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Marc-Alain Widdowson

Publications and source records attributed to Marc-Alain Widdowson.

22 records · Page 2Linked to original sources

Foodborne viral gastroenteritis: challenges and opportunities.

Norwalk-like viruses (NLVs) are estimated to be the most common causes of foodborne disease in the United States, accounting for two-thirds of all food-related illnesses. The epidemiologic features and disease burden associated with NLVs have, until recently, been poorly understood because of the lack of sensitive detection assays and the underuse of available diagnostic tools. However, the application of molecular techniques to diagnose and investigate outbreaks of infection during recent years has led to a growing appreciation of the importance of these agents. NLVs are a principal cause of outbreaks of acute-onset vomiting and diarrhea in all age groups-most commonly, via contamination of uncooked foods by infected foodhandlers, but also via foods contaminated at their sources, such as oysters and raspberries. NLVs may also account for >10% of sporadic cases of gastroenteritis in children and adults. Future research will focus on the development of easy-to-use diagnostic assays based on antigen and antibody detection as well as vaccine development. Implementation of simple prevention measures, including correct food-handling practices, will continue to be a priority.

Caliciviridae Infections↗

An outbreak of diarrhea in a neonatal medium care unit caused by a novel strain of rotavirus: investigation using both epidemiologic and microbiological methods.

OBJECTIVE: In December 1999, an outbreak of diarrhea was reported in a general hospital neonatal medium care unit (NMCU) caused by a novel strain of rotavirus with genotype P[6], G9. An investigation was conducted to determine risk factors for illness among neonates. DESIGN: Rotavirus diagnosis was by latex agglutination and typing by reverse transcriptase polymerase chain reaction. A case-control study was performed using data collected from medical records on exposures in a 3-day period before illness (cases) or a random 3-day period (controls). Environmental swabs were tested for rotavirus. Antenatal blood samples from mothers and blood samples provided by hospital staff were analyzed for rotavirus antibodies. RESULTS: Fifty-six cases of rotaviral illness were confirmed by latex agglutination. Forty-seven of these were among 118 neonates exposed to the NMCU (attack rate, 40%). There was a 4-week period with no clinical cases in the course of the outbreak. Increased frequency (> or = 15 times in 3 days) of ungloved nasogastric feeding was a significant risk factor (adjusted odds ratio, 8.79), controlling for birth weight and gestational age. Environmental sampling showed persistence of the virus on ward surfaces despite cleaning. None of 24 NMCU staff members had high levels of antibodies against P[6], G9. Three (8%) of 38 mothers had high antibody levels; 2 had infants who became ill. The outbreak ended with a 7-day ward closure, disinfection, and introduction of gloved nasogastric feeding. CONCLUSIONS: Case-control studies can be successful in identiffying risk factors for nosocomial outbreaks of diarrhea. High levels of rotavirus antibodies in mothers may not protect infants. The environment may be the most important reservoir of rotavirus during outbreaks.

Case-Control Studies↗

Salmonella enterica serotype Enteritidis phage type 4b outbreak associated with bean sprouts.

In November 2000 in the Netherlands, an outbreak of Salmonella enterica serotype Enteritidis phage type 4b was investigated. Eating bean sprouts was the only exposure associated with S. Enteritidis pt 4b infection (matched odds ratio 13.0, 95% confidence interval 2.0-552.5). Contaminated seeds were the most likely cause of contamination of the sprouts. The sprout grower applied a concentration of hypochlorite solution that was too low for seed disinfection.

Adolescent↗

Epidemiology of urban canine rabies, Santa Cruz, Bolivia, 1972-1997.

We analyzed laboratory data from 1972 to 1997 from Santa Cruz, Bolivia, to determine risk factors for laboratory canine samples' testing positive for Rabies virus (RABV). Of 9,803 samples, 50.7% tested positive for RABV; the number of cases and the percentage positive has dropped significantly since 1978. A 5- to 6-year cycle in rabies incidence was clearly apparent, though no seasonality was noted. Male dogs had significantly increased odds of testing positive for RABV (odds ratio [OR]=1.14), as did 1- to 2-year-old dogs (OR=1.73); younger and older dogs were at lower risk. Samples submitted from the poorer suburbs of the city were more likely to test positive for RABV (OR=1.71). Knowledge of the distribution of endemic canine rabies in an urban area will help focus control measures in a resource-poor environment.

Aging↗