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Author Spotlight: Advancements in Multiplex Detection of Respiratory Viruses
Published on: November 10, 2023
SARS-CoV-2 infection among physicians over time in Ontario, Canada: a population-based retrospective cohort study
Steven Habbous1, Natasha Saunders, Kelvin Kw Chan
1Steven Habbous, 525 University Ave, Toronto, Ontario, Canada, M5G 2L3, steven.habbous@ontariohealth.ca.
Aim:
To assess this risk of SARS-CoV-2 infection among Ontario physicians by specialty and in comparison with non-physician controls during the COVID-19 pandemic.
Methods:
In this retrospective cohort study, the primary outcome was incident SARS-CoV-2 infection confirmed by polymerase chain reaction (PCR). Secondary outcomes were hospitalization, use of critical care, and mortality.
Results:
From March 1, 2020 to December 31, 2022, 6172/30 617 (20%) active Ontario physicians tested positive for SARS-CoV-2. Infection was less likely if physicians were older (OR 0.78 [0.76-0.81] per 10 years), rural residents (OR 0.70 [0.59-0.83]), and lived in more marginalized neighborhoods (OR 0.74 [0.62-0.89]), but more likely if they were female (OR 1.14 [1.07-1.22]), worked in long-term care settings (OR 1.16 [1.02-1.32]), had higher patient volumes (OR 2.05 [1.82-2.30] for highest vs lowest), and were pediatricians (OR 1.25 [1.09-1.44]). Compared with community-matched controls (n=29 763), physicians had a higher risk of infection during the first two waves of the pandemic (OR 1.38 [1.20-1.59]) but by wave 3 the risk was no longer significantly different (OR 0.93 [0.83-1.05]). Physicians were less likely to be hospitalized within 14 days of their first positive PCR test than non-physicians (P<0.0001), but there was no difference in the use of critical care (P=0.48) or mortality (P=0.15).
Conclusion:
Physicians had higher rates of infection than community-matched controls during the first two waves of the pandemic in Ontario, but not from wave 3 onward. Physicians practicing in long-term care facilities and pediatricians were more likely to test positive for SARS-CoV-2 than other physicians.
Insights
Ontario physicians faced higher COVID-19 infection risks than the general population during the pandemic's initial waves. Risk decreased over time, with long-term care physicians and pediatricians showing higher infection rates.
Area of Science:
- Epidemiology
- Infectious Diseases
- Public Health
Background:
- The COVID-19 pandemic posed significant risks to healthcare professionals.
- Understanding SARS-CoV-2 infection rates among physicians is crucial for occupational health strategies.
Purpose of the Study:
- To evaluate the risk of SARS-CoV-2 infection among Ontario physicians.
- To compare physician infection rates with non-physician controls by specialty.
Main Methods:
- Retrospective cohort study analyzing polymerase chain reaction (PCR) confirmed SARS-CoV-2 infections.
- Comparison of physicians (n=30,617) with community-matched controls (n=29,763) from March 2020 to December 2022.
- Assessment of secondary outcomes including hospitalization, critical care use, and mortality.
Main Results:
- Physicians had a 20% SARS-CoV-2 infection rate (6172 cases).
- Higher infection risk was observed in female physicians, those in long-term care, and pediatricians.
- Physicians showed increased infection risk during early pandemic waves (OR 1.38) but not from wave 3 onward (OR 0.93).
Conclusions:
- Physician SARS-CoV-2 infection rates exceeded community controls early in the pandemic but normalized later.
- Specialties like long-term care and pediatrics presented higher risks for physicians.
- Physicians experienced lower hospitalization rates post-infection compared to controls.
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