An outbreak investigation of acute diarrhea in a school, Sanpatong District, Chiangmai Province, Thailand, September 2020

Abstract

On 14 September 2020, thirteen acute diarrhea patients, all of them lived at one school in Sanpatong district, were notified to SRRT Sanpatong, Chiangmai province. We investigated this event to confirm diagnosis, confirm outbreak, describe the epidemiology of outbreak and implement control measures. We conducted the descriptive study by reviewing medical records, interviewing patients who had acute diarrhea at Sanpatong hospital and conducted the active case finding. Case-control study was conducted by questionnaire for searching foods which had risk to cause of acute diarrhea. Environmental study was conducted by surveying canteen of school and interviewing cooks. Laboratory study was conducted by collecting rectal swab for searching pathological organism by stool culture and collecting sample for searching coliform bacteria by SI-2 testing. Results showed twenty-eight cases had acute diarrhea. Male were 39.29 percent and female 40.71 percent. Age average was 14.17-year-olds. Attack rate in female more than male. The most of attack rate was 12-year-old and secondary school grade 7. The total attack rate was 13.15%.  Clinical presentations of patients were loose stool, abdominal pain, liquid instead of formed stool, fatigue and nausea/vomiting. Food which had risk to cause of acute diarrhea was pork snack & fresh vegetable.  Environmental study showed canteen had good food sanitation standard. Laboratory study showed no pathological organism, Vibrio spp., Salmonella spp. และ Shigella spp., from stool culture but we found coliform bacteria in kitchenware, food container and cook’s hand. So that we confirmed outbreak of acute diarrhea in a school, Sanpatong District, Chiangmai between 4-24 September 2020.