A food distributor located in New Jersey may be the root of the E. coli infection affecting Taco Bell customers in Northeastern states.

The New Jersey Department of Health and Senior Services is recommending that all Taco Bells in the Garden State receiving food from the McLane Foodservice, Inc. of Burlington discard all current food supplies and clean and sanitize their facilities in response to the E. coli outbreak that has sickened nearly four dozen people in three states.

A Taco Bell spokeswoman said the company had no immediate comment on whether the taco chain plans to comply with the recommendations at this time, adding that they are waiting to review all the facts.

Non-meat ingredients of Taco Bell menu items are under close scrutiny by state and federal investigators trying to pinpoint the cause of the outbreak.

Taco Bell ordered scallions removed from its 5,800 U.S. restaurants Wednesday after tests by an independent lab found three samples of green onions appeared to have a dangerous strain of the bacterium.

"In an abundance of caution, we've decided to pull all green onions from our restaurants until we know conclusively whether they are the cause of the E. coli outbreak," said Greg Creed, president of Irvine, Calif.-based Taco Bell.

Later Wednesday, the U.S. Food and Drug Administration said it is gathering samples of all non-meat items served in the restaurants that could carry the pathogen and planned to test them at FDA laboratories. The items include cilantro, cheddar cheese, blended cheese, green onions, yellow onions, tomatoes and lettuce, the FDA said.

California is the nation's largest supplier of green onions. But by December, as winter sets in, the vegetable is typically imported from Mexico.

Tainted green onions from Mexico were blamed for a 2003 outbreak of hepatitis A in western Pennsylvania that was also traced to a Mexican restaurant. Four people died and more than 600 people were sickened after eating the green onions at a Chi-Chi's.

At least 46 confirmed cases of E. coli sickness linked to Taco Bell have been reported in New Jersey, New York and Pennsylvania. The FDA said late Wednesday that there are also possible cases in Delaware and Connecticut.

All 15 Taco Bell restaurants in Philadelphia voluntarily closed Wednesday following a recommendation by the city's Department of Public Health.

Two restaurants on New York's Long Island were also closed Wednesday for cleaning. The chain had reopened other restaurants there linked to the outbreak. A Taco Bell in South Plainfield, N.J., also remained closed for cleanup.

At least five people in the three states remained hospitalized, including an 11-year-old boy in stable condition with kidney damage. New Jersey's health commissioner has said the most recent case of E. coli was reported Nov. 29, so the danger of infection appears to have passed.

E. coli is found in the feces of humans and livestock. Most E. coli infections are associated with undercooked meat. The bacteria also can be found on sprouts or leafy vegetables such as spinach. The germs can be spread by people if they do not thoroughly wash their hands after using the bathroom.

E. coli, or Escherichia coli, is a common and ordinarily harmless bacteria, but certain strains can cause abdominal cramps, fever, bloody diarrhea, kidney failure, blindness, paralysis and death.

Earlier this year, three people died and more than 200 fell ill in an E. coli outbreak that was traced to packaged, fresh spinach grown in California.

RBC Capital Markets analyst Larry Miller said the outbreak could affect Taco Bell sales in the short term. "It will take time for consumers to get confidence back, but it will come back," he said.

Taco Bell established a telephone number, 1-800-TACO BELL, for those with concerns about the outbreak.

The Associated Press and Reuters and FOXNews.com's Megan Dowd and Alexander B. Duncan contributed to this report.