Trends in U.S. Burden of Infection and Outcomes.

Background: Efforts to prevent infection continue to expand across the health care spectrum in the United States. Whether these efforts are reducing the national burden of infection is unclear.

Methods: The Emerging Infections Program identified cases of infection (stool specimens positive for in a person ≥1 year of age with no positive test in the previous 8 weeks) in 10 U.S. sites. We used case and census sampling weights to estimate the national burden of infection, first recurrences, hospitalizations, and in-hospital deaths from 2011 through 2017. Health care-associated infections were defined as those with onset in a health care facility or associated with recent admission to a health care facility; all others were classified as community-associated infections. For trend analyses, we used weighted random-intercept models with negative binomial distribution and logistic-regression models to adjust for the higher sensitivity of nucleic acid amplification tests (NAATs) as compared with other test types.

Results: The number of cases of infection in the 10 U.S. sites was 15,461 in 2011 (10,177 health care-associated and 5284 community-associated cases) and 15,512 in 2017 (7973 health care-associated and 7539 community-associated cases). The estimated national burden of infection was 476,400 cases (95% confidence interval [CI], 419,900 to 532,900) in 2011 and 462,100 cases (95% CI, 428,600 to 495,600) in 2017. With accounting for NAAT use, the adjusted estimate of the total burden of infection decreased by 24% (95% CI, 6 to 36) from 2011 through 2017; the adjusted estimate of the national burden of health care-associated infection decreased by 36% (95% CI, 24 to 54), whereas the adjusted estimate of the national burden of community-associated infection was unchanged. The adjusted estimate of the burden of hospitalizations for infection decreased by 24% (95% CI, 0 to 48), whereas the adjusted estimates of the burden of first recurrences and in-hospital deaths did not change significantly.

Conclusions: The estimated national burden of infection and associated hospitalizations decreased from 2011 through 2017, owing to a decline in health care-associated infections. (Funded by the Centers for Disease Control and Prevention.).