The US FDA and the CDC are widening their investigation ‌into a cyclosporiasis outbreak linked to shredded iceberg lettuce from central Mexico after identifying cases in four additional states.

This outbreak now includes cases from nine states: Illinois, Indiana, Kansas, Kentucky, Michigan, Ohio, Oklahoma, Pennsylvania, and West Virginia, the FDA said on ​Friday.

A total of 1,947 people infected with the cyclospora parasite, with exposure to Taco Bell, have ​been reported by the nine states, the FDA said, citing epidemiological data collected by ⁠CDC.

There have been at least 98 hospitalizations, and no reported deaths from the infection, the regulator said.

Oklahoma’s health ​department said it is working with the FDA to determine whether additional cases are tied to the outbreak.

Cases ​of cyclosporiasis have been reported in at least 41 states this year, though investigators are still working to determine how many cases are linked to the outbreak tied to shredded iceberg lettuce supplied by Taylor Farms and served at Taco Bell restaurants.

State ​health departments in Nebraska, Rhode Island, New Mexico and Maryland told Reuters they have not found evidence ​linking cyclosporiasis cases reported in those states this year to the recent multistate outbreak.

New Hampshire health officials confirmed nine cyclosporiasis cases ‌linked ⁠to recalled Taylor Farms lettuce served at Cheshire Medical Center’s cafeteria and are investigating additional potentially related illnesses.

Oregon’s health department said two residents developed cyclospora infections associated with the ongoing multistate outbreak. Both had recently traveled to states included in the nationwide recall of pre-shredded lettuce linked to the infections.

North Carolina health officials said the ​state’s rise in cyclosporiasis ​cases does not appear ⁠linked to the multistate Taco Bell outbreak, with parsley, cilantro and lettuce the most commonly reported exposures among patients.

Michigan, the hardest-hit state, reported 8,176 probable cases of the ​intestinal infection on Friday, up 532 from a day earlier.

On July 17, Taylor ​Farms recalled iceberg ⁠lettuce sourced from central Mexico. The recall includes lettuce sold in retail stores, served in restaurants and distributed to food service customers.

The FDA urged the public to continue to avoid all products listed in Taylor Farms’ recall.

Taylor Farms ⁠has temporarily shut ​down the Central Mexico processing facility that U.S. health officials have ​linked to the outbreak, an industry source familiar with the matter said on Thursday.