The egg is one of nature’s most nutritious, economical and versatile foods. In the rare event that an egg contains bacteria, you can reduce the risk by proper chilling and eliminate it by proper cooking. With proper care and handling, the egg poses no greater risk than any other perishable food.
The inside of the egg had once been considered almost sterile, but recently a bacterial organism, Salmonella enteritidis, has been found inside some eggs. How the contamination occurs is still unclear, but scientists are working to find a solution to the problem.
Only a very small number of eggs might contain Salmonella enteritidis. Even in areas where outbreaks have occurred, tested flocks show an average of only two to three infected eggs out of each 10,000 eggs produced.
Conservative scientists liberally estimate that, across the U.S., only one out of every 20,000 eggs produced might contain the bacteria. The likelihood of your finding an infected egg is about 0.005% (five one-thousandths of a percent). At this rate, if you are an average consumer, you might encounter a contaminated egg once every 84 years.
If an egg does contain the organism, the numbers in a freshly laid egg probably will be small and, if the eggs are promptly and properly refrigerated, will not multiply enough to cause illness in a healthy person.
If an egg containing Salmonella has been kept refrigerated and someone who uses good hygiene practices serves it to you immediately after proper cooking, you will simply have a nutritious meal. If the egg has been improperly handled, though, you might experience the foodborne illness called salmonellosis. You could have symptoms of abdominal cramps, diarrhea, nausea, vomiting, chills, fever and/or headache within 6 to 72 hours after eating. The symptoms usually last only a day or two in healthy people but can lead to serious complications for the very young, pregnant women, the elderly, the ill and those with immune system disorders. Anyone who has had salmonellosis may pass along the bacteria for several weeks after recovering, but salmonellosis is seldom fatal. While the risk of getting salmonellosis is very small, there is no need to take chances because cooking kills Salmonella.
⚠️ Other types of microorganisms could be deposited along with dirt on the outside of an egg. So, in the U.S., shell eggs are washed and sanitized to remove possible hazards. ⚠️
What is being done about Salmonella in eggs?
The U.S. egg industry, the public health community and government agencies have been working diligently to deal with Salmonella enteritidis.
Egg industry programs start by keeping breeder flocks free of Salmonella. Ongoing research is dedicated to discovering how Salmonella enteritidis gets into flocks and how it might be blocked. The industry also uses strict quality-control practices and sanitation procedures all through production, processing and preparation. This includes testing chicks to be sure they are free of Salmonella, bio-security (such as washing and sanitizing not only the eggs, but facilities, too) and other measures. To block Salmonella enteritidis from multiplying in the egg in the rare event it is present, eggs are held at cool temperatures following packing and throughout transportation. Important, too, are industry education programs which encourage food preparers to use safe food-handling practices.
Along with state representatives, the U.S. Department of Agriculture (USDA) and the Food and Drug Administration (FDA) are developing new national standards with aim of reducing and eventually eliminating egg-related salmonellosis. The strategies will include a scientific, risk-based, farm-to-table plan covering production, processing, transport, storage, retail handling and delivery. The plan will also include education on the responsibilities of consumers, inspectors and food handlers at all levels.
All animal protein foods — dairy products, eggs, meat, poultry and fish provide a ready supply of both food and moisture for bacterial growth. These foods are perishable and should receive refrigeration, sanitary handling and adequate cooking. Lack of attention to these details can make any food a "hazardous" food.