The World Health Organization is warning of a rapid increase in measles cases around the world.
A WHO report released on Monday says that global measles cases in the first seven months of this year have increased nearly three times compared to the same period last year.
Preliminary data shows that more than 364,800 people in 182 nations were infected between January and July this year. The increase is conspicuous among countries where many people have never been vaccinated.
By region, cases in Africa rose by 900 percent, largely due to the continent's poor health care systems.
The western Pacific region, which includes east and southeast Asia, saw a 230 percent increase.
The United States had its largest number of measles cases in 25 years. Europe also recorded more cases than the previous year at nearly 90,000, despite comprehensive vaccination programs there.
The WHO says measles is spreading even in countries with a high vaccination rate, because people in certain regions or age groups have not been vaccinated.
The WHO says 95 percent of the population in any country or region must be vaccinated to prevent measles outbreaks. It's urging the world to enforce vaccination to prevent a further spread.