An investigation the outbreak of Food Poisoning Disease in School A, Hat Yai District, Songkhla Province, Thailand during 13-18 September 2024

Abstract

On September 12^th, 2024, the Office of Disease Prevention and Control Region 12 Songkhla Province received notification from the Songkhla Public Health Office. 54 suspected food poisoning cases were found in a cluster at School A in Hat Yai District, Songkhla Province.  Most patients have symptoms of vomiting, diarrhea, headache, and fever. The investigation team started an outbreak investigation during September 13^th-18^th, 2024. The objectives aimed to confirm diagnosis and outbreak, study epidemiological characteristics, identify the cause, identify the source and risk factor of the outbreak, and recommend control and prevention measures. The descriptive epidemiological studies, analytic studies, and environmental studies, we collected samples for testing. The results of the study total 78 cases met the case definition and the overall attack rate was 33.3% (78/234). The median age was 14.5 years with a minimum of 3 years and a maximum of 55 years. The highest attack rate in teachers (48.8%) followed by students (30.8%) and staff (22.7%) Majority of the cases developed vomit (75.6%), followed by abdominal pain (74.4%) and Nausea (67.9%). The outbreak pattern was a continuous common source. The molecular testing in the stool samples was positive Aeromonas caviae for 1 case and positive Norovirus GII for 1 case. Vomit samples were positive Norovirus GII for 1 case. Water was positive Aeromonas caviae for 1 sample. Risk factors found that the artesian well, which is a water source away from the septic tank, is less than the standard. The discussions and conclusions causative agents of this food poisoning outbreak are Aeromonas and Norovirus GII with contamination in the water system. The recommended that schools improve the quality of water used from groundwater sources by destroying germs in the system, adding an automatic chlorine refill system, or considering using provincial waterworks.