Types of Vaccines in the National Immunization Schedule (NIS) – India
The National Immunization Schedule protects children against multiple preventable diseases through age-appropriate vaccinations. Key vaccines include:

BCG (Bacille Calmette-Guérin): Prevents tuberculosis; given at birth, provides long-term protection against severe forms such as miliary TB and TB meningitis.

Hepatitis B (Hep B): Prevents hepatitis B virus infection; administered at birth, six weeks, and 14 weeks.

Oral Polio Vaccine (OPV)/Inactivated Polio Vaccine (IPV): Prevents poliomyelitis; OPV given at birth and at multiple intervals during infancy, while IPV is included to minimize the risk of vaccine-associated paralytic polio.

Pentavalent Vaccine (DPT-HepB-Hib): Protects against Diphtheria, Pertussis, Tetanus, Hepatitis B, and Haemophilus influenzae type b; administered in three doses at six, ten, and 14 weeks.

Rotavirus Vaccine: Prevents rotavirus diarrhoea; given in two or three doses depending on the formulation.

Pneumococcal Conjugate Vaccine (PCV): Prevents pneumonia, meningitis, and invasive pneumococcal diseases; given in multiple doses during infancy.

Measles-Rubella (MR)/MMR: Prevents measles, rubella, and mumps; given at nine months and 15 months.

Japanese Encephalitis (JE): Provided in endemic areas; protects against viral encephalitis.

DPT Booster: Reinforces immunity against diphtheria, pertussis, and tetanus.

Tetanus and adult Diphtheria (Td): Given to adolescents and adults for tetanus and diphtheria prevention.

Adverse Events Following Immunization (AEFI)
An AEFI is any undesirable medical event after vaccination, whether or not causally related. Mild events are common, while severe reactions are rare.

Examples:

DPT: Pain, swelling, low-grade fever; rare—seizures, hypotonic-hyporesponsive episodes, anaphylaxis.

MMR: Fever, mild rash; rare—thrombocytopenia, transient encephalopathy.

OPV: Rare—vaccine-associated paralytic poliomyelitis (~1 in 2.7 million).