Measles is spreading across Europe wherever immunisation coverage has dropped, the World Health Organization is warning.
The largest outbreaks are being seen in Italy and Romania.
In the first month of this year, Italy reported more than 200 cases. Romania has reported more than 3,400 cases and 17 deaths since January 2016.
Measles is highly contagious. Travel patterns mean no person or country is beyond its reach, says the WHO.
For good protection, it’s recommended that at least 95% of the population is vaccinated against the disease.
But many countries are struggling to achieve that.
Most of the measles cases have been found in countries where immunisation has dipped below this threshold and the infection is endemic – France, Germany, Italy, Poland, Romania, Switzerland and Ukraine.
Preliminary information for February suggests that the number of new infections is rising sharply, says the WHO.
WHO regional director for Europe Dr Zsuzsanna Jakab said: “I urge all endemic countries to take urgent measures to stop transmission of measles within their borders, and all countries that have already achieved this to keep up their guard and sustain high immunisation coverage.”
The European Centre for Disease Prevention and Control says that between 1 February 2016 and 31 January 2017 the UK reported 575 cases of measles.