Childhood Vaccination: What Each Shot Prevents and When It Is Given
Vaccination is the single most effective preventive measure in child health, and the diseases it prevents have become unfamiliar precisely because it works. That unfamiliarity is also why the risks of the diseases are now underestimated relative to the risks of the vaccines.
What the main vaccines prevent
BCG. Given at birth. Protects infants against severe tuberculosis, particularly TB meningitis and disseminated TB. A small scar at the injection site is normal and expected.
Hepatitis B. Birth dose plus further doses. Prevents chronic hepatitis B, which leads to cirrhosis and liver cancer decades later. The birth dose is time-critical, ideally within 24 hours.
Oral polio vaccine and inactivated polio vaccine. Prevents poliomyelitis and its permanent paralysis. India was certified polio-free in 2014; continued vaccination is what keeps it that way.
Pentavalent vaccine, combining diphtheria, pertussis, tetanus, hepatitis B and Haemophilus influenzae type b. Diphtheria causes airway obstruction; pertussis, or whooping cough, is dangerous in young infants; tetanus is frequently fatal; Hib causes meningitis and pneumonia.
Rotavirus. Prevents severe diarrhoea and dehydration, historically a leading cause of infant hospital admission and death.
Pneumococcal conjugate vaccine. Prevents pneumonia, meningitis and bloodstream infection from Streptococcus pneumoniae.
Measles-Rubella or MMR. Measles is far from trivial: it causes pneumonia, encephalitis and a rare fatal late complication, and it suppresses immunity to other infections for months afterwards. Rubella in pregnancy causes congenital rubella syndrome with deafness, blindness and heart defects.
Typhoid conjugate vaccine. Protects against typhoid fever.
Vitamin A, given alongside, reduces mortality and prevents nutritional blindness.
Additional vaccines available privately or in some programmes include hepatitis A, varicella, influenza, meningococcal and HPV. HPV vaccination prevents cervical cancer and is most effective when given before any exposure, typically at ages 9 to 14.
The broad schedule
India’s Universal Immunisation Programme provides these free. The timing in outline:
- At birth: BCG, hepatitis B birth dose, OPV zero dose
- 6, 10 and 14 weeks: pentavalent, OPV, rotavirus, pneumococcal, with IPV at specified visits
- 9 to 12 months: measles-rubella first dose, vitamin A, typhoid conjugate, pneumococcal booster
- 16 to 24 months: measles-rubella second dose, DPT booster, OPV booster, vitamin A
- 5 to 6 years: DPT booster
- 10 and 16 years: tetanus and adult diphtheria booster
- Vitamin A every six months up to five years
Unlock More Content
Watch a short ad to continue reading the rest of this article for free.
Preparing your free unlock…
Exact timings are set by the national schedule and your paediatrician; follow the card you are given rather than a general article.
If doses are missed
A delayed schedule does not need to be restarted. Catch-up schedules exist for almost every vaccine and every age. Take the immunisation card to a clinic and ask for a catch-up plan. The common belief that a missed dose means starting again discourages many families from returning at all, and it is not true.
Normal reactions
- Pain, redness and swelling at the site for one to two days
- Low-grade fever for 24 to 48 hours
- Irritability, drowsiness or reduced feeding for a day
- A small nodule or, with BCG, a sore that ulcerates and scars over several weeks, which is expected
Manage with paracetamol at the correct weight-based dose, a cool compress, extra feeds and comfort. Routine prophylactic paracetamol before vaccination is not recommended, as it may slightly reduce the immune response.
When to seek medical attention
- Fever above 40 degrees
- Persistent inexplicable crying for more than three hours
- Seizure
- Unusual floppiness or unresponsiveness
- Difficulty breathing, swelling of the face or lips, or a widespread rash soon after vaccination, which suggests an allergic reaction
- Large swelling spreading beyond the limb
- Fever beginning more than 48 hours after the vaccine, which is more likely a coincidental infection and should be assessed on its own merits
Serious adverse events are rare and are monitored through a national surveillance system.
Common concerns, answered plainly
Does vaccination cause autism? No. The single 1998 paper that suggested it was found to be fraudulent and was retracted, its author struck off the medical register. Many large studies across millions of children have since found no association.
Is it safe to give several vaccines at once? Yes. An infant’s immune system handles vastly more antigens daily from ordinary life. Combination vaccines reduce the number of injections and visits without reducing effectiveness.
Can a child be vaccinated with a mild illness? Yes. A mild cold, low-grade fever or mild diarrhoea is not a reason to postpone. Moderate or severe illness is a reason to wait until recovery.
Is natural infection better? Natural measles, pertussis or polio confer immunity at the cost of the disease itself, including its risk of death and disability. That is not a reasonable trade.
My child was vaccinated and still got the illness. No vaccine is 100 percent effective, but vaccinated children who get the disease typically have a far milder course and fewer complications.
Practical points
- Keep the immunisation card safe and bring it to every visit. Photograph it as a backup
- Check that the correct vaccine and dose were recorded
- Ask when the next dose is due before you leave
- Children with chronic illness, prematurity, or on immunosuppressive treatment may need a modified schedule and additional vaccines; discuss this specifically
- Ensure the adults in the household are up to date too, particularly for pertussis around a newborn
This is general information. Follow the schedule given by your paediatrician or immunisation centre, and discuss any history of allergy or immune problems before vaccination.