CONCORDANCE OF PORPHYROMONAS-GINGIVALIS COLONIZATION IN FAMILIES

Periodontitis is a widespread disease that appears to be due to a spec ific bacterial infection, Several species of bacteria have been invest igated as potential pathogens, and particularly strong evidence links the presence of Porphyromonas gingivalis with indicators of periodonti tis, Information concerning the transmission of P. gingivalis between human contacts may be important in determining risk factors for diseas e and developing preventive strategies. A few small studies have provi ded some evidence of transmission between related individuals, but no large-scale study of families that would reflect the typical transmiss ion of this pathogen in the population has been reported, The purpose of this study was to investigate the transmission of P. gingivalis wit hin randomly selected, extended families, The colonization status of 5 64 members of multigeneration families was determined, and the degree of concordance observed among members of these families was then compa red to that expected to occur based on the prevalence of colonization in the population studied, A PCR assay was used for detection of P. gi ngivalis, Concordance in colonization was more frequently observed wit hin entire families (P = 0.0000) and for spouses (P < 0.001), children and their mothers (P < 0.001), children and their fathers (P < 0.01), adults and their mothers (P < 0.005), and siblings (P < 0.05) than wo uld be expected if P. gingivalis were randomly distributed in the popu lation studied, Results showed that contact with an infected family me mber substantially increased the relative risk of colonization in thes e intrafamilial pairs, This indicates that P. gingivalis is commonly t ransmitted by contact with an infected family member.