September 23, 2005

Salmonella Typhimurium: Canada
A few outbreaks and clusters related to S. Typhimurium infections were identified during April 2-July 1, 2005. In May, there were more than 50 cases related to a brunch in Ontario. The isolates were determined to be PT 104. Five cases of S. Derby, 5 cases of S. Berta and 1 case of S. Agona were also related to this outbreak. The beef roasts were identified as the probable source. Phage typing of S. Typhimurium isolates also led to the identification of a cluster of PT U302 in Ontario. In the first six months of 2005, 66 S. Typhimurium PT U302 isolates were observed in Canada (13% of isolates tested), 53 of them from Ontario, 11 from Québec and 2 from Alberta. A case-control study conducted in Ontario did not conclusively identify a likely source. A small outbreak of S. Typhimurium PT U302 had also been reported in Sweden in April. Four of those cases had been linked to mini salami imported from Germany but, this product had not been imported into Canada. In 2004, PT U302 accounted for 3.8% of the S. Typhimurium isolates tested in Canada, including 24 isolates from Québec and 6 from Ontario. In June, 11 cases of S. Typhimurium infection were reported in Manitoba when only 4 would have been expected. Five isolates were identified as PT 10. No information related to these cases was reported. A family outbreak involving 2 cases of S. Typhimurium was also identified in New Brunswick in June.
Source: National Microbiology Laboratory and the Foodborne, Waterborne and Zoonotic Infections Division, Public Health Agency of Canada, 7 September 2005

Vibrio Illnesses After Hurricane Katrina: United States
Hurricane Katrina made landfall on 29 August 2005, with major impact on the U.S. Gulf Coast. During 29 August-11 September, surveillance identified 22 new cases of Vibrio illness with 5 deaths in persons who had resided in two states. These illnesses were caused by V. vulnificus, V. parahaemolyticus, and nontoxigenic V. cholerae. These organisms are acquired from the environment and are unlikely to cause outbreaks from person-to-person transmission. No cases of toxigenic V. cholerae serogroups O1 or O139 were identified. Results of the investigation underscore the need for heightened clinical awareness, appropriate culturing of specimens from patients, and empiric treatment of illnesses (particularly those associated with wound infections) caused by Vibrio species. No confirmed cases of illness have been identified with onset after 5 September.
Source: Morbidity and Mortality Weekly Report Dispatch, Volume 54, 14 September 2005

Hepatitis A: Alabama
The Alabama Department of Public Health is investigating an outbreak of hepatitis A. Since the beginning of September, 13 cases have been reported from scattered areas of the state. However, it appears that most of these patients may have contracted the disease after eating raw oysters. Of the 11 patients who have been interviewed, 10 have eaten raw oysters in the period 2-6 weeks before getting sick. At least 5 eating establishments may have been the source of contaminated oysters. Traceback activities will attempt to determine where the oysters were harvested. The investigation is still in progress.
Source: News Release, Alabama Department of Public Health, 13 September 2005

Verotoxin-producing Escherichia coli (VTEC) O145: Slovenia
The regional Institute of Public Health in Kranj, Slovenia, has reported a fatal case of bloody diarrhoea caused by VTEC O145. On 8 August 2005, a 22 month old, previously healthy girl died of myocarditis associated with haemolytic uraemic syndrome (HUS). She had become ill on 3 August with bloody diarrhoea, but no fever or pain. She was admitted to hospital for two days and received symptomatic therapy. The day after she was discharged, her condition worsened, with neurological symptoms, and she was readmitted to hospital where the diagnosis of HUS was made. The girl lived in a rural area and had never travelled abroad. She had very limited contacts with other children and adults. The family used drinking water from a controlled local water supply. E. coli was never detected in this water during regular testing. The family did not keep farm animals, although the child had frequent contact with a domestic cat. The family made their own meals with meat bought from the local butchers in the village, and had bought minced meat to eat a few days before the child became ill. This is thought to be the most likely source of infection, but no meat was left over to test for E. coli.
Source: Eurosurveillance Weekly, Volume 10, Issue, 9, 15 September 2005

The details given are for information only and may be very provisional. Where incidents are considered of national importance and are ongoing, the initial report will be updated as new information becomes available.