BENGALURU: Administration of the Pentavalent vaccine (PV) against Haemophilus influenza Type-B (Hib) and Hepatitis-B, has led to double the number of deaths of children compared to DPT (Diphtheria-Pertussis-Tetanus) vaccine according to a new study published in the peer-reviewed Wolters Kluwer Health’s Journal, a medical journal of Dr DY Patil University, Mumbai.
The study by Dr Jacob Puliyel, head of paediatrics at St Stephen’s Hospital, and Dr V Sreenivas, professor of biostatistics at All-India Institute of Medical Sciences, both in New Delhi, found there were 237 deaths within 72 hours of administering the Pentavalent vaccine (PV) — twice the death rate among infants who received DPT vaccine.
Extrapolating the data, the authors estimated that vaccination of 26 million children each year in India will result in 122 additional deaths within 72 hours, due to switch from DPT to PV. “There is likely to be 7,020 to 8,190 deaths from PV each year if data from states with better reporting — namely Manipur and Chandigarh — are projected nationwide,” their report says.
Karnataka reported three deaths due to pentavalent vaccine recently, two of which were due to sepsis, a lab in Kasauli (Himachal Pradesh) found. However, the cause of death report is awaited in the case of one other boy. The Union health ministry, in January this year, had ordered a study on the sudden spike in deaths following immunisation in 2017 to 1,139 from 176 in 2016 and 111 in 2015.
An adverse event following immunisation (AEFI) is any untoward medical occurrence which follows immunisation and which does not necessarily have a causal relationship with the usage of the vaccine. The adverse event may be any unfavourable or unintended sign, abnormal laboratory finding, symptom or disease.
Puliyel, Sreenivas and their colleagues undertook the study to find out if these deaths were merely coincidental or vaccine-induced.
The authors obtained data of all deaths reported from April 2012 to May 2016 under the Right to Information Act. Data on deaths within 72 hours of administering DPT and PV from different states were used.
HOW THEY WENT ABOUT THE STUDY
For their study, the authors assumed that all deaths within 72 hours of receiving DPT are natural deaths. Using this figure as the baseline, they presumed that any increase in the number of deaths above this baseline among children receiving PV must be caused by this vaccine.
If a state introduced PV in 2014, then data on DPT doses, PV doses and deaths following vaccination were noted from that year on. This ensured that the deaths were all reported from the state using the same surveillance system.
The authors 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, for example by protection against lethal diseases like Haemophilus influenza. Despite the data presented in the paper from a large cohort, the authors point out that the evidence is merely circumstantial and not conclusive. “These findings of differential death rates between DPT and PV do call for further rigorous prospective population-based investigations,” the study concluded.
Dr Pradeep Haldar, deputy commissioner, immunization division, ministry of health and family welfare, said, “We cannot comment on individual studies. Neither can we rely on AEFI data reported on HRMS the data for which is collated in the districts. Only that data that is validated by the AEFI National Committee can be considered as deaths caused by immunisation.”
WHAT IS PV?
PV is a combination of DPT vaccine and two more vaccines against Haemophilus influenza Type-B (Hib) and Hepatitis B. Starting December 2011, PV was introduced in India’s immunization programme to replace DPT vaccine in a staged manner with a view to adding protection against Hib and Hepatitis-B without increasing the number of injections given to infants.