In 2000, health officials announced that measles has been eliminated from the Americas, thanks to the measles vaccine and a strong vaccination program. (We still see some cases of measles, but they're imported. More on that below.) But as BBC News reports, the highly contagious disease is still on the rise in multiple European countries due to low immunization coverage. 

According to the World Health Organization (WHO), there were more than 500 reported measles cases in Europe in January 2017—and the number of new infections keeps on climbing. (To give this figure some perspective, there were 21 reported measles cases in the U.S. from January 1 to February 25, 2017.) The majority of these cases came from France, Germany, Italy, Poland, Romania, Switzerland, and Ukraine—all countries in which experts estimate that less than 95 percent of the population has received the second dose of the two-dose measles vaccine. Around 95 percent of people need to be vaccinated to protect the entire population from the disease.

Romania and Italy have been hit particularly hard. The former country has reported more than 3400 incidents of measles (and 17 deaths from the disease) since January 2016, according to the WHO. Meanwhile, Italy reported more than 200 cases for January of this year, and 850 total for 2016.

As for why vaccination coverage has waned across Europe, the reasons vary from country to country. Some nations, like Ukraine, have a hard time obtaining the measles vaccine and maintaining a high supply. In other places, like France, patients must book multiple doctor appointments to get both prescribed and vaccinated. And some people are simply afraid of getting shots, or don’t consider how important they are for the greater good.

People who contract measles experience a high fever, along with a cough, runny nose, watery red eyes, and a red rash that covers the entire body. It can be particularly dangerous, and even deadly, for seniors, children, or people weakened immune systems. As mentioned before, the disease is rare in the U.S.—but in recent years, our country has experienced a record number of measles cases, with 667 reported in 2014. (These numbers dipped to 188 in 2015, and to 70 in 2016.)

When a measles outbreak occurs in the U.S., it’s typically because a non-vaccinated individual visited another country, developed the disease, brought it home, and infected others who weren’t immunized. For example, in May 2014, Amish communities in Ohio reported 383 measles cases after several unvaccinated individuals brought the disease home from a missionary trip to the Philippines.

[h/t BBC News]