ATLANTA - For the first time, health officials reported that the AIDS virus can be spread by a mother prechewing her infant's food, a practice mainly seen in poor, developing countries.
Three such cases were reported in the United States from 1993 to 2004, government scientists said yesterday in a presentation in Boston at a scientific conference.
It's blood, not saliva, that carried the virus, because in at least two of the cases, the infected mothers had bleeding gums or mouth sores, according to investigators at the US Centers for Disease Control and Prevention.
CDC officials say more study is needed, but they are asking parents and caregivers with HIV not to prechew infants' food.
Health officials believe chewed-food transmission is rare in the United States, where such behavior is considered unusual. In some countries, mothers do it because they have no access to baby food or a means of pulverizing food for toothless infants.
"But even one case is too many," said the CDC's Dr. Ken Dominguez, who helped investigate the US cases.
The first involved a 15-month-old African-American boy in Miami, diagnosed in 1993. His greataunt was infected with HIV and prechewed food for the boy when he was between ages 9 months and 14 months.
Then a 3-year-old Caribbean-American boy was diagnosed in 1995, also in Miami. His HIVinfected mother had prechewed food for her son.
Still uncertain they had definitively connected the practice to the spread of HIV, the doctors wanted more evidence. It was years later, 2004, before they could confirm a third case. A 9-month-old African-American girl was diagnosed with HIV in Memphis. The mother began prechewing the girl's food when she was about 4 months old.
All three children were infected with HIV at a time they would have been teething and had inflamed gums. It may be that both a caregiver and a child must have wounds in their mouths for the virus to have a good chance of passing from one bloodstream to another, the investigators said.
In developing nations without other feeding options, any campaign against prechewing could be nutritionally harmful, said Kimberly Hagen at Atlanta's Emory Center for AIDS Research.