Factors related to maternal transmission of mutans streptococci in high-risk children-pilot study.

PURPOSE: The purpose of this study was to investigate virulence factors associated with maternal transmission of mutans streptococci (MS). METHODS: Saliva samples were collected from 10 mothers with active caries and their 2- to 5-year-old children. Ten MS colonies were isolated from each subject. Transmission of MS was identified by arbitrarily primed polymerase chain reactions. Biofilm formation and mutacin production of the isolates against Streptococcus gordonii 10558, Streptococcus sanguinis 10557, Streptococcus mutans 25175, and Streptococcus sobrinus 6715 were analyzed. RESULTS: All mothers and children had MS colonization. Only 7 of the 36 maternal genotypes (33 Streptococcus mutans genotypes and 3 Streptococcus sobrinus genotypes) were transmitted. Maternal transmission was found in 4 mother-child pairs, whereas 9 children had nonmaternal genotypes. There was no difference in biofilm formation between transmitted and nontransmitted genotypes (P>.05). Transmitted genotypes, however, produced more mutacin against Streptococcus sobrinus 6715 than nontransmitted genotypes. CONCLUSIONS: This pilot study showed that there may be nonmaternal as well as maternal mutans streptococci transmission.