![[ Visit Client Website ]](images/banner.png)
BACKGROUND: In Alaska, campylobacteriosis has been reportable to public health since 1984. Campylobacter is the most frequently reported bacterial enteric pathogen, averaging 90 cases annually. Routine pulsed-field gel electrophoresis (PFGE) of Campylobacter isolates began in 2002 at the Alaska State Public Health Laboratory (ASPHL); however, Campylobacter isolates are neither nationally reportable nor routinely subject to PFGE, with limited resources being the most often-cited reason. We summarized Alaska’s experience in universally investigating Campylobacter isolates to demonstrate the value in more fully characterizing the public health burden.
METHODS: ASPHL classified all Campylobacter PFGE data by frequency of pattern matches during 2004-2013. Alaska data submitted to the National Outbreak Reporting System (NORS) and individual case/cluster reports collected through mandatory reporting were also summarized.
RESULTS: From 2004-2013, 669 Campylobacter isolates were processed at ASPHL; 45 were from environmental sources. Excluding environmental isolates, 268 (43%) isolates comprised 23 outbreaks logged in NORS; five (22%) were attributed to contaminated food, two (9%) to handling live poultry, and one (4%) each to unfiltered water and person-to-person transmission. Thirteen (57%) outbreaks had an undetermined source. Additionally, 82 isolates (13%) comprising 30 clusters (2 or more isolates with a matching pattern and a plausible epidemiologic link) prompted extra attention including follow-up interviews, field investigations, or public facility/water source inspections. Some illnesses acquired in Alaska but identified outside were not fully appreciated because PFGE was not routinely performed in those locations. The remaining 274 isolates (44%) were classified as sporadic without a match or other epidemiologically-linked illnesses. PFGE coupled with epidemiologic data was critical in early identification of two larger smoldering Campylobacter outbreaks because the food sources (raw peas and raw milk) were consumed for many weeks and a typical point source distribution was not readily appreciated before PFGE data were available.
CONCLUSIONS: Over half of Alaska Campylobacter cases were linked to an outbreak/cluster, leaving 44% classified as truly sporadic. Although that estimate is vastly different than the >90% national estimate, it is not surprising because uninvestigated cases are unlikely to be linked to other illness. Routine reporting and PFGE of Campylobacter isolates in Alaska has contributed to more fully documenting the infectious gastrointestinal disease burden and prompting more public health investigations and subsequent interventions. Cost-effectiveness of these practices has not been formally assessed; paradoxically, were Alaska to limit epidemiologic and laboratory follow-up, we would expect documented outbreaks to decrease regardless of changes in absolute case reports.