To determine the burden of Salmonella infections in the United States, Foodborne Diseases Active Surveillance Network (FoodNet) investigators conducted population-based active surveillance for culture-confirmed Salmonella infections during 1996-1999 at FoodNet laboratories. In addition, all clinical microbiology FoodNet laboratories were surveyed to determine their practices for isolating Salmonella. Telephone interviews were also conducted among residents of the FoodNet sites to determine the proportion of persons with diarrheal illness who sought medical care and the proportion who submitted stool specimens for bacterial culture. Using our model, we estimated that there were 1.4 million nontyphoidal Salmonella infections in the United States, resulting in 168,000 physician office visits per year during 1996-1999. Including both culture-confirmed infections and those not confirmed by culture, we estimated that Salmonella infections resulted in 15,000 hospitalizations and 400 deaths annually. These estimates indicate that salmonellosis presents a major ongoing burden to public health.

This multistate outbreak of E. coli O157:H7 infections was associated with consumption of mesclun lettuce from a single producer. Molecular subtyping facilitated the epidemiological investigation. This investigation increased the knowledge about current production practices that may contribute to the contamination of lettuce by microbial pathogens. Lettuce production practices should be monitored for microbiological safety.

Active surveillance for laboratory-confirmed Salmonella serotype Enteritidis (SE) infection revealed a decline in incidence in the 1990s, followed by an increase starting in 2000. We sought to determine if the fluctuation in SE incidence could be explained by changes in foodborne sources of infection. We conducted a population-based case-control study of sporadic SE infection in five of the Foodborne Diseases Active Surveillance Network (FoodNet) sites during a 12-month period in 2002-2003. A total of 218 cases and 742 controls were enrolled. Sixty-seven (31%) of the 218 case-patients and six (1%) of the 742 controls reported travel outside the United States during the 5 days before the case's illness onset (OR 53, 95% CI 23-125). Eighty-one percent of cases with SE phage type 4 travelled internationally. Among persons who did not travel internationally, eating chicken prepared outside the home and undercooked eggs inside the home were associated with SE infections. Contact with birds and reptiles was also associated with SE infections. This study supports the findings of previous case-control studies and identifies risk factors associated with specific phage types and molecular subtypes.

Newport-MDRAmpC infection is acquired through the US food supply, most likely from bovine and, perhaps, poultry sources, particularly among persons already taking antimicrobial agents.

Objectives. From 2001 through 2005, African Americans accounted for the largest percentage of new cases of human immunodeficiency virus (HIV)/ acquired immunodeficiency syndrome (AIDS) in all age categories, especially among people aged 13 to 24 years. Although students attending historically black colleges and universities (HBCUs) report many of the behaviors that promote HIV transmission, their risk behaviors and HIV testing practices have not been well-characterized. We compared the demographic and behavioral characteristics of people who have been previously tested for HIV with those of people tested for the first time in this demonstration project to increase HIV testing at HBCUs. Methods. The Centers for Disease Control and Prevention and collaborating partners conducted rapid HIV testing and behavioral surveys at HBCUs in Arkansas, Georgia, Mississippi, and Washington, D.C., from January 2005 to April 2007. We recruited a convenience sample of students and community members at different campus venues including student health centers, dormitories, and student activity centers. Results. Our analysis included 5,291 people, 42% of whom reported they had never been tested for HIV. People who had been tested in the past were more likely to be older, believe they were at high risk for infection, have visited a health-care facility, and report behaviors that increased their risk of HIV infection. Conclusion. Respondents who believed they were at increased risk for HIV infection or reported behaviors that increased their risk for infection were more likely to have been tested for HIV. Future research should compare actual vs. perceived risk for HIV infection and contrast how each impacts HIV testing.

The marked decrease in the incidence of listeriosis may be related to the decrease in the prevalence of L. monocytogenes contamination of ready-to-eat foods since 1996. The crude incidence in 2003 of 3.1 cases per 1 million population approaches the government's Healthy People objective of 2.5 cases per 1 million population by 2005. Further decreases in listeriosis incidence will require continued efforts of industry and government to reduce contamination of food and continued efforts to educate consumers and clinicians.

To monitor risk factors for illness, we conducted a case-control study of sporadic Shiga toxin-producing Escherichia coli O157 (STEC O157) infections in 1999-2000. Laboratory-confirmed cases of STEC O157 infection were identified through active laboratory surveillance in all or part of seven states. Patients and age-matched controls were interviewed by telephone using a standard questionnaire. Information was collected on demographics, clinical illness, and exposures to food, water, and animals in the 7 days before the patient's illness onset. During the 12-month study, 283 patients and 534 controls were enrolled. STEC O157 infection was associated with eating pink hamburgers, drinking untreated surface water, and contact with cattle. Eating produce was inversely associated with infection. Direct or indirect contact with cattle waste continues to be a leading identified source of sporadic STEC O157 infections.

From 1996 to 2004, the incidence of Salmonella Javiana infections increased in FoodNet, the U.S. national active foodborne disease surveillance programme. Contact with amphibians and consumption of tomatoes have been associated with outbreaks of S. Javiana infection. To generate and test hypotheses about risk factors associated with sporadic S. Javiana infections, we interviewed patients with laboratory-confirmed S. Javiana infection identified in Georgia and Tennessee during August-October 2004. We collected data on food and water consumption, animal contact, and environmental exposure from cases. Responses were compared with population-based survey exposure data. Seventy-two of 117 identified S. Javiana case-patients were interviewed. Consumption of well water [adjusted odds ratio (aOR) 4.3, 95% confidence interval (CI) 1.6-11.2] and reptile or amphibian contact (aOR 2.6, 95% CI 0.9-7.1) were associated with infection. Consumption of tomatoes (aOR 0.5, 95% CI 0.3-0.9) and poultry (aOR 0.5, 95% CI 0.2-1.0) were protective. Our study suggests that environmental factors are associated with S. Javiana infections in Georgia and Tennessee.