Multi-generational Transmission of Mutans Streptococci in Early Childhood Caries. Rahman JE*, Featherstone JDB, Zhan L, Hoover CI (University of California San Francisco, School of Dentistry, San Francisco, CA)
Purpose: To determine the extent of multi-generational (grandmother-mother, mother-child, and grandmother-grandchild transmission of mutans streptococci (MS) in early childhood caries (ECC) families where grandmothers provide significant childcare (≥20 hours/week).
Methods: Ten grandmother-mother-child triads (30 participants) were recruited using a questionnaire. All children (aged 3-6 years) had at least one active carious lesion. DMFS/dmfs scores were determined using WHO criteria, and saliva samples were obtained. Saliva samples were cultured on MSSB agar to enumerate and isolate MS. Ten MS colonies were randomly selected and propagated for arbitrarily primed-polymerase chain reaction (AP-PCR) typing using two primers (OPA-5 and OPA-13).
Results: MS were isolated from all subjects except one grandmother, who had no MS detected. There were no significant differences in log10 MS CFU/mL of saliva (4.4±1.6, 4.6±1.0, 4.8±1.0, for children, mothers, and grandmothers, respectively). There were significant differences (P<.05) in DMFS/dmfs scores between grandmother-mother, mother-child, and grandmother-child (DMFS/dmfs Mean±SD, grandmother: 55.3±21.8, mother: 15.4±8.3, child: 33.4±16.3). Fermentation tests were used to differentiate between S. mutans and S. sobrinus. AP-PCR results demonstrated a 30% transmission rate from mothers to children, and a 44% transmission rate from grandmothers to children. Of all genotypes found in children, 14 out of 22 (64%) genotypes were from neither grandmother nor mother, and therefore from an unknown source.
Conclusion: The results indicate transmission of MS between grandmother-mother, mother-child, and grandmother-grandchild in ECC families where the grandmother provides significant childcare. This provides evidence to support more broadly based family-oriented strategies to reduce transmission of MS and the incidence of ECC.
Research supported by the CSPD Foundation