In a study of Campylobacter infection in northwestern England, 2003England, -2006, C. jejuni multilocus sequence type (ST)-45 was associated with early summer onset and was the most prevalent C. jejuni type in surface waters. ST-45 is likely more adapted to survival outside a host, making it a key driver of transmission between livestock, environmental, and human settings.H uman campylobacteriosis shows a marked seasonality with a peak during the early summer months in many countries (1). The driving factors for this seasonality are not understood. Studies have shown a coincident seasonality of infection in chicken, livestock, and humans, and the possibility of a common environmental trigger has been suggested (2). In a recent study of the infl uence of climate on seasonality in England and Wales, incidence of campylobacteriosis was correlated with air temperature (with higher temperature indicating more cases at key points of the year) (3). This fi nding may relate to animal husbandry practices, especially animal housing (4).Studies have attempted to identify environmental reservoirs of infection in water sources; Campylobacter organisms have been successfully cultured from surface water (5), and campylobacteriosis has been linked with exposure to untreated water (6). We were interested in identifying the factors driving the early summer increase of cases in the United Kingdom and in investigating the role of environmental reservoirs. Preliminary data identifi ed multilocus sequence type (ST)-45 complex as a strain with possible transmission from environmental sources (7), and we have analyzed this complex in more detail. The StudyThe study population was defi ned as all human cases of laboratory-confi rmed Campylobacter infection with onset from April 2003 through March 2006, reported by residents in 4 local authorities in northwestern England, as previously described (7). All case-patients were asked detailed questions about their illnesses and possible exposures.Water samples were collected at least each fortnight from October 2003 through December 2005 as 2-L grab samples from sampling points on 2 rivers associated with the study area (River Mersey and River Wyre). Water samples were transported to the Food and Environmental Microbiology Laboratory, Royal Preston Hospital. Campylobacter species were isolated by the addition of 10 mL of the water sample to 90 mL of warmed Campylobacter enrichment broth (product CM0983, Oxoid Ltd, Basingstoke, UK) and incubated at 37°C for 24 hours, followed by incubation at 42°C for 24 hours. The enrichment broths were subcultured onto Campylobacter blood-free selective agar (charcoal cefoperazone deoxycholate agar product CM0739, Oxoid Ltd) at 37°C for 48 hours microaerobically, by using a microaerobic gas generating kit (product CN0025, Oxoid, Ltd). Campylobacter colonies were identifi ed by morphologic features and confi rmed by microaerobic and aerobic growth on blood agar. The colonies were then placed in Amies transport and sent to the laboratory Health Protection Age...

MLST can be used to describe and analyze the epidemiology of campylobacteriosis in distinct human populations.

This study uses multilocus sequence typing (MLST) to investigate the epidemiology of Campylobacter coli in a continuous study of a population in Northwest England. All cases of Campylobacter identified in four Local Authorities (government administrative boundaries) between 2003 and 2006 were identified to species level and then typed, using MLST. Epidemiological information was collected for each of these cases, including food and recreational exposure variables, and the epidemiologies of C. jejuni and C. coli were compared using case-case methodology. Samples of surface water thought to represent possible points of exposure to the populations under study were also sampled, and campylobacters were typed with multilocus sequence typing. Patients with C. coli were more likely to be older and female than patients with C. jejuni. In logistic regression, C. coli infection was positively associated with patients eating undercooked eggs, eating out, and reporting problems with their water supply prior to illness. C. coli was less associated with consuming pork products. Most of the cases of C. coli yielded sequence types described elsewhere in both livestock and poultry, but several new sequence types were also identified in human cases and water samples. There was no overlap between types identified in humans and surface waters, and genetic analysis suggested three distinct clades but with several "intermediate" types from water that were convergent with the human clade. There is little evidence to suggest that epidemiological differences between human cases of C. coli and C. jejuni are a result of different food or behavioral exposures alone.

Twenty-three of 50 members of an extended Dutch-German family and their close friends who ate raw homemade summer sausage became ill with trichinosis; 12 patients were hospitalized for an average of 10 days each. The sausage had been made in three different batches according to an old family recipe. One of the batches made from USDA-inspected pork was found to contain Trichinella spiralis larvae by two Illinois State laboratories. The other two batches were negative. Seventeen of the 23 patients submitted information on medical expenses incurred and wages lost because of the outbreak. These costs totaled almost $20,000. There is need for a nationwide program for controlling trichinosis in swine.