In a letter received Tuesday by Jimmy John’s restaurant franchisees in Illinois, sandwich chain exec Jimmy John Liautaud asked that alfalfa sprouts be removed from menus as a precautionary measure because they may be the cause of an outbreak of Salmonella.

The Illinois Department of Public Health earlier announced that it had received reports of 46 people sickened since Nov. 1.  Liatuad indicated the number could be much higher.

“Approximately 88 people have gotten ill in 15 states,” he wrote. “Of those, 40 have been interviewed. Of those 40, 28 have eaten at Jimmy John’s. Of those 28, 25 have eaten sprouts.”

Liautaud said sprouts were tested at the company’s main supplier Friday and the results were negative for Salmonella. 

“We are working closely with the state and they are doing a darn good job in helping find the source,” said Liautaud.  “Again, no source has been found yet. This is a precautionary measure.”

On Wednesday, the state health department updated its report, saying that many of the people who became ill with Salmonella reported eating alfalfa sprouts at Jimmy John’s restaurants in 10 Illinois counties – Adams, Champaign, Cook, DuPage, Kankakee, Macon, McHenry, McLean, Peoria and Will.

The department said that since Nov. 1 it had received confirmed reports of 50 Illinois residents and one Wisconsin resident with Salmonella serotype I 4,5, 12,i- who ate at a Jimmy John’s.  Earlier reports, it added, included pending cases but the latest numbers are of confirmed Salmonella cases only.