Initial Acquisition of Mutans Streptococci by Infants: Evidence for a Discrete Window of Infectivity

Abstract

Oral bacterial levels of 46 mother-child pairs were monitored from infant birth up to five years of age so that the acquisition of mutans streptococci (MS) by children could be studied. The initial acquisition of MS occurred in 38 children at the median age of 26 months during a discrete period we designated as the "window of infectivity". MS remained undetected in eight children (17%) until the end of the study period (median age of 56 mo). The levels of both MS and lactobacilli in saliva of mothers of children with and without MS were not significantly different. Comparisons between a caries-active cohort colonized by MS (nine of 38) and children without detectable MS revealed similar histories in terms of antibiotic usage, gestational age, and birth weight. Interestingly, half of the children between the ages of one and two years who were not colonized by MS were attended by caretakers other than the mother, while all of the caries-active children during this same time period were cared for by their mothers; the difference was statistically significant. Here we report for the first time that MS is acquired by infants during a defined period in the ontogeny of a child. Support for the notion of a discrete window of infectivity comes from other sources, including animal models.

Associations between salivary bacteria and reported sugar intake and their relationship with body mass index in women and their adolescent children

“…Oral bacteria colonisations are transmitted from mother to child in early childhood [45][46][47] , but we do not know to what extent this has any effect at the age of 17. We did find a concordance in the prevalence of MS, but not in LB, between mother and son, but we cannot distinguish bacterial transmission from genetic predisposition and, most importantly, from inherited eating habits.…”

Longitudinal study of dental caries incidence associated with Streptococcus mutans and Streptococcus sobrinus in pre-school children

“…Straetemans et al (1998) suggested that a delayed acquisition of mutans streptococci may reduce the incidence of caries in both primary and permanent dentition later on. Further, acquisition of the organisms has been suggested to occur during a discrete age interval, termed the window of infectivity, between 19 and 31 months of age, during which the proportion of children with mutans streptococci was found to increase from 25 % to 75 % (Caufield et al, 1993;Köhler & Andréen, 1994). Thus, it is of great importance to detect the presence of these organisms in early childhood for dental caries prediction and subsequent treatment, as S. mutans and S. sobrinus are regarded as the main initiator microorganisms of the disease, with lactobacilli and others participating in its progression.…”

Dental Hygiene Participation in Managing Incipient and Hidden Caries

“…In particular, the patient at-risk for hidden and incipient caries needs to understand two important features of biofilm, one of which is the infectious potential of dental biofilm. Parents and caregivers may be surprised to learn that there is evidence of matrilineal transmission of mutans streptococci in infancy and early childhood [14,19]. Therefore, the presence of caries in the mother and in siblings can increase the risk for caries in children.…”