Addendum to the response of the Author - for the record

12 February 2013

In view of the interest and responses to the controversy raised by the deaths following immunization with Pentavalent vaccine in India, I would like to update the earlier response.

Intention of NTAGI to Study AEFI
Drs Phadke and Menon suggest that the NTAGI introduced Pentavalent vaccine in just two States, because “simultaneous nationwide rollout (would have been) logistically challenging.” In our response we referred to the minutes of the NTAGI meeting that stated its rationale quite explicitly. The minutes state clearly as follows: “As the vaccine has not been introduced in India, there is not enough data on vaccine safety therefore; vaccine should be initially used in the states with better AEFI management and surveillance systems to monitor the vaccine safety.”

In its 'Recommendations' the NTAGI states: “Pentavalent vaccine to be introduced in Immunization programme in the states of Tamil Nadu and Kerala. Thereafter, data may be reviewed after 1 year of introduction before expanding the vaccine into other states.”

It was not clear why the correspondents brought up the matter of the intentions of the NTAGI. This is easier to understand now that it is being stated that the deaths following vaccination are merely coincidental deaths. Like with hypothesis testing, if the intention of the NTAGI was to examine AEFI and subsequently it was found that 15 children died soon after immunization, it will be difficult to pass them off as mere coincidences.

Proof of Causal Relationship
The difficulty in establishing causality in these deaths also needs to be explained. In 1999 with rotavirus vaccine, when there was an increase in incidence of intussusceptions of 1 per 10,000 children immunized, the vaccine was pulled off the shelves voluntarily by the manufacturers. No one thought of asking for a re-challenge with vaccine, to prove that there was a causal relationship. Now, when 1 in 10,000 are dying following Pentavalent vaccine, we have people asking for proof of a causal relationship which literally will require the dead child to be resuscitated and then re-challenged with the vaccine again, to see if he will react in the same way.

The Myth of Pentavalent Safety in Private Practice
Another argument that is being brought up is that the vaccine has been used in private practice for many years and it has not caused AEFI.

The implication is that the vaccine itself is safe but the procedures employed in the public heath system are defective and they may be responsible for the many deaths.

There are several problems with this logic.
1. Firstly private practice doctors see a very limited number of cases. Only 1 in 10,000 children had a reaction. In all of Kerala, only 15 doctors who had prescribed the vaccine had children dying soon afterwards. So the vast majority of doctors in Kerala will say they have had no deaths from the vaccine. But that does not negate the fact that 15 children died.

2. Very often the deaths from vaccine in private practice are not recorded as AEFI. I am aware of one such death in February 2012 in Kollengode, Kerala in a private hospital. When I asked for a list of all children who had died following immunization with Pentavalent vaccine in Kerala (under the Right to Information Act (RTI) 2005), this child’s name was not included in the list sent to me. As I knew all the details of the death, I wrote to the public information officer. He then wrote to me that they had information on the death but they did not include it, as it was in private practice!

3. The convener of the Indian Academy of Pediatrics (IAP) Committee on Immunization, has also asserted that the vaccine has been used in the private market for about 10 years and so it was safe.

He stated that the IAP had conducted a study last January on the vaccine, across 1,000 pediatricians. Their responses showed that 80 per cent of those reviewed found the Hib vaccine was safe and over 40 per cent had not observed “untoward” side-effects.

This figure may have been provided to allay public anxiety but paradoxically, it is indeed alarming. It would appear that 20% pediatricians did not find Hib was safe. I hope this is not true.

I am aware that all the AEFI investigations into the 4 children who died last month may not have been completed as yet, and it is too early to jump to conclusions. In the meantime it may be prudent to be cautious about recommending this vaccine.

Competing interests: None declared

Jacob Puliyel, Pediatrician

St Stephens Hospital, Delhi

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