Dorothy E. McComb

775 PROSPECTIVE STUDY OF MATERNAL AND INFANT INFECTION WITH CHLAMYDIA TRACHOMATIS

We examined endocervical and serum specimens from 322 pregnant women for C. trachomatis and for chlamydial antibody. Only 6(2%) of the women were infected with C. trachomatis. Chlamydial antibody was present in the genital secretions and serum of 47% and 73% of the women, respectively. Five infants born to the infected women and 89 control infants were followed for six months Four of 5 infants born to infected women harboured C.trachomatis Two developed culture positive conjunctivitis; two had nasopharyngeal carriage with upper respiratory symptoms but without pneumonia. One of 89 control infants developed asymptomatic nasopharyngeal carriage. Most (87%) of the infants had chlamydial antibody in the serum. Sixteen (18%) and 23(26%) of the 89 control infants had chlamydial antibody in their tears and nasopharyngeal secretions, respectively. All were asymptomatic; none developed clinical conjunctivitis or pneumonia.These data indicate that there is a high rate of transmission of C.trachomatis from mother to infant and post-natal acquisition of chlamydial infection is unusual. The high prevalence of serum and local antibody to chlamydia in our population coupled with the low rate of recovery of the organism in the mothers and the low incidence of disease in their infants, suggests that chlamydial antibody may be protective.