AURORA, Colo. -- Health officials said they have found a second E. coli infection in a child who attended an unlicensed home day care center in Aurora, but they say she's expected to recover and doesn't need treatment.

Last week, a 3-year-old boy who attended the same center died from E. coli.

Dr. Richard Vogt, director of the Tri-County Health Department, said the new case is in a 1-year-old girl.

Health officials have been testing other children who attended the center since the 3-year-old died. Vogt said he expects to find more cases because other parents have reported their children had mild gastrointestinal illnesses.

"Anything that's highly infectious can get easily transported in a day care center just because of all the environmental situations like diapers and the necessity of keeping things clean," Vogt said. "Sometimes an individual will succumb with their illness or have very severe complications and have real problems. That's the rarity."

Vogt said that officials may not be able to pinpoint the source of the bacteria. E. coli typically originates from the mishandling of meat and after the bacteria is in the body, it's transmitted when people don't wash their hands after using the bathroom.

The facility was unlicensed and had been for several years, according to health officials. The Colorado Department of Human Services issued a cease and desist order to the day care owner.

Parents of children who attended day care will be required to have children tested for E. coli and they must receive two negative tests before they can enroll their children anywhere else.

The children are being tested multiple times since it may take days or even weeks for the bacteria to present itself.

The day care's name and address have not been made public.