Outbreak Investigation of Trichinosis in Pua District, Nan Province, April - May 2012

Abstract

Nan Provincial Health Office was informed by Pua Crown Prince hospital, Pua district, Nan province on May 11^st, 2012 about a group of patients with muscle pain and diarrhea-like symptoms, with one dead case. PHO officer and SRRT team conducted joint outbreak investigation to confirm diagnosis and presence of the outbreak, determine the cause, risk factors, source and/or route of transmission in order to implement the appropriate and effective disease control. Case definition in this outbreak are the persons who live in Pua district and suffered from muscle pain or swelling on body, arm, leg, face or eyelid associated with at least one of these following symptoms; fever, headache, nausea, vomiting, abdominal pain, diarrhea or fatigue during April 18th to May 30^th, 2012. Descriptive epidemiological study was conducted by collecting demographic and clinical data from patient records. Patient’s exposure histories were collected during the outbreak investigation by individual interviewing. Blood and tissue samples of patients were sent to the laboratory. Blood samples of pig from related farm was also collected. 20 patients were found from our investigation. The first patient haved the onset on April 21^st, 2012 and last patient on May 7^th, 2012. Average age is 50.2 years old (range 24-72). All patients resides in Ban-Nakhum Village, Sila-pech sub-district, Pua District, Nan Province, they were 16 male and 4 female. Two patients form 20 were dead. Most patients suffered from muscle pain (95%), diarrhea (75%) and swelling of body parts (70%). Laboratory result indicated that all patients 80 Trichinella infection. Analytic study suggested that consuming of the raw pork were the risk factor. Upon further investigation, the team found that the raw pork come from black-pig meat raised by hill-tribe, peoples without inspected by livestock officer. Health education on food safety and the hazard of inappropriate food preparation to all people is required, along with the collaboration officers of the livestock for meat investigation on animal disease surveillance in the community should be encouraged.