Frequency of IgG Antibodies to Pertussis Toxin Antigen among Antenatal Women Attending a Tertiary Care Hospital in Hyderabad

Abstract

Introduction: Pertussis is a vaccine preventable disease. Recently the is a rise in number of cases of Pertussis in developed countries. Under Universal Immunisation Programme in India two doses of TT vaccine are administered. One dose at 5 months of gestation or as soon as detection of pregnancy and the other 4 weeks apart. American College of Obstetricians and Gynecologists recommends a dose of Tdap during pregnancy. CDC also recommends a dose of Tdap vaccine to all pregnant women between 27- 36 weeks of gestation. This study has been conducted to know the level of IgG antibodies against Pertussis toxin in antenatal women since there is a dearth of literature in this aspect. Materials & Methods: Blood samples have been collected from 91 Antenatal women attending outpatient department of Tertiary Care Hospital, Hyderabad after obtaining consent. Serum has been separated and stored at -200C. ELISA has been put up against Pertussis toxin and Serum Anti-Pertussis toxin IgG antibody levels were analysed. Results: A value of >30 IU/ml was accepted as potential protective concentration, 20 -30 IU/ml as borderline &<20 IU/ml as negative. We found that the percentage of protected, borderline and unprotected antenatal women respectively were 16.48%, 9.89% & 73.62% for anti PT. Discussion: Most pregnant women in this study demonstrated low anti PT IgG. This finding suggests that a significant number of women & newborn were susceptible to Pertussis. Conclusion: Our results explained the susceptibility for Pertussis among pregnant women and also newborn born to them & supported the requirement for a Pertussis booster vaccine during pregnancy along with Tetanus and Diphtheria which may provide passive seroprotection in newborns during first months of life decreasing severity of illness and providing seroprotection.