Demographic and professional risk factors of SARS-CoV-2 infections among physicians in low- and middle-income settings: Findings from a representative survey in two Brazilian states

Abstract

Health workers (HWs) are a key resource for health systems worldwide, and have been affected heavily by the COVID-19 pandemic. Evidence is consolidating on incidence and drivers of infections, predominantly in high-income settings. It is however unclear what the risk factors may be for specific health professions, particularly in low- and middle-income countries (LMICs). We conducted a cross-sectional survey in a representative sample of 1,183 medical doctors registered with Brazil's Federal Council of Medicine in one developed (São Paulo) and one disadvantaged state (Maranhão). Between February-June 2021, we administered a telephone questionnaire to collect data on physicians' demographics, deployment to services, vaccination status, and self-reported COVID-19 infections. We performed descriptive, univariate, and multilevel clustered analysis to explore the association between physicians' infection rates, and their sociodemographic and employment characteristics. A generalized linear mixed model with a binomial distribution was used to estimate the adjusted odds ratio. We found that 35.8% of physicians in our sample declared having been infected with SARS-CoV-2 virus during the first year of the pandemic. The infection rate in Maranhão (49.2%) [95% CI 45.0-53.4] was almost twice that in São Paulo (24.1%) [95% CI 20.8-27.5]. Being a physician in Maranhão [95% CI 2.08-3.57], younger than 50 years [95% CI 1.41-2.89] and having worked in a COVID-19 ward [95% CI 1.28-2.27], were positively associated with the probability of infection. Conversely, working with diagnostic services [95% CI 0.53-0.96], in administrative functions [95% CI 0.42-0.80], or in teaching and research [95% CI 0.48-0.91] were negatively associated. Based on our data from Brazil, COVID-19 infections in LMICs may be more likely in health systems with lower physician-to-patient ratios, and younger doctors working in COVID-19 wards may be infected more frequently. Such findings may be used to identify policies to mitigate COVID-19 effects on HWs in LMICs.

Fig 1. Geographical location of the surveyed physicians in São Paulo and Maranhão.

Note to Fig 1: Points outside the states of São Paulo and Maranhão refer to registered physicians who have recently retired or are active in more than one state. The base layer map of Brazil is from the Brazilian Institute of Geography and Statistics. Link: https://www.ibge.gov.br/geociencias/organizacao-do-territorio/malhas-territoriais/15774-malhas.html?=&t=downloads.

Fig 2. Physician infection rates in the sample locations.