According to the Physicians Committee for Responsible Medicine (PCRM), "About 70 percent of the calories in eggs are from fat, and a big portion of that fat is saturated. They are also loaded with cholesterol-about 215 milligrams for an large-sized egg."  The General Nutrition Center says, eating eggs may increase the risk of heart attacks, gallstones, diabetes, and other diseases.  Not only are all eggs full of saturated fat and cholesterol, but battery eggs have a higher fat content and risk of salmonella poisoning than naturally produced eggs.

Battery eggs expose consumers to greater levels of Salmonella.  Experiments have shown that force-molting, "significantly depressed the cellular immune responses [of the hens] and increased the severity of a concurrent intestinal Salmonella enteritidis infection (Davis, Karen, Prisoned Chickens, Poisoned Eggs, Summertown, TN: Book Publishing Company, 1996, p. 76). 

Every year more than 650,000 Americans are sickened from eating Salmonella-tainted eggs;  600 of them die. There was a 600 percent increase in Salmonella poisoning from raw or undercooked eggs between 1976 and 1986 (Barnard, Neal, The Power of Your Plate, Summertown, TN: Book Publishing Company, 1990, p. 165).

"Salmonellosis, or Salmonella food poisoning, from contaminated eggs has been a problem primarily in the northeastern states...  Authorities report a sixfold jump in the disease in nine northeastern states during the decade ending in 1986" (Animal Factories, p. 79).  But now illness caused by Salmonella is increasing in other parts of the country as well. "The practice of recycling manure, dead chickens, feathers, and condemned animal parts back into animals' feeds is believed to be spreading germs" (Mason, Jim and Singer, Peter, Animal Factories (rev. ed.), New York: NY: Harmony Books, 1990, p. 79).

The use of antibiotics in agriculture is part of another serious public health problem in the United States.  "Feed additives are the mainstay of factory productivity.  Antibiotics are the most widely used.  Each year, about fifteen million pounds of antibiotics go into animal feeds" (Animal Factories, p. 51).  Antibiotics are given to battery hens to control the bacterial diseases that thrive in crowded confinement, and to manipulate egg production.  For example, "virginiamycin is said to increase feed conversion per egg laid, bacitracin to stimulate egg production, and oxytetracycline to improve eggshell quality and extend the period of high egg production and improve feed efficiency in the presence of stress and disease" (Prisoned Chickens, Poisoned Eggs, p. 61). 

In the United States nearly 100 percent of laying hens are given antibiotics.  According to an article in Newsweek: "for sheer overprescription, no doctor can touch the American Farmer.  Farm animals receive 30 times more antibiotics that people do" (Begley, Sharon, "The End of Antibiotics," Newsweek March 28, 1994:8. cited in Prisoned Chickens, Poisoned Eggs, p. 61).

According to the Union of Concerned Scientists, as much as 70 percent of all antibiotics produced in the United States are fed to healthy livestock for "growth promotion." 

Not only does the overuse of antibiotics reduce their effectiveness in animals; it poses a real danger to humans.  For example, according to a New York Times article, Cipro is in danger of becoming a casualty of what might be called the post-antibiotic age. Bayer, the maker of Cipro, also sells a chemically similar drug called Baytril, which is used in large-scale poultry production worldwide.  The widespread use of Baytril in chickens has already been shown to decrease Cipro's effectiveness in humans for some types of infections.

"The overuse of antibiotics in animal agriculture has [also] caused the evolution of 'super' Salmonella and other toxic bacteria that resist antibiotic treatment in chickens, humans and other animals" (Prisoned Chickens, Poisoned Eggs, p. 61).
 

Avian influenza has killed multiple people in Hong Kong and Europe as recently as April 19, 2003.  This is a different strain of the same disease that 4.7 million hens in Connecticut are currently under quarantine for.  "The World Health Organisation said it was conceivable that [avian influenza] could turn into a human epidemic, just as an animal disease is believed to be the possible origin of the deadly Severe Acute Respiratory Syndrome (SARS) sweeping the globe" (source aol.com).