Adolescent Vaccine

Introduction and Rationale

• Definition: Adolescence is defined by the World Health Organization (WHO) as the period between 10 to 19 years of age.
• Epidemiological Significance: India has the largest adolescent population globally, necessitating targeted preventive healthcare interventions.
• Rationale for Vaccination:
  • Waning Immunity: Decline of protective antibody titers from primary childhood immunization (e.g., Diphtheria, Pertussis).
  • Epidemiological Shift: Improved sanitation has shifted the incidence of certain diseases to older age groups, increasing the risk of severe manifestations (e.g., Hepatitis A, Varicella).
  • Newer Exposures: Onset of sexual activity increases susceptibility to sexually transmitted infections (e.g., Human Papillomavirus, Hepatitis B).
  • Future Progeny Protection: Immunization against Rubella prevents Congenital Rubella Syndrome in future pregnancies.
  • Catch-up Opportunity: Provides a safety net for those who missed the primary immunization series during childhood.

Indian Academy of Pediatrics (IAP) Recommendations

The IAP Advisory Committee on Vaccines and Immunization Practices (ACVIP) categorizes adolescent vaccines into three distinct groups:

Routine / Mandatory Vaccines

These are universally recommended for all adolescents to maintain baseline herd immunity and personal protection.

• Tdap (Tetanus, Diphtheria, Acellular Pertussis):
  • Indication: Replaces the traditional Td or TT vaccine to address the resurgence of pertussis in older age groups.
  • Schedule: Single dose of Tdap at 10 to 12 years of age.
  • Catch-up: If missed, one dose of Tdap can be given at any time, followed by Td boosters every 10 years.
• Human Papillomavirus (HPV) Vaccine:
  • Indication: Primary prevention of cervical, vaginal, vulvar, and anogenital cancers, as well as genital warts.
  • Primary Target: Females aged 9 to 14 years. Catch-up is permitted up to 26 years. Can also be offered to males.
  • Preparations: Bivalent (HPV2), Quadrivalent (HPV4), and Nonavalent (HPV9 - preferred).
  • Schedule (9 to 14 years): 2 doses administered at 0 and 6 months.
  • Schedule (15 years and above, or immunocompromised): 3 doses administered at 0, 1 to 2, and 6 months.

Catch-Up Vaccines

Indicated for adolescents who have not completed their primary immunization series.

• Measles, Mumps, and Rubella (MMR):
  • Schedule: If completely unimmunized, 2 doses at an interval of 4 to 8 weeks. If 1 previous dose was given, administer 1 catch-up dose. Highly prioritized for females.
• Hepatitis B:
  • Schedule: For unvaccinated adolescents, a 3-dose series at 0, 1, and 6 months.
• Hepatitis A:
  • Schedule: 2 doses of inactivated vaccine (at 0 and 6 months) or a single dose of live attenuated vaccine. Prior serological testing (Anti-HAV IgG) is often considered cost-effective in endemic countries like India.
• Varicella:
  • Schedule: For those with no reliable history of clinical chickenpox or prior vaccination, 2 doses administered 4 to 8 weeks apart.
• Typhoid:
  • Schedule: Single dose of Typhoid Conjugate Vaccine (TCV) if not received previously.

Vaccines for Special Circumstances / High-Risk Groups

Targeted towards adolescents with specific underlying medical conditions, lifestyle risks, or travel requirements.

• Pneumococcal Vaccine (PCV followed by PPSV23):
  • Indications: Functional or anatomic asplenia (e.g., Sickle cell disease), HIV, chronic renal/cardiac/pulmonary disease, cochlear implants, CSF leaks.
• Meningococcal Vaccine (MenACWY Conjugate):
  • Indications: Terminal complement deficiencies, functional/anatomic asplenia, travel to endemic zones (e.g., Hajj, sub-Saharan Africa), and hostel/dormitory residents.
• Influenza Vaccine:
  • Indications: Annual administration for those with chronic respiratory conditions (e.g., severe asthma), hemodynamically significant cardiac disease, or immunosuppression.
• Rabies (Pre-exposure Prophylaxis):
  • Indications: High risk of unprovoked animal bites (e.g., veterinary handlers, certain geographic locations). Schedule involves days 0, 7, and 21 or 28.
• Japanese Encephalitis (JE) / Cholera / Yellow Fever:
  • Indications: Driven by regional endemicity and international travel protocols.

National Programs and Implementation Challenges

• Universal Immunization Programme (UIP): Currently provides Td at 10 and 16 years. Introduction of the HPV vaccine through a phased national rollout from Feb 28, 2026.
• Challenges in India: High out-of-pocket expenditure for newer vaccines (HPV, Tdap), lack of awareness among parents, poor health-seeking behavior in otherwise healthy adolescents, and the lack of a dedicated adolescent healthcare delivery platform.
• Strategies for Optimization:
  • Integrating comprehensive immunization drives into the School Health Program.
  • Leveraging Adolescent Friendly Health Clinics (AFHCs) under the Rashtriya Kishor Swasthya Karyakram (RKSK).
  • Opportunistic screening and vaccination during routine outpatient department (OPD) visits.