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United States Department of Agriculture

Agricultural Research Service

Research Project: CONTROLLING EGG CONTAMINATION WITH SALMONELLA ENTERICA BY UNDERSTANDING ITS EVOLUTION AND PATHOBIOLOGY Title: Is it time for NESST (National Egg Salmonella Surveillance Testing)?

Author
item Guard, Jean

Submitted to: Meeting Abstract
Publication Type: Other
Publication Acceptance Date: March 10, 2007
Publication Date: April 13, 2007
Citation: Bouldin, J.G. 2007. Is it time for NESST (National Egg Salmonella Surveillance Testing)?. Meeting Abstract.

Interpretive Summary: The logistics required for a National Egg Salmonella sampling Testing (NESST) project are described. Market egg sampling data has never been collected in the United States on a national basis and no regional sampling data has been collected in 10 years. Salmonella outbreaks continue to be attributed to eggs and no progress has been made in several years in decreasing incidence. Federal agencies such as FDA, CDC and FSIS have requested that better information is needed about the Salmonella microbial flora on shells and in the internal contents of whole shell eggs in order to make better decisions on how to decrease illness. Industry groups have explored conducting projects similar to NESST, but have not done so because of the cost and complexity. Because of an absence of institutional memory on how to conduct large scale sampling of the egg supply, information about labor, stream-lined culturing procedures, laboratory design and other logistics were collated. The budget to conduct NESST would exceed $2,500,000 in order to fund culturing at least 200,000 eggs processed in 6 egg batches. Plans included culturing both shells and contents, with 6 eggs per carton subjected to boiling for no longer than a minute to sterilize the shell and 6 eggs cultured without boiling. Eggs would be processed by placing eggs in quart paint cans, adding iron supplemented media, and using a commercial shaker to break eggs. At least 100,000 eggs per treatment group are required to determine the incidence of egg contamination within a statistically meaningful 90% confidence interval. Currently, USDA does not believe that this project is feasible given current budgets, limited extramural funding sources, and the existence of more pressing food safety issues such as attribution of illness to produce. However, information will be collated and placed on file with industry and vested government agencies to serve as a guideline for a NESST project if it is needed in the future to respond to national needs.

Technical Abstract: The logistics required for a National Egg Salmonella sampling Testing (NESST) project are described. Market egg sampling data has never been collected in the United States on a national basis and no regional sampling data has been collected in 10 years. Salmonella outbreaks continue to be attributed to eggs and no progress has been made in several years in decreasing incidence. Federal agencies such as FDA, CDC and FSIS have requested that better information is needed about the Salmonella microbial flora on shells and in internal contents of whole shell eggs in order to make better decisions on how to decrease illness. Industry groups have explored conducting projects similar to NESST, but have not done so because of the cost and complexity. Because of an absence of institutional memory on how to conduct large scale sampling of the egg supply, information about labor, stream-lined culuring procedures, laboratory design and other logistics were collated. The budget to conduct NESST would exceed $2,500,000 in order to fund culturing at least 150,000 eggs processed in 6 egg batches, which is a statistically determined number of eggs that would adequately access internal and external contamination. Plans included culturing both shells and contents, with 6 eggs per carton subjected to boiling for no longer than a minute to sterilize the shell and 6 eggs cultured without boiling. Currently, USDA does not believe that this project is feasible given current budgets, limited funding sources, and the existence of more pressing food safety issues such as attribution of illness to produce. However, information will be collated and placed on file with industry and vested government agencies to serve as a guidline in case a NESST project is needed in the future to respond to national needs.

Last Modified: 12/24/2014