Vaccination drive: Last mile is much harder ... requires community engagement, says Gagandeep Kang

India is within striking distance of the 100 crore vaccinations milestone. A mammoth roll-out journey over 10 months, involving healthcare workers, vaccine-makers and logistics companies, to mention just a few, have participated in this uphill task.

Looking at what lies ahead in terms of covering the tricky “last mile” of vaccine coverage, top scientist Dr Gagandeep Kang, professor with The Wellcome Trust Research Laboratory, Christian Medical College (Vellore), is optimistic. “We will get there at the rate we are going — but it will require much effort,” says Dr Kang, in an interview with BusinessLine.

How does one view India's 100 crore vaccinations in terms of the effort, organisation and supply?

It is fantastic. I think the government and the companies have done a great job. In particular, I am delighted that we finally have an adult immunisation programme — now that we know it can be done, I hope that we will use our learning from this programme for other vaccines as well. Influenza vaccines is one example, but immunization for the elderly can include other vaccines as well.

Could we have ramped up faster? Yes, of course, that would have been helpful in the early days, but the companies did face a lot of challenges, that they seem to have overcome now and we have a stable increasing supply.

While the standalone number is mammoth, in terms of coverage about  21 per cent of the population is fully vaccinated, compared to say China (the only comparable population) where close to 75 per cent is fully vaccinated. Your thoughts on this?

We will get there at the rate we are going — but it will require much effort. The last mile is much, much harder than the first. We need to identify areas where vaccination rates are low or where there are unreached or underserved populations and ensure that they also have high rates of coverage. This is going to be harder, and requires a lot of community engagement, but it needs to be done.

Even as countries grapple with vaccination, Japan seems to have caught up on its vaccination and reports suggest they are seeing their lowest cases yet, and are calling it a success story. What would you say of their experience?

Once Japan had access to a good number of vaccines, it was able to ramp up quickly. It took them a while to decide on the programme, but once they got going they were able to reach their population, which has a much greater proportion of the elderly, through their excellent public health system. Japan will need at some point to think of boosters for at least some parts of its population, but right now they are in a good place.

On the other side, Israel has gone in for boosters, too, and are saying it works - but wouldn't it be too early to call?

Israel vaccinated with high coverage very quickly, but then when the delta variant came in, their numbers, including of severe disease, started to climb, based on which they introduced a booster. The early fantastic results we saw from Israel in February are being repeated again now, but the difference is that the first time around the severe disease reduction was in a largely previously uninfected, unvaccinated population, whereas now it is the incremental benefit of the booster on decreasing, but not absent, protection —so in absolute numbers, much less benefit.

Recent reports from Sweden published in Lancet, where the AstraZeneca (AZ) vaccine was stopped in people younger than 65 years - shows an mRNA vaccine worked better as a second dose in boosting immunity. And that two AZ doses only had a 50 per cent efficacy against risk of infection. How should India, where Covishield (the AZ vaccine) is the large staple of vaccination, handle this information?

Risk of infection is not the same as risk of disease, and vaccines work better after disease than infection. I do not think that India needs to worry based on the Swedish data. We have had a large proportion of people naturally infected, much higher than in Sweden, and we know that the protection from a combination of vaccination and infection is much stronger against later infection and disease than protection from vaccination alone. So direct comparisons will be inaccurate.

In terms of using vaccines other than AZ, absolutely. We should be making every effort to have every platform available in India, because combinations may be our best option in the long run. But we need to do those studies and then make policy decisions based on evidence.

Finally on children's vaccines - immunisation of children is something India pulls off reasonably well and has been doing so for years now. So why is there a need to be more guarded in vaccinating children against Covid-19, given that there are two approved Covid vaccines ready for use in children?

It is very likely that we will ultimately need to vaccinate children, or at least subsets of children like adolescents. We also need to vaccinate children with co-morbidities, and we need to do that sooner rather than later. But the question is, do we have what are the best vaccines available for children? And is there sufficient data to use the vaccines that we do have?

Zy-CoV-D is a new platform for vaccines. Phase 3 trials show that it is safe and works in adults. 700 children got the vaccine and had no side-effects, but immunogenicity data from 10 children is enough. Are we ready to use this in children? I would prefer that we introduce the vaccine in adults first, get some experience and monitor safety.

In parallel, we should complete the ongoing study in children, generate more data, and also add a clinical trial for children with comorbidities. Safety is also monitored more closely in a clinical trial than in a programme. We can define the minimum data set needed to make a decision, and when that is generated, make a decision on how best to use the vaccine in healthy children and those with co-morbidities.

Covaxin has been in tens of millions of adult. Based on vaccine trials, it is safe and efficacious. We do not yet have effectiveness data that show us how the vaccine is performing in real life, but I hope that will happen soon. Nonetheless, there is worrying data about inactivated vaccines from other parts of the world. They work, but the protection appears lower than for other classes of vaccines. Will that happen for Covaxin? We do not know, and hopefully not, because it has a different adjuvant, but at the moment we do not have the data.

So should Covaxin go into children now? I hope that it will be possible to conduct a trial in children with co-morbidities so that we understand vaccine performance and whether we need access to different vaccines to get better protection for this special group or not. It certainly can go into healthy children as well, but we do not actually have a measure of the amount of severe disease in healthy children and I would like to see a risk-benefit analysis that measures the burden of disease before a decision is made. 

It is important to remember that a child’s first exposure to the virus or vaccine shapes their response to the same or slightly different versions of the virus. The same happens in adults, but ultimately, our children are going to have many more exposures/infections than we are and it is, at least in my view, good to give them the best option rather than the available option. And right now, we don’t know what the best option is. 

In any case, if a decision is made to go ahead and vaccinate children with whatever vaccine is available I hope that there will be a requirement to monitor the data so that we can learn from it.