http://www.npr.org/sections/health-shots/2016/11/22/503004023/infectious-diseases-keep-delivering-surprises-to-the-u-s?utm_campaign=KHN%3A+First+Edition&utm_source=hs_email&utm_medium=email&utm_content=38118653&_hsenc=p2ANqtz-_5lt711bnuqlazwV5ct-xcrJYo7Q1p8GiMl2X3dDaM1ncz_MiHQN1fx4nJ2W-d5VWPMxduzKAaWur38GtqvRqTX6ZvSw&_hsmi=38118653

Infectious diseases are no longer the major killers in the U.S. that they once were, but they still surprise us.

According to a report published Tuesday in JAMA, the journal of the American Medical Association, deaths from infectious disease accounted for 5.4 percent of deaths from 1980 to 2014.

That’s a big change from 1900, when infectious diseases like pneumonia, tuberculosis and diarrhea accounted for almost half of all deaths. The historical decline represents great progress in sanitation, antibiotic discovery and vaccination programs, says Heidi Brown, an assistant professor of public health at the University of Arizona and an author of the research letter. “We’ve done phenomenal and amazing things with respect to infectious diseases,” she says.

But if you dig into the data a bit, she says, you can see where new diseases make an appearance, sometimes a deadly and dramatic one. For example, between 1980 and 1995, the number of deaths per 100,000 people from HIV/AIDS rose by an average of more than 85 percent per year. Then when new antiretroviral drugs became available, that rate fell by an average of more than 10 percent annually from 1995 to 2014.

“We went from not understanding [the disease] to being able to do something about it in a relatively short period of time,” says Brown. (To be sure, even with the gains we’ve made, the epidemic is not over.)