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.

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

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.

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.

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.

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.