Biomedical subjects

Malinda Kennedy

Publications and source records attributed to Malinda Kennedy.

7 recordsLinked to original sources

PubMed2004

Dramatic decrease in the incidence of Salmonella serotype Enteritidis infections in 5 FoodNet sites: 1996-1999.

Salmonella serotype Enteritidis (SE) emerged as the most common Salmonella serotype among infected persons in the United States during the 1980s and 1990s, with infections reaching a peak in 1995. During the past decade, farm-to-table control measures have been instituted in the United States, particularly in regions with the highest incidence of SE infection. We report trends in the incidence of SE in the 5 original surveillance areas of the Foodborne Diseases Active Surveillance Network during 1996-1999: Minnesota, Oregon, and selected counties in California, Connecticut, and Georgia. Overall, the incidence of SE decreased 46% from 1996 to 1999. The greatest decrease was in Connecticut (71%), followed by northern California (50%), Minnesota (46%), and Oregon (13%). Although SE infection remains an important public health concern, there has been a remarkable decrease in its incidence. This decrease may be a result of targeted interventions, including on-farm control measures, refrigeration, and education efforts.

Female↗

PubMed2004

Hospitalizations and deaths due to Salmonella infections, FoodNet, 1996-1999.

Nontyphoidal Salmonella causes a higher proportion of food-related deaths annually than any other bacterial pathogen in the United States. We reviewed 4 years (1996-1999) of population-based active surveillance data on laboratory-confirmed Salmonella infections from the Emerging Infections Program's Foodborne Diseases Active Surveillance Network (FoodNet), to determine the rates of hospitalization and death associated with Salmonella infection. Overall, 22% of infected persons were hospitalized, with the highest rate (47%) among persons aged >60 years. Fifty-eight deaths occurred, for an estimated annual incidence of 0.08 deaths/100,000 population. These deaths accounted for 38% of all deaths reported through FoodNet from 1996 through 1999, and they occurred primarily among adults with serious underlying disease. Although Salmonella infection was seldom listed as a cause of death on hospital charts and death certificates, our chart review suggests that Salmonella infection contributed to these deaths.

Adult↗

PubMed2004

Epidemiology of sporadic Campylobacter infection in the United States and declining trend in incidence, FoodNet 1996-1999.

Campylobacter species are a leading cause of foodborne illness in the United States, but few population-based data describing patterns and trends of disease are available. We summarize data on culture-confirmed cases of Campylobacter infection reported during 1996-1999 to the Foodborne Diseases Active Surveillance Network (FoodNet) system. The average annual culture-confirmed incidence was 21.9 cases/100,000 population, with substantial site variation (from 43.8 cases/100,000 population in California to 12.2 cases/100,000 population in Georgia). The incidence among male subjects was consistently higher than that among female subjects in all age groups. The incidence trended downward over the 4 years, with incidences of 23.6, 25.2, 21.4, and 17.5 cases/100,000 population for 1996-1999, respectively--a 26% overall decrease. This trend was sharpest and most consistent in California. Overall, we estimate that ~2 million people were infected with Campylobacter in the United States each year during this time period. Although the number of Campylobacter infections appears to have decreased in the United States during 1996-1999, the disease burden remains significant, which underscores the need to better understand how the disease is transmitted.

Campylobacter↗

PubMed2004

Burden of self-reported acute diarrheal illness in FoodNet surveillance areas, 1998-1999.

To assess trends in the burden of acute diarrheal illness, the Foodborne Diseases Active Surveillance Network (FoodNet) conducted a population-based telephone survey during 1998-1999, using a random-digit-dialing, single-stage Genesys-ID sampling method. During the 12-month study period, 12,755 persons were interviewed; after the exclusion of persons with chronic diarrheal illnesses, 12,075 persons were included in the analysis; 6% (n=645) reported having experienced an acute diarrheal illness at some point during the 4 weeks preceding the interview (annualized rate, 0.72 episodes per person-year). Rates of diarrheal illness were highest among children aged <5 years (1.1 episodes per person-year) and were lowest in persons aged > or =65 years (0.32 episodes per person-year). Twenty-one percent of persons with acute diarrheal illness sought medical care as a result of their illness. Diarrheal illness imposes a considerable burden on the US population and health care system.

Acute Disease↗

PubMed2004

Epidemiologic issues in study design and data analysis related to FoodNet activities.

The Foodborne Disease Active Surveillance Network (FoodNet) seeks to determine and to monitor the burden of foodborne diseases in the United States more precisely and to attribute these diseases to specific food vehicles or other exposures. These objectives present statistical and epidemiologic challenges. Estimates of the burden of foodborne diseases should include an estimate of the uncertainty in such calculations. Monitoring the burden of foodborne diseases should account for the expansion of the FoodNet population over time. Attributing foodborne diseases to specific vehicles is facilitated by FoodNet case-control studies of sporadic illness. This article discusses the strengths and limitations of the various studies aimed at addressing these objectives in this supplement. Furthermore, because the FoodNet surveillance areas were not chosen specifically to reflect the demographic composition of the US population, this article also discusses the generalizability of FoodNet results to the US population.

Adolescent↗

PubMed2003

Outbreak of Shiga toxin-producing Escherichia coli O111:H8 infections among attendees of a high school cheerleading camp.

Few US clinical laboratories screen stool specimens for Shiga toxin-producing Escherichia coli (STEC) other than E. coli O157. An outbreak of STEC O111:H8 infections indistinguishable from E. coli O157:H7 at a youth camp highlights the need to improve non-O157 STEC surveillance. Interviews of 521 (80%) of 650 attendees revealed 55 (11%) were ill; 2 developed hemolytic-uremic syndrome. Illness was associated with consuming salad during the camp's first lunch meal (hazard ratio [HR], 4.68; P<.01), consuming ice provided in barrels on the camp's final day (HR, 3.41; P<.01), eating cob corn (HR, 3.22; P<.01), and eating a dinner roll (HR, 2.82; P<.01). Cultures of 2 of 11 stools yielded E. coli O111:H8. Results of serologic testing and additional stool cultures demonstrated no evidence of infection with other bacterial pathogens, including E. coli O157, and supported infection with E. coli O111. Clinical laboratories should routinely screen suspect specimens for non-O157 STEC and should serotype and report Shiga-positive isolates.

Adolescent↗

PubMed2002

A waterborne outbreak of Escherichia coli O157:H7 infections and hemolytic uremic syndrome: implications for rural water systems.

In the summer of 1998, a large outbreak of Escherichia coli O157:H7 infections occurred in Alpine, Wyoming. We identified 157 ill persons; stool from 71 (45%) yielded E. coli O157:H7. In two cohort studies, illness was significantly associated with drinking municipal water (town residents: adjusted odds ratio=10.1, 95% confidence intervals [CI]=1.8-56.4; visitors attending family reunion: relative risk=9.0, 95% CI=1.3-63.3). The unchlorinated water supply had microbiologic evidence of fecal organisms and the potential for chronic contamination with surface water. Among persons exposed to water, the attack rate was significantly lower in town residents than in visitors (23% vs. 50%, p<0.01) and decreased with increasing age. The lower attack rate among exposed residents, especially adults, is consistent with the acquisition of partial immunity following long-term exposure. Serologic data, although limited, may support this finding. Contamination of small, unprotected water systems may be an increasing public health risk.

Adult↗