Incidence and Source of COVID‑19 Infection Among Health Care Workers in a Tertiary Hospital in South India—A Prospective Cohort Study

Yogesh Mohan, B. Charumathi, V. M. Anantha Eashwar, Timsi Jain, V. K. Abiramasundari


Background: Data for COVID‑19 incidence and the source of infection among health care workers (HCWs) in Indian population are limited. The main objective of the study was to assess the incidence of COVID‑19 infection and identify the source of infection among the HCWs in a tertiary teaching hospital.

Methods: A prospective cohort study was conducted among the 2134 HCWs recruited by purposive sampling from a tertiary teaching hospital from May to August 2020 (4‑month period—123 days). Over the 4‑month period, all the HCWs who had symptoms or those were close contacts of COVID positive patients were traced and tested using validated COVID diagnostic test (reverse transcription–polymerase chain reaction [RT–PCR] test). A semi‑structured questionnaire was used to interview each positive HCW to identify the source of exposure of the infection.

Results: Incidence proportion was 9.3% among HCWs and was two times higher among males compared to females. Hazard ratio was found to be higher among males and HCWs working in the non‑COVID areas. Test positivity rate was found to highest (around 57.8%) among those aged less than 30 years. The most common source of infection was infected HCW colleagues (40.9%) followed by exposure to patients in non‑COVID areas (27.3%). Only 5.1% of total infection was found in HCWs who had worked in COVID zones.

Conclusions: People working in non‑COVID areas, those using shared workplace, dining halls, and staff hostels, must follow strict COVID protocols by using appropriate Personal Protective Equipment (PPE) and following social distancing measures.


Contact tracing; COVID‑19; epidemiology; medical staff

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