SUMMARY: We examined reported outbreaks of foodborne shigellosis in the USA from 1998 to 2008 and summarized demographic and epidemiological characteristics of 120 confirmed outbreaks resulting in 6208 illnesses. Most reported foodborne shigellosis outbreaks (n=70, 58%) and outbreak-associated illnesses (n=3383, 54%) were restaurant-associated. The largest outbreaks were associated with commercially prepared foods distributed in multiple states and foods prepared in institutional settings. Foods commonly consumed raw were implicated in 29 (24%) outbreaks and infected food handlers in 28 (23%) outbreaks. Most outbreaks (n=86, 72%) were caused by Shigella sonnei. Targeted efforts to reduce contamination during food handling at multiple points in the food processing and distribution system, including food preparation in restaurants and institutional settings, could prevent many foodborne disease outbreaks and outbreak-related illnesses including those due to Shigella.

Diarrhea is a leading cause of morbidity and mortality in people living with HIV (PLHIV) in Africa. The impact of a point-of-use water chlorination and storage intervention on diarrheal-disease risk in a population of HIV-infected women in Lagos, Nigeria was evaluated. A baseline survey was performed, followed by six weeks of baseline diarrhea surveillance consisting of weekly home visits, distribution of free water chlorination products and safe storage containers to project participants, and continued weekly home-based diarrhea surveillance for 15 additional weeks. To confirm use of the water chlorination product, during each home visit, stored water was tested for residual chlorine. About 187 women were enrolled. At baseline, 80% of women had access to improved water supplies and 95% had access to sanitation facilities. Following distribution of the intervention, water stored in participants' households was observed to have residual chlorine during 50-80% of home visits, a sign of adherence to recommended water-treatment practices. Diarrhea rates in project participants were 36% lower in the post-intervention period than during the baseline period (p=0.04). Diarrhea rates were 46% lower in the post-intervention period than the baseline period among project participants who were confirmed to have residual chlorine in stored water during 85% or more of home visits (p=0.04); there was no significant difference in diarrhea rates between baseline and post-intervention periods in participants confirmed to have residual chlorine in stored water during less than 85% of home visits. The percent change in diarrhea rates between baseline and post-intervention surveillance periods was statistically significant among non-users of prophylactic antibiotics (-62%, p=0.02) and among persons who used neither prophylactic antibiotics nor antiretroviral treatment (-46%, p=0.04). Point-of-use water treatment was associated with a reduced risk of diarrhea in PLHIV. Regular water treatment was required to achieve health benefits.

CONTEXT: Typhoid fever in the United States has increasingly been due to infection with antimicrobial-resistant Salmonella ser Typhi. National surveillance for typhoid fever can inform prevention and treatment recommendations. OBJECTIVE: To assess trends in infections with antimicrobial-resistant S. Typhi. DESIGN: Cross-sectional, laboratory-based surveillance study. SETTING AND PARTICIPANTS: We reviewed data from 1999-2006 for 1902 persons with typhoid fever who had epidemiologic information submitted to the Centers for Disease Control and Prevention (CDC) and 2016 S. Typhi isolates sent by participating public health laboratories to the National Antimicrobial Resistance Monitoring System Laboratory at the CDC for antimicrobial susceptibility testing. MAIN OUTCOME MEASURES: Proportion of S. Typhi isolates demonstrating resistance to 14 antimicrobial agents and patient risk factors for antimicrobial-resistant infections. RESULTS: Patient median age was 22 years (range, <1-90 years); 1295 (73%) were hospitalized and 3 (0.2%) died. Foreign travel within 30 days of illness was reported by 1439 (79%). Only 58 travelers (5%) had received typhoid vaccine. Two hundred seventy-two (13%) of 2016 isolates tested were resistant to ampicillin, chloramphenicol, and trimethoprim-sulfamethoxazole (multidrug-resistant S. Typhi [MDRST]); 758 (38%) were resistant to nalidixic acid (nalidixic acid-resistant S. Typhi [NARST]) and 734 NARST isolates (97%) had decreased susceptibility to ciprofloxacin. The proportion of NARST increased from 19% in 1999 to 54% in 2006. Five ciprofloxacin-resistant isolates were identified. Patients with resistant infections were more likely to report travel to the Indian subcontinent: 85% of patients infected with MDRST and 94% with NARST traveled to the Indian subcontinent, while 44% of those with susceptible infections did (MDRST odds ratio, 7.5; 95% confidence interval, 4.1-13.8; NARST odds ratio, 20.4; 95% confidence interval, 12.4-33.9). CONCLUSION: Infection with antimicrobial-resistant S. Typhi strains among US patients with typhoid fever is associated with travel to the Indian subcontinent, and an increasing proportion of these infections are due to S. Typhi strains with decreased susceptibility to fluoroquinolones.