDPV2), the WHO said last week.