Infectious diseases were responsible for 5.4 percent of deaths in the U.S. from 1980 through 2014, though the top-killing diseases changed throughout that 34-year span, according to research published in JAMA.
Researchers used ICD codes to pull infectious disease mortality data from the National Office of Vital Statistics from 1900 through 1967 and from the CDC WONDER database from 1968 through 2014.
Here are eight things to know about deaths in the U.S. from infectious diseases, pulled from their report.
1. From 1900 through 1950, infectious disease mortality in the U.S. generally declined, except for a spike in 1918, thanks to the Spanish flu. According to the CDC, the Spanish flu pandemic of 1918-19 killed anywhere between 50 million and 100 million people worldwide.
2. After 50 years of general decline, infectious disease mortality leveled off after 1950. Even though mortality from infectious disease has remained somewhat stable since then, some new and emerging infectious diseases created mortality spikes from 1980 through 2014.
3. For instance, infectious disease mortality per 100,000 people rose from 42 in 1980 to 63.5 in 1995 because of the spread of HIV/AIDS, according to the study. However, after antiretroviral therapy was introduced, mortality again declined.
4. After West Nile virus was introduced in 2000 in the U.S., mortality due to vector-borne diseases increased from 0.01 per 100,000 people (from spotted fevers) to 0.05 per 100,000 population.
5. Hepatitis B mortality increased at a rate similar to that of HIV/AIDS in the 1980s and 1990s: In 1980, hepatitis B mortality was 0.13 per 100,000 people. In 1995, it grew to 0.39.
6. Clostridium difficile deaths used to almost be nonexistent — mortality was 0.004 per 100,000 in 1989. But C. diff mortality exploded since then, reaching a plateau of 2.4 per 100,000 in 2007.
7. Despite those emerging infectious diseases, influenza and pneumonia remain the deadliest infectious diseases in the U.S., according to the research. They accounted for roughly 40 percent of infectious disease mortality from 19890 through 2014.
8. "These trends illustrated the continued U.S. vulnerability to infectious diseases," the study concluded.