Introducing pentavalent vaccine in EPI in India: A counsel for prudence in interpreting scientific literature Author's response
Indian J Med Res 133, May 2011, pp 560-563
Sir,
We thank Gupta et al1 for responding to our editorial. Perhaps they have written the letter before the correspondences of Drs Madhavi & Raghuram2, Drs John & Muliyil3 and our response appeared in print.
All their questions have been answered in response to the letters above and we will be hard pressed to answer these questions without simply repeating ourselves.
The points they make are:
1. We should not have used under-2 morbidly statistics on the under 5 population.
The answer is available in Reference 3. In brief, we did this to show that even after the figures were exaggerated in this manner it still did not come up to the projections of the UNICEF.
2. The Vellore study4 cannot reflect community morbidity as parents’ exercised choice of taking or not taking treatment (notwithstanding the 2-weekly visits by the study teams). Some patients may have died before coming to hospital.
We have addresses this question in Reference 3. Verbal autopsies were done of all deaths at home precisely to overcome the problem of missing deaths at home.
3. The correspondents1 make their own estimates from other studies like the Million Death Study.
As these were not referred to in our editorial and they do not pertinent, we will not discuss the merits of their assumptions in this letter.
4. With regard the Bangladesh ‘probe like’ study5, the correspondents think that although the end-point for study was to be measured after 3 doses of vaccine (and there was no benefit), it is appropriate to present effectiveness with 2 doses without using appropriate statistical tests for multiple testing. We respect their right to have their opinion, although it is at variance with standard teachings of statistics.
5. They write that the Cochrane review only concluded “we could not conclude that the immune response elicited by the combined vaccine was different from or equivalent to the separate vaccines”. We refer to the next sentence in the authors’ conclusions of the Cochrane review for an explanation. They say “The data showed significantly less immunological response for H influenza and hepatitis B, and more local reactions to the injections”.
6. The equity argument was addressed in our responses earlier3. If the vaccine provides no protection as seen from the Bangladesh study, then it is important that resources are not squandered on the programme. The poor need equity in a number of areas but they do not seek equity in terms of being injected with worthless vaccines.
References
Gupta M, Prinja S, Kumar D, Kumar R. Introducing pentavalent 1. vaccine in EPI in India: A counsel for prudence in interpreting scientific literature. Indian J Med Res 2011; 133 : 560-3.
Madhavi Yy, Raghuram N. Pentavalent & other new combination 2. vaccines: solutions in search of problems. Indian J Med Res 2010; 132 : 456-7.
John TJ, Muliyil J. Introducing pentavalent vaccine in EPI in 3. India: Issues involved. Indian J Med Res 2010; 132 : 450-5.
Minz S, Balraj V, Lalitha MK, Murali N, Cherian T, 4. Manoharan G, et al. Incidence of Haemophilus influenzae type B meningitis in India. Indian J Med Res 2008; 128 : 57-64.
Baqui AH, El Arifeen S, Saha SK, Persson L, Zaman K, 5. Gessner BD, et al. Effectiveness of Haemophilus influenzae type B conjugate vaccine on presention of pneumonia and meningitis in Bangladesh children: a use control study. Pediatr Infect Dis J 2007; 26 : 565-71.