The World Health Organization said on Tuesday that additional polio cases had been confirmed in two new areas of Syria, including near Damascus and in northern Aleppo, near Turkey, according to the agency's twitter account.
"In addition to 15 polio cases in Deir al-Zor province, Syria, two additional cases have been confirmed, one each in rural Damascus and Aleppo," the tweet said.
The incurable virus was confirmed this month in 13 children who became paralysed.
The WHO says polio is expected to spread after a drop in vaccination rates due to the war.
(Reporting by Oliver Holmes; Editing by Alison Williams)