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Reinfection Incidences in Health Care Workers and Non-Health Care Workers: A Single-Center Study in a Turkish SARS-CoV-2 Patient Cohort

Published online by Cambridge University Press:  07 July 2025

Merve Atilgan Ala*
Affiliation:
Ege University Faculty of Medicine , Department of Pulmonary Medicine, Izmir, Türkiye
Raika Durusoy
Affiliation:
Ege University Faculty of Medicine , Department of Public Health, Izmir, Türkiye
Murat Ersel
Affiliation:
Ege University Faculty of Medicine , Department of Emergency Medicine, Izmir, Türkiye
Ruchan Sertoz
Affiliation:
Ege University Faculty of Medicine , Department of Medical Microbiology, Izmir, Türkiye
Bilgin Arda
Affiliation:
Ege University Faculty of Medicine , Department of Infectious Disease and Clinical Microbiology, Izmir, Türkiye
Su Ozgur
Affiliation:
Ege University Institute of Health Sciences , Translational Pulmonary Research Center (EgeSAM), Izmir, Türkiye
Ozlem Goksel
Affiliation:
Ege University Faculty of Medicine , Department of Pulmonary Medicine, Division of Immunology and Allergy, Laboratory of Occupational/Environmental Respiratory Diseases and Asthma, Ege University Institute of Health Sciences, Translational Pulmonary Research Center (EgeSAM), Izmir, Türkiye
*
Corresponding author: Merve Atilgan Ala; Email: merveatilgan11@gmail.com

Abstract

Background

The COVID-19 pandemic, which has killed millions of people worldwide, continues to be marked by waves of reinfections. We aimed to assess the incidence and clinical characteristics of reinfection in COVID- 19 cohort.

Material and Methods

A single-center descriptive study was conducted. Data were collected from all patients who tested positive for SARS-CoV-2 via PCR from March 18, 2020, the onset of the first major COVID-19 wave, until the end of 2020. All PCR-positive patients were followed-up, and those who had SARS-CoV-2 PCR positivity again at least 90 days after the initial onset were contacted via telemedicine.

Results

5814 patients diagnosed with COVID-19 with PCR positive in the first wave were included. The incidence of reinfection among the cohort of patients infected with SARS-CoV-2 during the initial wave of COVID-19 was 0.73%. Among healthcare workers, the 1-year reinfection rate was 2.14%, 3.9 times higher than non-healthcare workers. We observed that the clinical course was milder and less complicated in patients who had reinfection. In cases of reinfection among fully vaccinated individuals, statistically significantly fewer symptoms were observed.

Conclusions

We observed that healthcare workers are at approximately four times greater risk of reinfection. Reinfections generally presented with a milder clinical course.

Information

Type
Research Letters
Copyright
© The Author(s), 2025. Published by Cambridge University Press on behalf of Society for Disaster Medicine and Public Health, Inc

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