Consumer News: Research finds possible origin of bacteria that causes tooth decay in children

The general belief in dentistry is that Streptococcus mutans, a bacteria known to cause cavities, is transmitted from a mother to her child. However, new research suggests exposure to the bacteria frequently comes from outside the home.

Most children share the bacterial strain with their mother. In a study presented at the American Society for Microbiology MICROBE research meeting June 17 in Boston, 72 percent of kids had one or more strains that were contracted outside of the family, most likely from other children. Twenty-three percent of the test subjects only shared a strain with a sibling or other child living with them in the home.

The research was done by Stephanie Momeni, a doctoral candidate in the Department of Biology at the University of Alabama at Birmingham.. The National Institute of Dental and Craniofacial Research provided funding for the study. Ms. Momeni assessed the S. mutans genome of 119 African-American children who had at least one household family member evaluated; 76 percent of those children had more than one other family member evaluated.

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