J Prev Med Public Health.
2005 May;38(2):182-188.
Epidemiologic Investigation on Sporadic Occurrence of Shigellosis in a Subcounty of Cheongwon County in Chungbuk Province in 2003
- Affiliations
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- 1Division of Epidemic Intelligence Service, Korea Center for Disease Control and Prevention, Korea.
- 2Department of Family Medicine, Seoul Paik Hospital, Inje University College of Medicine, Korea.
- 3Department of Microbiology, Chungbuk Institute of Health and Environment Research, Korea.
- 4Division of Enteric Infections, Department of Bacteriology, National Institute of Health, Korea.
- 5Division of Bioterrorism Preparedness and Response, Korea Center for Disease Control and Prevention, Korea.
- 6Department of Preventive Medicine, College of Medicine, Chungbuk National University, Korea. jwkang@pm.cbu.ac.kr
Abstract
OBJECTIVES
This study was undertaken to investigate the source of infection and mode of transmission of shigellosis, which occurred sporadically among residents and students in a subcounty of Cheongwon county, Chungbuk province, Korea, from June 4 to July 3 2003. METHODS: 692 subjects completed a questionnaire and provided a swab for microbiological examinations, and 7 environmental specimens were examined for bacterial organisms. PFGE (pulsed-field gel electrophoresis) and fingerprinting were performed to find the genetic relationship among the temporally associated sporadic isolates. RESULTS: A total of 29 patients had symptoms consistent with the case definition, with 13 confirmed and 16 suspected cases. The frequency of diarrhea was 6 times or more a day (80.8%), with a duration of 1 to 4 days (88.5%) in most cases. The most common symptoms accompanying the diarrhea were fever (80.9%) followed by abdominal pain (76.9%), headache (65.4%), chill (61.5%), vomiting (46.2%) and tenesmus (15.4%). The epidemic curve was characteristic of a person-to-person transmission. The PFGE and fingerprinting demonstrated identical or similar DNA patterns among the 3 Shigella sonnei isolates (A51, A53 and A61 types) found in this outbreak. CONCLUSION: A genetically identical strain of S. sonnei was estimated to be the cause of this outbreak, and the mode of transmission was most likely person-to-person.