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Reported COVID-19 Incidence in Wisconsin High School Athletes in Fall 2020
Phillip Sasser1, Timothy A McGuine2, Kristin Haraldsdottir2
1Department of Pediatrics, University of Wisconsin School of Medicine and Public Health, Madison.
Objective:
To describe the incidence of COVID-19 in Wisconsin high school athletes and investigate the relationship of COVID-19 incidence with sport and face mask use.
Design:
Retrospective survey.
Setting:
High schools across Wisconsin during September 2020.
Patients Or Other Participants:
Athletic directors representing 30 074 high school athletes with or without SARS-CoV-2.
Main Outcome Measurement(S):
The COVID-19 rates among athletes, counties, states, as well as school instruction type (virtual versus in person), sport type, and face mask use were assessed. Reported athlete case rates were compared with the county's general population and associations between COVID-19 incidence and sport type and face mask use, adjusting for each school's county incidence using multivariable negative binomial regression models.
Results:
The COVID-19 incidence rates for 207 of 244 responding schools were 32.6 cases per 100 000 player-days. Reported case rates for athletes in each county were positively correlated with the county's general population case rates (β = 1.14 ± 0.20, r = 0.60, P < .001). One case (0.5%) was attributed to sport contact by the reporting schools. No difference was identified between team and individual sports (incidence rate ratio [IRR] = 1.03 [95% CI = 0.49, 2.2], P = .93) or between noncontact and contact sports (IRR = 0.53 [0.23, 1.3], P = .14). Outdoor sports had a lower incidence rate than indoor sports, although this finding did not reach statistical significance (IRR = 0.52 [0.26, 1.1], P = .07). No significant associations were found between COVID-19 incidence and face mask use during play for those sports with greater than 50 schools reporting on face mask use (P values > .05).
Conclusions:
The incidence of reported COVID-19 among high school athletes was related to the county incidence, and most cases were attributed to nonsport contact. A lower COVID-19 incidence in outdoor sports approached statistical significance. The lack of a significant benefit demonstrated for face mask use may be due to relatively low rates of COVID-19 in Wisconsin during September 2020. Further research is needed to better define COVID-19 transmission risk factors during adolescent sport participation.
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