
- The first ever scientifically conducted vaccine trial was that of the Salk’s injectable polio vaccine, in 1954 – 55, which involved (nearly) two million school children randomized into two groups and conformed to the laid down rigorous principles of “randomized, controlled, double blinded trial”.
- While that much large sample and scientific rigor may not be required for the prospective COVID vaccines, keeping in view the emergent nature of the requirement, however, at least the basic scientific principles will need to be adhered to.
- The point which I would like to make is NOT regarding the safety, efficacy and effectiveness of the candidate vaccines, which in any case, will need to be demonstrated in the upcoming trials. What I would like to submit is that having a vaccine in the stores or pharmacy outlets is only a small part of the larger picture. The main issue is going to be the huge logistics efforts to ensure that those who need the vaccine the most, do actually get it. Unfortunately, these are the very sections of our population (and very large in proportion too) who just do not have the ability to pay for it. How will we deliver one dose (preferably two doses) of this injectable vaccine to 1350 Million Indians, majority of whom live in rural areas, urban slums or congested low-income urban housing colonies?
- Unarguably, we have a nice health infrastructure as far as delivery of vaccines to the population is concerned, in the form of a well established national Immunization program, linked with the primary health care system. However, won’t we be grossly interfering with the immunization of children under 2 years age if we divert all these resources towards a huge COVID vaccination campaign?
- Even if we are able to organize all the resources (at a massive cost, albeit) for the COVID vaccination, I visualize that it would take at least a year from now (i.e., by July 2021) at the earliest, for us to start the population vaccination. Now, in just past 2 to 3 months, the disease has been spreading pretty fast. This is evident by both, the increase in cumulative number of cases detected per lakh population (it has increased from (approximately) 4 per lakh population in beginning of May 2020 to almost 75 per lakh by now, as well as by increase in population level of sero-positivity, from 1% in April – May to 24% in June – July. Thus, we may already reach the level of protective herd immunity of 60% to 70% by July 2021. So, will we really need to spend all the huge amount of efforts on vaccination, which is not likely to start before July 2021 and by which time, we would have already reached a reasonably good level of protective herd immunity?
Covid vaccination programme should be augmented with rapid antibody test .only sero negative young population need to be given vaccination . However all vulnerable persons ie elderly and immune compromised must be immunised.The calculation of vaccine requirement ab inito can be for 30- 40% of population as the herd immunity would have set in by that time.
The blog seems to suggest that herd immunity will ultimately develop in the population before vaccination reaches the masses. However, so far no disease has been controlled by herd immunity through natural infections. Diseases with even higher R0 required an immunisation schedule.
A very analytical blog. The government can have a ‘risk approach ‘ to the issue of vaccination against COVID19 in India. There is no need to covering the entire population. Hopefully better testing would come up by then, only the vulnerable, high group need to be covered. Dr Rajvir has correctly expressed his concerns about the immunisation programme of the children which shouldn’t be put in jeopardy.