Evaluation of pot-chlorination of wells during a cholera outbreak, Bissau, Guinea-Bissau, 2008.

We evaluated the ability of UNICEF-designed pot-chlorinators to achieve recommended free residual chlorine (FRC) levels in well water in Bissau, Guinea-Bissau, during a cholera outbreak. Thirty wells were randomly selected from six neighbourhoods. Pot-chlorinators--perforated plastic bottles filled with gravel, sand and calcium hypochlorite granules--were placed in each well. FRC was measured before and 24, 48 and 72 h after placement and compared with World Health Organization (WHO)-recommended levels of 21 mg L(-1) for well water during cholera outbreaks and 0.2-5 mg L 1 in non-outbreak settings. Presence of well covers, distance from wells to latrines, and rainfall were noted. Complete post-chlorination data were collected from 26 wells. At baseline, no wells had FRC>0.09 mg L(-1). At 24, 48 and 72 h post-chlorination, 4 (15%), 1 (4%) and 0 wells had FRC>or=1 mg L(-1) and 16 (62%), 4 (15%) and 1 (4%) wells had FRC between 0.2 and 5 mg L(-1), respectively. Several families reported discontinuing household water chlorination after wells were treated with pot-chlorinators. Pot-chlorinators failed to achieve WHO-recommended FRC levels in well water during a cholera outbreak, and conveyed a false sense of security to local residents. Pot-chlorination should be discouraged and alternative approaches to well-water disinfection promoted.

Salmonella typhimurium infections associated with peanut products.

BACKGROUND: Contaminated food ingredients can affect multiple products, each distributed through various channels and consumed in multiple settings. Beginning in November 2008, we investigated a nationwide outbreak of salmonella infections. METHODS: A case was defined as laboratory-confirmed infection with the outbreak strain of Salmonella Typhimurium occurring between September 1, 2008, and April 20, 2009. We conducted two case-control studies, product "trace-back," and environmental investigations. RESULTS: Among 714 case patients identified in 46 states, 166 (23%) were hospitalized and 9 (1%) died. In study 1, illness was associated with eating any peanut butter (matched odds ratio, 2.5; 95% confidence interval [CI], 1.3 to 5.3), peanut butter-containing products (matched odds ratio, 2.2; 95% CI, 1.1 to 4.7), and frozen chicken products (matched odds ratio, 4.6; 95% CI, 1.7 to 14.7). Investigations of focal clusters and single cases associated with nine institutions identified a single institutional brand of peanut butter (here called brand X) distributed to all facilities. In study 2, illness was associated with eating peanut butter outside the home (matched odds ratio, 3.9; 95% CI, 1.6 to 10.0) and two brands of peanut butter crackers (brand A: matched odds ratio, 17.2; 95% CI, 6.9 to 51.5; brand B: matched odds ratio, 3.6; 95% CI, 1.3 to 9.8). Both cracker brands were made from brand X peanut paste. The outbreak strain was isolated from brand X peanut butter, brand A crackers, and 15 other products. A total of 3918 peanut butter-containing products were recalled between January 10 and April 29, 2009. CONCLUSIONS: Contaminated peanut butter and peanut products caused a nationwide salmonellosis outbreak. Ingredient-driven outbreaks are challenging to detect and may lead to widespread contamination of numerous food products.

Developing explicit positive beers criteria for preferred central nervous system medications in older adults.

BACKGROUND: The Beers criteria have been extensively used over the past decade to identify and evaluate potentially inappropriate medication use in adults 65 years of age and older in the United States. In contrast to the Beers criteria, the purpose of this pilot initiative was to develop a new set of explicit criteria for determining preferred (rather then potentially inappropriate) medications to use in older adults, using similar methodology as used in the three iterations of the Beers criteria. This initiative organized its evaluations around classes of medications that are both frequently used and associated with drug-related problems in older adults-central nervous system (CNS) medications. METHODS: This pilot study used a modified Delphi method-a set of procedures and methods for reaching group consensus for a subject matter in which precise information is lacking-to determine medications that are preferred for use in persons 65 years of age or older known to have specific medical conditions. Medications were selected as preferred because they are both effective, based upon a thorough evaluation of the clinical evidence, and pose less risk for older persons compared with alternative medications for the condition. Expert panelists evaluated 78 individual medications within four medical conditions (dementia, depression, Parkinson's disease, and psychosis). RESULTS: This study identified 13 preferred medications to be used in older adults with these conditions. CONCLUSIONS: This study expands explicit criteria to more precisely define preferred medication use in older adults. This refinement of the Beers criteria will enable providers to select medications with the greatest benefit-to-risk ratio for older adults, thereby minimizing drug-related problems. These criteria will need to be expanded to include other medication classes and medical conditions frequently encountered in older adults.

Field evaluation of crystal VC Rapid Dipstick test for cholera during a cholera outbreak in Guinea-Bissau.

OBJECTIVES: To evaluate performance characteristics and ease of use of the new commercially available Crystal VC Rapid Dipstick (VC) test (Span Diagnostics, India) for Vibrio cholerae O1 and O139. METHODS: Whole stool was collected from patients presenting to a hospital cholera ward during a 2008 epidemic in Guinea-Bissau. The VC test on stool samples was conducted on-site; samples were subsequently stored in Cary-Blair transport media and sent to the Centers for Disease Control and Prevention for diagnostic testing by culture and polymerase chain reaction (PCR). In addition, four local laboratory technicians who were unfamiliar with the test were provided with stool samples, the VC test kit, and simple written instructions and asked to perform the test and interpret results. RESULTS: A total of 101 stool specimens were collected and tested. Compared with PCR, the test was 97% sensitive and 71-76% specific. Laboratory technicians in Bissau performed the test and interpreted results correctly using only simple written instructions. CONCLUSIONS: The VC test may be useful for cholera diagnosis in outbreak situations where laboratory capacity is limited.