"We are and have been doing everything in our power to prevent a problem of this nature," said Arnie Riebli, a partner in Petaluma's Sunrise Farms, which produces a million eggs a day.

Protective measures include enclosed housing facilities to protect laying hens from contact with rodents or wild birds that can carry salmonella. There are regular visits by a veterinarian and frequent testing for the bacteria, he said.

"All of our hens see a doctor at least twice a year," Riebli said.

The federal Centers for Disease Control reports almost 2,000 illnesses were reported from May through July with the strain of salmonella linked to the eggs. That is about 1,300 more cases than usual.

The Egg Safety Center estimates roughly 1 in 20,000 eggs may be contaminated with salmonella, and "most consumers probably wouldn't come in contact with such an egg but 1 time in 84 years."

The center recommends thoroughly cooking eggs to kill any bacteria.

— Robert Digitale, The Press Demcorat