An outbreak of Coronavirus disease 2019 (COVID-19) in a police station in Province A, Thailand during 19-27 March 2020

Abstract

Background: During 19th-27th March 2020, Department of Disease Control investigated a confirmed case of coronavirus disease 2019. The case was a 45-year-old man, working as policeman in Province A. The objectives were to confirm the outbreak, identified closed contacts and implement immediate control measures.
Methods: The investigation team reviewed the index case’s medical records and interviewed for the travel and contact history during two weeks before and after onset. High risk contacts were defined as two conditions. Firstly, staying less than one meter and chat at least five minutes without mask or standing closed to the confirmed case when he sneezed or cough. Secondly, staying in a closed space within one meter with a confirmed case for 15 minutes without mask. We collected Nasopharyngeal swab from all high-risk contacts. The specimens were tested for RT-PCR at the National Institute of Health. Other contacts were requested to do home quarantine and measure body temperature for 14 days after the last contact. The environmental investigation was done at police station to identify the risk of transmission via sharing equipment or facilities. The national recommendations were implemented as immediate control measures.
Results: There were 12 confirmed cases including 9 officers, 2 patients’ family members, and 1 inmate. Female to male ratio was 1:5, the median age was 46 years. The epidemic curve suggests common factor started on 9th March 2020 and peak on 17th March 2020. The attack rate at the police station was 7.14%. The secondary attack rate of high-risk contact at the police station was 10.81% comparing to household contact was 9.52% (p-value = 0.61). Twenty-five percent of confirmed were asymptomatic. During the outbreak, soap or alcohol gel were limited. Wearing mask was not practiced by most personals. Working space was not adequate for physical distancing.
Conclusions: The high secondary attack rate of contact at workplace may be the result of long hours working and in adequate space. For the findings of this study suggests the important to emphasis the control measure at work including 100% wearing mask, physical distancing and working from home.