Tdap Vaccine

1. What is the Tdap Vaccine?

  • The Tdap vaccine is a combination vaccine, that offers triple protection against three bacterial infections- Tetanus, Diphtheria and Pertussis with a single shot
  • Tdap vaccine is a reduced antigen content vaccine compared to DTaP vaccine6

2. Why is Tdap vaccination recommended during pregnancy?

  • Tdap vaccination during pregnancy, helps in protecting the newborn / young infants from neonatal pertussis6,7
  • Tdap vaccine when administered during pregnancy results in transfer of antibodies from mother to foetus. These antibodies offer protection during first few months of life when newborns are most vulnerable to pertussis disease and complications6,7
  • Newborns are too young to be protected by currently available vaccination schedules8

3. How is the Tdap vaccine different from the TT/Td vaccine currently given during pregnancy?

  • TT (Tetanus Toxoid) / Td ( Tetanus and Diphtheria Toxoid) vaccine protects both mother and newborn against tetanus and diphtheria. Tdap vaccine additionally protects against pertussis; especially in newborns through transplacental transfer of antibodies from mother to foetus9
  • Since June 2011, the Advisory Committee on lmmunization Practices (ACIP) & American college of Obstetricians and Gynaecologists (ACOG) recommended that pregnant women should receive single dose of Tdap vaccine during the pregnancy6

4. What is pertussis?

  • Pertussis is a highly contagious respiratory infection caused by the gram-negative bacterium Bordetella pertussis.10,11 lt is more commonly known as’whooping cough’10
  • Pertussis is transmitted through airborne droplets or direct contact with nasopharyngeal discharges from an infected person10,12
  • It affects people of all ages but in newborns /young infants it can lead to serious complications such as pneumonia and seizures and may lead to hospitalization or even death12,13

Newborns and young infants are at highest risk of complications

The highest rates of Pertussis-associated complications are reported in infants
2 months of age13











5. What is the incidence of neonatal pertussis?

  • Disease burden in the developing world is high, with the global incidence during 2019 reported as ‘145486 cases. 11875 cases of pertussis were reported from lndia14
  • Under-diagnosis and under-reporting of cases is likely,6l and it has been suggested that the true incidence of pertussis is at least three times higher than the official rgported rates. Black et al. reported that 16 million cases of pertussis occurred in 2008 worldwide, resulting in 195,000 deathsl5

6. Why are newborns at a higher risk of neonatal pertussis?

  • Newborn infants in lndia start their primary DTP vaccination series after 6 weeks of age.17 This leaves the newborns vulnerable to contract serious pertussis infections5,6
  • Mothers have been identified as the source of infection in -37% of neonatal pertussis cases and are the most common source of pertussis infection for newborn infants18

7. When is the optimal time during pregnancy to recommend Tdap vaccination?

  • Data suggests optimal time for Tdap vaccination is during 27-26 weeks of gestation as higher antibody levels are likely to be achieved in the foetus. The maternal antibodies in the foetus help protect the newborn until they begin their own DTP vaccination5,6
  • Several global and local authorities like ACOG (American College of Obstetricians and Gynecologists), RCOG (Royal College of Obstetricians and Gynaecologists), IAP (lndian Academy of Paediatrics) also recommend single dose of Tdap vaccine
    during 27-36 weeks of gestation6,17,19

8.Can the Tdap vaccine be recommended to pregnant women who have received TT vaccination in the same pregnancy?

  • Tdap vaccination can be considered instead of the second dose of tetanus toxoid3
  • A prospective study involving healthy Thai pregnant women(370 enrolled in yearApril 201S-September 2016), were offered Tdap vaccine between 26-36 weeks of gestation. Out of the 370, ninety-eight women received at least one extra dose of tetanus-containing vaccine during this current pregnancy (1 dose in 37 women, 2 doses in 60 women, 3 doses in 1 women)
  • No reported increase in the severity or duration of adverse events associated with the administration of an extra tetanus-containing vaccine was observed20