Despite Reductions in Infectious Disease Mortality in U.S., Diarrheal Disease Deaths on the Rise

Deaths from infectious diseases have declined overall in the United States over the past three decades. However, the rates of decline varied significantly by counties, according to a new scientific study. The number of deaths attributed to diarrheal diseases has increased substantially as well. While that number is relatively small (about 8,000), diarrhea-related deaths increased in nearly all counties from 1980 to 2014 and were ranked the second-leading cause of all infectious disease mortality behind lower respiratory infections (LRIs) such as pneumonia and bronchitis.

The full study, published today in JAMA, can be found here: http://jamanetwork.com/journals/jama/fullarticle/10.1001/jama.2018.2089

More detailed study findings are available in interactive data visualization tools at https://vizhub.healthdata.org/subnational/usa

LRI-related deaths accounted for more than three-quarters of all infectious disease deaths in 2014. A substantial proportion of those is likely due to the effects of an aging population.

"Our findings are relevant in examining local differences, which often are masked by national or state-level averages," said Dr. Charbel El Bcheraoui, lead author on the study and assistant professor at the Institute for Health Metrics and Evaluation (IHME) at the University of Washington. "These large disparities are due to variation in risk factors such as alcohol, drugs, or smoking, as well as socioeconomic factors and access to quality medical care. They underscore the need to monitor the transmission of infectious diseases carefully and to help prevent outbreaks."

Numerous countries within a corridor of states between Missouri and Maine were among the highest in the nation in 2014 for diarrhea-related deaths, with rates nearly 4 per 100,000 people.

Nationally, the death rate from infectious diseases decreased about 19 percent, from 42 to 34 deaths per 100,000 people, from 1980 to 2014.

Six major infectious disease groups were included in this analysis and each accounted for at least 1% of all deaths from infectious diseases nationally from 1980 to 2014. In addition to LRI, diarrheal diseases, and HIV/AIDS, these groups were hepatitis, meningitis, and tuberculosis. Deaths from chronic hepatitis B and chronic hepatitis C were excluded from the hepatitis grouping.

MORTALITY RATES PER 100,000 PEOPLE IN 2014
"Worst" county / "Best" county / US overall

Lower respiratory infections: East Feliciana Parish, LA (87.7) / Collier County, FL (7.2) / US (26.9)
Diarrheal diseases: Ross County, OH (6.1) / Kalawao County, HI, and Maui County, HI (both 0.5) / US (2.4)

HIV/AIDS: Union County, FL (54.9) / Saint Croix, WI (0.2) / US (2.4)

Meningitis: Oglala Lakota County, SD (1.2) / Marin County, CA (0.2) / US (0.4)

Hepatitis: Union County, FL (5.2) / Steel County, ND, and Waukesha County WI (both 0.1) / US (0.3)

Tuberculosis: Oglala Lakota County, SD (3.5) / Rich County, UT, and Hinsdale County, CO (both 0.1) / US (0.3)

Source: Institute for Health Metrics and Evaluation (IHME)