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Updated: Nov 24, 2025

Author Spotlight: Advancements in Multiplex Detection of Respiratory Viruses
Published on: November 10, 2023
COVID-19 infection among first responders in Broward County, Florida, March-April 2020
Jianli Niu1, Jose A Rodriguez2, Candice Sareli1
1Office of Human Research, Memorial Healthcare System, Hollywood, FL 33021, USA.
Background:
First responders (FRs) may have a significant risk of coronavirus 19 (COVID-19) infection than the general population due to job-related exposures. We aimed to determine the prevalence and exposure patterns of COVID-19 among FRs.
Methods:
Between March and April 2020, FRs in Broward County, Florida, were screened for COVID-19 infection by real-time reverse transcription polymerase chain reaction assay using nasopharyngeal swabs. Demographics and COVID-19 positive rate of the FRs were summarized.
Results:
A total of 3375 FRs were screened for COVID-19 infection. The median age of FRs tested was 42 years (IQR 33-52 years), and 1464 (43.4%) were men. A total of 2902 (85.9%) were asymptomatic, and 473 (14.1%) reported symptoms associated with COVID-19. Overall, 289 (8.6%) were positive, with the highest rates among the age between 25 and 49 years. Of those testing positive, 235 (81.3%) were asymptomatic. Fourteen days after their first positive test, 81 (69.8%) of the 116 asymptomatically infected FRs were negative, and 35 (30.2%) remained positive and asymptomatic.
Conclusions:
The FRs in Broward County, FL, had an overall infection rate of 8.6% at the time of COVID-19 testing, and asymptomatic FRs accounted for 81.3% of infection. Active surveillance should be focused on the asymptomatic FRs with COVID-19.
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