Israel’s Health Ministry is warning of a potential measles outbreak among people who returned from the Ukrainian city of Uman after Rosh Hashana last week, Times of Israel reported.

The ministry says passengers traveling to Israel on three flights on September 12 were confirmed to have the measles, and warned that passengers on those flights were at risk of contracting the disease.

The statement said passengers on Ukrainian Airways flights PS101 and 779 and KLM flight 461 should see a doctor immediately.

The ministry said children, pregnant women and those suffering from auto-immune disorders were particularly susceptible to the disease.

Last month, the Health Ministry reported a massive increase in the number of reported cases of measles in Israel this year. It said 262 reported cases of the measles had been reported since the start of 2018, compared to only nine in all of 2016, and 33 cases in 2017.