Health workers think they know what caused the E. coli outbreak that sickened at least 15 on Long Island and 71 nationwide. However, they say it wasn?t green onions.

The Centers for Disease Control (CDC) said Wednesday that Taco Bells across the country didn?t have to pull green onions from their menus after all. According to the CDC, it now believes shredded lettuce was most likely the source of the outbreak. Though the CDC believes lettuce may be the culprit, no tests have confirmed the information.

Taco Bell officials made sure that restaurants across the country sanitized their facilities. They also switched to a different food distributor to make sure the outbreak doesn?t occur again. The CDC will now try to find out the source of the lettuce, since it is sure the vegetable was contaminated before it reached restaurants.

Many Long Islanders say they won?t eat at any Taco Bell until the government is 100 percent sure what caused the outbreak.

Related Information:Taco Bell says its food is safe, despite E. coli strain found in Hempstead Strain of E. coli found on white onions at Hempstead Taco Bell