Reported exposure trends among healthcare personnel COVID-19 cases, USA, March 2020-March 2021

Abstract

Background: Health care personnel (HCP) have experienced significant SARS-CoV-2 risk, but exposure settings among HCP COVID-19 cases are poorly characterized.

Methods: We assessed exposure settings among HCP COVID-19 cases in the United States from March 2020 to March 2021 with reported exposures (n = 83,775) using national COVID-19 surveillance data. Exposure setting and reported community incidence temporal trends were described using breakpoint estimation. Among cases identified before initiation of COVID-19 vaccination programs (n = 65,650), we used separate multivariable regression models to estimate adjusted prevalence ratios (aPR) for associations of community incidence with health care and household and/or community exposures.

Results: Health care exposures were the most reported (52.0%), followed by household (30.8%) and community exposures (25.6%). Health care exposures and community COVID-19 incidence showed similar temporal trends. In adjusted analyses, HCP cases were more likely to report health care exposures (aPR = 1.31; 95% CI:1.26-1.36) and less likely to report household and/or community exposures (aPR = 0.73; 95% CI:0.70-0.76) under the highest vs lowest community incidence levels.

Discussion: These findings highlight HCP exposure setting temporal trends and workplace exposure hazards under high community incidence. Findings also underscore the need for robust collection of work-related data in infectious disease surveillance.

Conclusions: Many reported HCP cases experienced occupational COVID-19 exposures, particularly during periods of higher community COVID-19 incidence.

Keywords: Healthcare workers; Public health surveillance; SARS-CoV-2; Workplace exposure.

Fig 1

Reported COVID-19 cases (A) and deaths (B) among United States health care personnel from March 1, 2020 to March 31, 2021. Cases and deaths are plotted by the earliest date associated with each case, including symptom onset, diagnosis, or case reporting dates.

Fig 2

Counts (A) and proportions (B) of reported COVID-19 cases among United States health care personnel who reported known COVID-19 exposure settings from March 1, 2020 to March 31, 2021 by exposure setting during contact with known or suspected COVID-19 cases during the 14 days before COVID-19 symptom onset or diagnosis. Reported exposure settings, including health care-associated, community, and household, are indicated by color.

Fig 3

Time series breakpoints within health care personnel (HCP) exposure setting and community COVID-19 incidence time series from March 14, 2020 to December 13, 2020. (A) 7-day moving mean of the proportion of HCP cases who reported known COVID-19 exposure settings reporting health care-associated exposures. Time series breakpoints identified via segmented linear regression are shown as solid vertical lines, with robust 95% confidence limits shown as dotted vertical lines. (B) Median community COVID-19 incidence in HCP cases’ communities, defined as the 14-day cumulative count of COVID-19 cases per 100,000 county population.