I have a question about vaccine boosters.

For example, if I didn't take my baby for all 3 Dtap vaccines at 2, 4 and 6 months recommended here

When the child is 4-6 years, would she just need only 1 Dtap then? Or all 4????

I mean, do boosters just prolong how long the vaccines last for from 2 months to 4 months old, then from 4 to 6, then for 4 months to 4 years, or is it like 1 big vaccine split into smaller doses and you need to get all the doses???

Also, I wonder about your personal opinion about vaccines, as it seems that that's a lot of vaccines for a baby under 1 year old!

Thank you,


ANSWER: Hi Lena,

Lot of vaccines...Yes!!
They help prevent lot of serious infections!!!

If your baby has missed DTaP vaccines at 2/4/6 months, and is now 4-6 years old, she would need 3 doses of DTaP at 0, 2, 6 months..."0" is the date of first dose of DTaP, 2nd dose 2 months after 1st dose and third dose 4 months after 2nd dose (i.e., 6 months from first dose).

Please also get your child vaccinated with other vaccines, in case she has missed them too: Vaccines prevent a large chunk of morbidity and mortality...

Please feel free to ask for any further clarification...

Best wishes,
Dr. Puneet Kumar,
Kumar Child Clinic, Dwarka,
New Delhi, India

+91-9818356846, +91-11-45535647  

---------- FOLLOW-UP ----------

QUESTION: Thank you for your reply,

What about all those cases when people get seriously sick or die after the shots?

And why does a newborn need a hep B shot right when its born, since I read hep B is hard to catch unless you are an adult who uses needles and sexually active?


Hi Lena,

I would answer your 2nd question (regarding Hepatitis B shot) first:

Hepatitis B infection is also spread trans-placentally (mother to fetus transmission: also called as "vertical transmission"). Hence, it is crucial that every baby gets Hepatitis B shot soon after birth to prevent this devastating infection.

Developed countries have almost eradicated vertically-transmitted hepatitis B infection, thanks to the vaccination (and other measures if mother is a known case of Hepatitis B). However, in many under-developed countries, scores of kids still suffer from this devastating infection, as many babies miss the birth dose (or even subsequent doses) of the vaccine.

Now, coming to your first question...

Its all about probability.

Vaccine (or in fact any medicine) is recommended only when the probability of benefit (protection from infection) far outweighs the risk of adverse effects. Serious adverse effects with recommended vaccines are extremely, extremely rare. This is in stark contrast the "service" given by the vaccines in preventing millions of serious infections and deaths, every year globally.

It is not that all vaccines that are available in market are recommended uniformly. Recommendations depend upon the risk:benefit ratio.

I can give many examples to help explain the point:

1. Typhoid vaccine is available in the USA, but is not recommended for routine use, since typhoid is rare in the USA. Since the risk of contracting typhoid fever in USA is very less, it is used only as a "traveller vaccine" (reccommended only to those who are travelling to endemic counties like those in South Asia (as the risk of contracting infection increases manifold in such situation). However, for the same reason, Typhoid vaccination is recommended for routine use in countries of South Asia: The shot is to be taken every 3 years!

2. Similar is the case with BCG caccine (for severe forms of tuberculosis), Yellow fever vaccine and some others.

3. Some vaccines are not even recommended for the whole country but only for endemic regions. For example, Japanese Encephatitis vaccine is recommended only in 115 (out of total 632) districts in India or those who are travelling to those areas.

4. Rabies vaccines are available globally, but are not recommended routinely for all, despite the fact that Rabies is 100% fatal. Why? Because only those who are exposed to rabies are at risk (after animal bites). Rabies vaccine is given mostly as post-exposure prophylaxis (after animal bite), EXCEPT in lab-workers, researchers, veterinarians, etc. who are because of occupation are at higher risk: In these people, vaccine is routinely recommended.

5. Rotavirus is an infection that almost universally affects children below 5 years of age that often requires hospitalization (the risk of contracing this form of diarrhea somehow doesn't reduce even with better sanitation). The vaccines that are available currently are known to be effective. However, risk of serious adverse effects is much more if the vaccine is started after 14 weeks of age, or the course is not completed by 32 weeks of age. hence, if a infant misses this vaccine at the right age (2 or 3 doses, depending upon the brand, starting at 6 weeks), the vaccine is NOT recommended (despite the fact that the vaccine is effective), since the risk of adverse effects is more that the benefit: the vaccine is NOT SAFE above the stipulated age.

I would like to explain the concept of probability by some different examples (outside the field of vaccinology).

1. We know that wearing a helmet while riding a bike and wearing a seat belt while in a car saves lives by reducing the risk of serious injuries in case of accident. However, rare cases are on record where use of these aids have increased the injuries (helmet broke: fragments increased head injuries): still helmets and seat belts are strongly recommended since the probability of protection far outweighs the probability of adverse effect...

Continuing with the example of risk and benefit vis-a-vis helmets/ seat belt: Please note that those at higher risk need additional protection (the same way as vaccines): Those participating in Formula-1 car races wear helmets in addition to seat belts, while that is not recommended for ordinary passengers....Those who are at very high risk of gun-shots etc (like political leaders) have bullet-proof (and even bomb-proof!!) cars: That is not usually required for ordinary risk is less.

2. Under most circumstances we are safer at home. Still we go out: putting our lives at risk!! We increase the risk further on riding an automobile...Still we take the risk...Since the risk of not coming back home is far less than benefit of going out!! Some (calculated) risks have to be taken in life to survive!!!

Please feel free to ask for any further clarification....

Best wishes,
Dr. Puneet Kumar,
Kumar Child Clinic, Dwarka,
New Delhi, India

+91-9818356846, +91-11-45535647  


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Dr. Puneet Kumar


I would be happy to answer general queries on prevention and treatment of ailments in newborn, infant, toddler, child or an adolescent. Needless to say, it will not be possible to answer any query that requires diagnosing, since it is not possible to examine a child online.


I have worked in various capacities (medical officer, resident, senior resident, consultant) in public as well as private sector in Pediatrics and Neonatology. Today, I have over 17 years of experience in the field.

Currently, I am running my own clinic (Kumar Child Clinic) in Dwarka, New Delhi and am attached to Lifeline Hospital, Dwarka as consultant pediatrics and neonatology. I am also developing my clinic website into a comprehensive child health/ parenting website (

(a) Chapter "National Immunization Schedule" in Frontiers of Social Pediatrics, Jaypee Publishers: 2nd edition, 2016. (b) Article, "All about Pertussis vaccines" in special issue of Indian Journal of Practical Pediatrics, July-Sept 2015 (c) Three chapters (DTP vaccines, Pneumococcal vaccines and Poliovirus vaccines) in "Textbook of Pediatrics for Post-graduates" First edition: 2015. (c) Chapter: "Alternative delivery methods of vaccines" in IAP textbook of Vaccines, First edition, 2014 (published by IAP/ Jaypee Brothers) (d) Special Article: "50 years of Immunization in India: Progress and Future" in January 2013 issue of Indian Pediatrics (e) Four chapters in "FAQ: Book on Vaccines and Immunization Practices" First edition, 2011 AND 2nd edition, 2015 published by Jaypee Brothers. (f) Three articles in special issue of Journal of Pediatric Sciences on “Controversies and Challenges in Pediatric Vaccination Today" in Sept, 2010. Co-edited the series also. (f) Regular column, “How do I treat” in Pediascene ( (g) Review article, “Role of Anti-Poliovirus Agents in Polio eradication and beyond” in Polio Pulse, April, 2008. (h) Chapter on “Acute Infectious Diarrhea” in Textbook of Infectious Diseases in Children. (An IAP Publication), 2007. 2nd edition in 2011. (i) Book-Review (IAP Pediatric Drug Formulary, 2004) in Pediascene, March 2005 ( ) (j) Case-report on Osteopetrosis. Jharkhand Journal of Pediatrics, Dec-2002.

After MBBS, I have done DNB residency in Pediatrics.

Awards and Honors
Winner of IAP practising pediatrician's quiz in 2001.

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