OBJECTIVE: To analyze data for 60 poultry flocks voluntarily enrolled in the Pennsylvania Salmonella enteritidis Pilot Project and determine management and environmental risk factors associated with production of S enteritidis-contaminated eggs. SAMPLE POPULATION: 60 flocks for which at least 1 environmental sample (manure or egg-handling equipment) was positive for S enteritidis. PROCEDURE: Samples of manure, egg-handling equipment, and mice were submitted for bacterial culture of S enteritidis. When S enteritidis was isolated from environmental samples, 1,000 eggs were collected from the flock every 2 weeks for 8 weeks and submitted for bacterial culture. RESULTS: 18 flocks were found to have produced contaminated eggs. Estimated overall prevalence of contaminated eggs was 2.64/10,000 eggs produced, but flock-specific prevalence ranged from 0 to 62.5/10,000 eggs. Flocks with high levels of manure contamination were 10 times as likely to produce contaminated eggs as were flocks with low levels. However, 5 flocks with low levels of manure contamination produced contaminated eggs. CONCLUSIONS: Evaluation of the level of manure contamination could be used to help identify flocks at risk of producing S enteritidis-contaminated eggs. CLINICAL RELEVANCE: Flocks with high levels of S enteritidis-contaminated manure appeared to pose the greatest public health threat, and on-farm programs to reduce the prevalence of egg contamination should be developed for farms with high levels of manure contamination. Efforts to reduce the overall number of on-farm pathogens should decrease the incidence of foodborne disease in humans.
OBJECTIVE: To analyze data for 60 poultry flocks voluntarily enrolled in the Pennsylvania Salmonella enteritidis Pilot Project and determine management and environmental risk factors associated with production of S enteritidis-contaminated eggs. SAMPLE POPULATION: 60 flocks for which at least 1 environmental sample (manure or egg-handling equipment) was positive for S enteritidis. PROCEDURE: Samples of manure, egg-handling equipment, and mice were submitted for bacterial culture of S enteritidis. When S enteritidis was isolated from environmental samples, 1,000 eggs were collected from the flock every 2 weeks for 8 weeks and submitted for bacterial culture. RESULTS: 18 flocks were found to have produced contaminated eggs. Estimated overall prevalence of contaminated eggs was 2.64/10,000 eggs produced, but flock-specific prevalence ranged from 0 to 62.5/10,000 eggs. Flocks with high levels of manure contamination were 10 times as likely to produce contaminated eggs as were flocks with low levels. However, 5 flocks with low levels of manure contamination produced contaminated eggs. CONCLUSIONS: Evaluation of the level of manure contamination could be used to help identify flocks at risk of producing S enteritidis-contaminated eggs. CLINICAL RELEVANCE: Flocks with high levels of S enteritidis-contaminated manure appeared to pose the greatest public health threat, and on-farm programs to reduce the prevalence of egg contamination should be developed for farms with high levels of manure contamination. Efforts to reduce the overall number of on-farm pathogens should decrease the incidence of foodborne disease in humans.
Authors: Gerald A Mumma; Patricia M Griffin; Martin I Meltzer; Chris R Braden; Robert V Tauxe Journal: Emerg Infect Dis Date: 2004-10 Impact factor: 6.883