COVID-19 School Cluster Investigation in Bantul District Yogyakarta, Indonesia, February 2022
Bantul is a district with the second-highest number of COVID-19 cases in Yogyakarta Province. On January 30, 2022, Bantul 1 Public Health Center (PHC) reported a case of a student at Senior High School 2 Bantul (SMAN 2 Bantul). The investigation was initiated to confirm the COVID-19 cluster in the school and identify the risk
A 1:1 case-control study was conducted. Cases were school residents of SMAN 2 Bantul with positive PCR results in January-February 2022. Controls were school residents of SMAN 2 Bantul with negative COVID-19 from the PCR laboratory results in January-February 2022. Interviews were conducted using a structured questionnaire. Bantul 1 PHC collected oropharyngeal and nasopharyngeal swabs. Specimens were sent to the regional laboratory and tested with RT-PCR. The variables measured were demographic characteristics, comorbidities, COVID-19 risk factors, and healthy behaviors.
There were 96 confirmed cases of COVID-19 from 891 school residents (attack rate 10.9%). Cases consist of 92 students, two teachers, and two employees. Seventy-nine new cases occurred after the school’s anniversary celebration including healthy walks and art performances with minimal health protocols. Multivariate analysis with logistic regression obtained significant variables are the habit of not washing hands with soap OR 12.79 (95% CI 4.09-39.95), the habit of not physically distancing OR 16.80 (95% CI 5.05-55.87), and ventilation conditions during learning OR 5.56 (95% CI 1.63-18.98).
There was a COVID-19 cluster outbreak at SMAN 2 Bantul. The risk factors associated with the outbreak are the habit of not washing hands with soap, the habit of not physically distancing, and ventilation conditions during learning. Improvements to the implementation of health protocols, including mass gathering activities and supporting facilities for health protocols, must be a concern for schools to reduce the spread of COVID-19.