Non-O157 Shiga Toxin–producing Escherichia coli Associated with Venison

News reports of “E. coli outbreaks” usually refer to Shiga toxin–producing E. coli O157. But there are other types of Shiga toxin–producing E. coli, often called STEC,about which less is known. For these other types of STEC, what is the source? What are the risk factors? An outbreak among 29 high school students in Minnesota provided some answers. The source of this outbreak was a white-tailed deer that had been butchered and eaten at the school. The risk factors for infection were handling raw or eating undercooked venison. To prevent this type of STECinfection, people should handle and cook venison with the same caution recommended for other meats

Prevalence of nasal colonization of methicillin-resistant Staphylococcus aureus in homeless and economically disadvantaged populations in Kansas City

Nasal colonization of methicillin-resistant Staphylococcus aureus (MRSA) plays an important role in the epidemiology and pathogenesis of disease. Situations of close-quarter contact in groups are generally regarded as a risk factor for community acquired MRSA strains due to transmission via fomites and person to person contact. With these criteria for risk, homeless individuals using shelter facilities, including showers and toilets, should be considered high risk for colonization and infection. The aim of this study was to determine the prevalence of nasal colonization of MRSA in a homeless population compared to established rates of colonization within the public and a control group of subjects from a neighboring medical school campus, and to analyze phylogenetic diversity among the MRSA strains. Nasal samples were taken from the study population of 332 adult participants, and analyzed. In addition, participants were surveyed about various lifestyle factors in order to elucidate potential patterns of behavior associated with MRSA colonization. Homeless and control groups both had higher prevalence of MRSA (9.8% and 10.6% respectively) when compared to the general population reported by previous studies (1.8%). However, the control group had a similar MRSA rate compared to healthcare workers (4.6%) while the homeless population had an increased prevalence. Risk factors identified in this study included male gender, age over 50 years and use of antibiotics within the past 3 months. Phylogenetic relationships between 9 of the positive samples from the homeless population were analyzed, showing 8 of the 9 samples had a high degree of relatedness between the spaA genes of the MRSA strains. This indicates that the same MRSA strain might be transmitted from person to person among homeless population. These findings increase our understanding of key differences in MRSA characteristics within homeless populations as well as risks for MRSA associated with being homeless, such as age and gender, which may then be a useful tool in guiding more effective prevention, treatment, and healthcare for homeless individuals