Taylor Farms announced late Friday that it was recalling iceberg lettuce that had been shipped to retailers in 27 states because it was potentially contaminated with cyclospora, a parasite that can cause severe illness, including vomiting, cramping and explosive diarrhea.

Although the investigation by the Centers for Disease Control and Prevention tied the parasite to lettuce that Taylor Farms shipped to Taco Bell in five states, the company’s recall notice suggests far broader distribution of potentially contaminated greens. The announcement listed eight brand codes but did not say what they stood for. The company did not immediately respond to questions about them on Saturday morning.

The recalled products were shipped starting June 29 through as recently as Thursday and have expiration dates through August third. The company said on social media that no Taylor Farms-branded salad kits were involved, but did not provide a list of the restaurants or grocers that may have sold its iceberg lettuce, which was also mixed with romaine in some products.

“At this time, Taylor Fresh Foods has not publicly provided distribution information or a list of customers who received the product that was voluntarily removed from the market,” the Food and Drug Administration said in its recall notice.

F.D.A. regulations do not require the company to do so, a source of frustration for food safety leaders.

“Food safety advocates have urged F.D.A. over the years to make this a requirement,” said Sandra Eskin, the executive director of Stop Foodborne Illness, an advocacy group. “Without this essential information, a recall is not going to be effective.”

She added: “The whole point is to quickly identify the product and make sure no one else eats it.”

States listed as part of the recall include Florida, Illinois, Texas, Pennsylvania, New Jersey, North Carolina, Missouri and others. The recall notice does not list California or New York, but it is unclear if Taylor Farms supplied lettuce to companies in states affected by the recall that then distributed it widely.

Sysco, the nation’s largest food distributor, said in an emailed statement Friday evening that it was withdrawing all iceberg lettuce products from Mexico in its supply chain at the request of Taylor Farms.

“We will continue to actively monitor the situation and work with regulators as needed,” the company said, adding that it stopped selling and distributing those Taylor Farms products on Thursday.

So far at least 1,645 people have fallen ill and 141 have been hospitalized, most of them after consuming the lettuce sent to Taco Bell, which said it has removed all of the lettuce from its restaurants. The C.D.C. made that determination through scientific detective work, starting with case reports about people who fell ill and tracking back to a common food source. The case count is likely to rise as the C.D.C. factors in the scope of the recall.

The United States is on track to have more cyclospora cases in 2026 than in any previous year. The agency said it is investigating more than 5,100 additional illnesses that may have been caused by the parasite, which is transmitted through food or water contaminated with feces.

On Thursday evening, Taylor Farms executives met with the White House and Food and Drug Administration to try to distance the company from the outbreak and air concerns about the official investigations into the outbreak.

On Friday, the company said the information the F.D.A. presented led it to remove its iceberg lettuce from the market. The company said its Mexican processing plant Taylor Farms de Mexico in Guanajuato was voluntarily removing all iceberg lettuce grown in central Mexico.

The F.D.A. is planning to inspect the Guanajuato facility in coming days to determine how the cyclospora parasite got on the lettuce and track it through the supply chain.

Alice Callahan contributed reporting.