Infant Deaths Following Vaccination Doubled In India After Pentavalent, Says Study

A new study says that the deaths of infants soon after vaccination have doubled since the Pentavalent vaccine (PV) was introduced in India six years ago, compared to the DPT (Diphtheria-Pertussis-Tetanus) vaccine that PV is replacing in a phased manner.

The DPT vaccine is a combined vaccine, administered to newborn babies at three stages, which protects against three infectious diseases — diphtheria, pertussis (whooping cough), and tetanus.

PV is a combination of DPT vaccine and two more vaccines against hepatitis B and Haemophilus influenza type B (Hib).

The study analysed data on deaths within 72 hours of administering DPT and PV from different states. It has called for a “rigorous review of the deaths following vaccination with PV”.

It was conducted by Dr Jacob Puliyel, Head of Pediatrics at St Stephens Hospital, Delhi and Dr V Sreenivas, Professor of Biostatistics at the All India Institute of Medical Sciences, Delhi.

PV was introduced in India’s immunization programme on 15 December 2011, meant to provide added protection against Hib and hepatitis B without increasing the number of injections given to newborns.

Supposed to replace DPT in a staged manner, it was introduced in two states (Kerala and Tamil Nadu) and then expanded to other states. However, DPT vaccine continues to be administered in many districts within the same state that have not been covered by PV yet.

On the first day itself that PV was introduced, the death of a baby was reported from Kerala. What followed were sporadic newspaper reports of unexplained deaths of infants following immunization with PV.

Dr Puliyel and Dr Sreenivas undertook the study to find out if these deaths were merely coincidental or induced by the vaccine. The study has been published in the Wolters Kluwer Health’s journal, the peer-reviewed medical journal of Dr D Y Patil University.

The authors obtained data of all infant deaths reported between April 2012 and May 2016 under the Right to Information Act.

For their study, the authors assumed that all infant deaths within 72 hours of receiving DPT were naturally occurring deaths due to the Sudden Infant Death Syndrome (SIDS).

The SIDS describes deaths among newborn babies that can occur without any apparent or explainable reason, associated only temporally to immunization but unrelated to vaccination. However, doctors say that such SIDS deaths are quite rare. The SIDS rate in India is not known.

Both PV and DPT are administered to babies at the same age (at 6 weeks, 10 weeks, and 14 weeks). In the districts in each state that were still administering DPT vaccine, the study looked at the deaths associated with DPT after PV was introduced in the state.

The hypothesis was that if there is a statistically significant increase in the rate of infant deaths after receiving PV as compared to the DPT that was being administered to other children in the same state, then the increased rate of deaths may have been caused by PV. The increase in the deaths then cannot be attributed to the natural rate of SIDS because the natural causes would already be subsumed under rate of deaths after DPT.

“Babies who are taken for vaccination are usually healthy. The death rate among infants is made up of children who are actually sick. So apart from the occasional deaths as part of SIDS, there is no reason for a healthy immunized baby to die soon after receiving vaccination,” said Dr Puliyel, speaking to Newsclick.

“If the deaths were due to SIDS, then the rate of deaths should have been similar among babies receiving DPT vaccine and those receiving PV.”

The study says that approximately 45 million infants received DTP vaccination while approximately 25 million were administered PV.

The death rate of infants after receiving DPT was 4.8 deaths per million but it doubled to 9.6 deaths per million among babies vaccinated with PV. While 217 infants died after DTP, 237 died following PV, and there were 4.7 additional deaths per million within 72 hours of being vaccinated with PV instead of DPT.

The authors extrapolate from the data to estimate that vaccination of 26 million children each year in India would result in 122 additional deaths within 72 hours, because of the switch from DPT vaccine to PV.

“There is likely to be 7,020 to 8,190 deaths from PV each year if data from states with the better reporting, namely Manipur and Chandigarh, are projected nationwide,” the report says.

The authors also note that while the study looks at the short-term increase in deaths (within three days of vaccination), it does not calculate the potential benefits of PV on infant mortality.

The study concludes that the differential between death rates with DTP and PV “call for further rigorous prospective population-based investigations.”