Investigation of Food Poisoning Outbreak in Polling Stations, Tambon Na Muenag, Mueang District, Prachin Buri Province, 22th April 2012

Abstract

Background : Food poisoning outbreak was detected by a nurse at Emergency Room of Chao Phya Abhaibhubejhr Hospital, Prachinburi Province on 22^th April 2012. The investigation was initiated by the Surveillance and Rapid Response Team with the aims to verify diagnosis and confirm outbreak, describe epidemiological characteristics, implement control measures and formulate recommendations for further prevention.
Methods : A descriptive study was conducted in the hospital through the reviews of the medical records, interviewed cases. Active case finding was performed with a case definition of acute food poisoning. Rectal swab and self-administered questionnaires about food eaten were completed by cases. Food handlers were interviewed about food preparation and rectal swab together with hand swab of them were examined to identify food borne diseases pathogens. Sample of food was sent to be cultured. Food preparation sites were evaluated. Food containers were swab for pathogens.
Results : 82 food poisoning patients (Attack rate 29.18 %) ,met the case definition, participated in Polling Stations, Tambon Na Muenag, Mueang District, Prachinburi Province, 22 April 2012. Most common symptoms were nausea vomiting (80.49 %) and abdominal pain (46.34%). Regarding common source epidemic curve picture, average incubation period was 3 hours 26 minutes. The case-control analysis demonstrated that shrimp paste fried rice was significantly associated with this outbreak (odds ratio = 37.22, 95%CI = 10.80 – 153.59). Staphylococcus aureus was found in shrimp paste fried rice. Rectal swab culture found no pathogen. Interviews with responsible food handlers regarding cooking processes showed poor hygienic procedures.
Conclusions : This was a confirmed outbreak of Staphylococcus aureus food poisoning in Polling Station from shrimp paste fried rice. Interviews with responsible food handlers regarding cooking processes suggested that poor hand hygiene might cause this event, especially when large amount of food were prepared. To prevent future outbreaks, education programs on proper sanitation and cooking processes should be provided for food handlers.