title: Detection and typing of Campylobacter jejuni and Campylobacter coli and analysis of indicator organisms in three waterborne outbreaks in Finland.
abstract: Waterborne outbreaks associated with contamination of drinking water by Campylobacter jejuni are rather common in the Nordic countries Sweden, Norway, and Finland, where in sparsely populated districts groundwater is commonly used without disinfection. Campylobacters, Escherichia coli, or other coliforms have rarely been detected in potential sources. We studied three waterborne outbreaks in Finland caused by C. jejuni and used sample volumes of 4,000 to 20,000 ml for analysis of campylobacters and sample volumes of 1 to 5,000 ml for analysis of coliforms and E. coli, depending on the sampling site. Multiple samples obtained from possible sources (water distribution systems and environmental water sources) and the use of large sample volumes (several liters) increased the chance of detecting the pathogen C. jejuni in water. Filtration of a large volume (1,000 to 2,000 ml) also increased the rate of detection of coliforms and E. coli. To confirm the association between drinking water contamination and illness, a combination of Penner serotyping and pulsed-field gel electrophoresis (digestion with SmaI and KpnI) was found to be useful. This combination reliably verified similarity or dissimilarity of C. jejuni isolates from patient samples, from drinking water, and from other environmental sources, thus confirming the likely reservoir of an outbreak.
authors.affiliation: Department of Food and Environmental Hygiene, University of Helsinki, PO Box 57, 00014 Helsinki University, Finland. marja-liisa.hanninen@helsinki.fi
authors.forename: Marja-Liisa
authors.initials: ML
authors.lastname: Hänninen
authors.forename: H
authors.initials: H
authors.lastname: Haajanen
authors.forename: T
authors.initials: T
authors.lastname: Pummi
authors.forename: K
authors.initials: K
authors.lastname: Wermundsen
authors.forename: M-L
authors.initials: ML
authors.lastname: Katila
authors.forename: H
authors.initials: H
authors.lastname: Sarkkinen
authors.forename: I
authors.initials: I
authors.lastname: Miettinen
authors.forename: H
authors.initials: H
authors.lastname: Rautelin
mesh_terms: D000818:Animals; D015373:Bacterial Typing Techniques; D002169:Campylobacter Infections / Q000453:epidemiology* / Q000382:microbiology; D017000:Campylobacter coli / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D016123:Campylobacter jejuni / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D015252:Deoxyribonucleases, Type II Site-Specific / Q000378:metabolism; D004196:Disease Outbreaks; D016521:Electrophoresis, Gel, Pulsed-Field; D004755:Enterobacteriaceae / Q000145:classification / Q000235:genetics / Q000302:isolation & purification; D004926:Escherichia coli / Q000145:classification / Q000235:genetics / Q000302:isolation & purification; D005387:Finland / Q000453:epidemiology; D006801:Humans; D012703:Serotyping; D014871:Water Microbiology; D014876:Water Pollution; D014881:Water Supply
chemical_list: C025651:CCCGGG-specific type II deoxyribonucleases; D015252:Deoxyribonucleases, Type II Site-Specific; C029312:GGTACC-specific type II deoxyribonucleases