A month ago, the US Centers for Disease Control (CDC) reported that 22 people contracted salmonella infections from consuming US-raised eggs. Last week, the health organization updated that list to include 13 more cases, spread across eight eastern seaboard states and Colorado. Virginia and New York, with eight cases each, have been the worst-hit states.

The US Food and Drug Administration traced the outbreak to a farm in Hyde County, North Carolina, which is part of of Rose Acre Farms, which claims to be the second-largest supplier of eggs in the country and is headquartered in Indiana. In April, the company issued a recall of more than 206 million eggs.

“We have already implemented numerous remedial actions and have not only corrected deficiencies at the farm, but we’ve also taken other steps to ensure the farm meets or exceeds the standards by the FDA and USDA [US Department of Agriculture],” the company said in a statement sent to the Washington Post (paywall). That includes establishing a “corporate sanitation manager,” the Indiana Star reports, to, presumably, oversee sanitation and hygiene practices at the company’s farms (in addition to the representatives from the USDA that were already monitoring production on location).

Rose Acre has a history of salmonella outbreaks. In 1990, 450 cases across the US were linked to three Rose Acre farm sites. The USDA tried to stop the company from distributing eggs from the three contamination sites, which prompted a 19-year legal battle that ended when the case was dismissed by the Supreme Court in 2009.

Unrelated, a year later in 2010, the largest salmonella-related egg recall in the US occurred; after the FDA traced the outbreak—which sickened 1,500 people—to Iowa-based Quality Eggs, the agency forced a recall of 550 million eggs.

Salmonella is a genus of bacteria that can spread through chicken droppings and can live on the inside of eggs or their shells. The bacteria can also survive on beef, poultry, fruits, and vegetables. In most cases, food poisoning caused by Salmonella bacteria—also called salmonellosis—isn’t life threatening. In fact, there are over a million cases of salmonellosis annually. However, the CDC warns that the can be fatal in especially old or young populations, or others who have compromised immune systems. No one has died from this particular outbreak, though 11 people have been hospitalized. The FDA recommends that Americans throw out any of the possibly contaminated eggs, and has a list of possibly contaminated packages which can be found here.