The Trap of the Data Gap: How Do We Know India’s COVID Vaccines Are Working?

India has the most AstraZeneca COVID vaccine recipients globally, yet, real-world data of its efficacy is lacking.

COVID-19 Policies in India: Why is the data behind them so inaccessible? 

(Photo: iStock/altered by the Quint)

Yet another year comes to a close, and yet another highly transmissible COVID-19 variant, Omicron, has picked up the baton (from its predecessor, Delta) to remind us that the pandemic is not over yet.

The difference, though, is that this time around – unlike when the second wave hit – we're better prepared, or at least have the potential to be.

We have a wider vaccine coverage, many countries have started administering boosters, some parts of the population have developed natural and hybrid immunities, and we have a lot more data to make more scientifically sound policies to contain the pandemic than we did when we were blindsided by Delta.

But where exactly is this data?

How long does Covishield vaccine's efficacy last?

Would Covishield and Covaxin make for good booster shots?

When should India start rolling out booster doses?

Do all adults in India even need booster doses?

Why is it that the answer to most of these questions hits a wall plastered with the words, 'not enough data'?

What Real World Data is Saying

Before we look at the state of affairs in India, let's look at what data from other parts of the world has found.

Several studies from Israel, South Africa, and other countries have found that COVID vaccine immunity starts waning after a certain period of time.

"You cannot find out the duration of the immune response in a clinical trial you can only find out afterwards, in the real world. That is where you need the real-world databases to be well integrated."

Dr Srinath Reddy, epidemiologist and President of Public Health Foundation of India

Earlier this week, one such study was published in the Lancet. It analysed data from 42 million and 2 million fully vaccinated people from Brazil and Scotland respectively, to find that the efficacy of the AstraZeneca COVID-19 vaccines starts waning three months after the second dose, not only against infections but also severe illness.

Something similar was found in a study conducted in South Africa on the Pfizer vaccine.

This is an important finding given that experts have been emphasising the distinction between infections and illness, and how, as long as the vaccines are protecting against severe illness, they're working well.

Real world studies like this also strengthen the case for rolling out booster doses, especially for high-risk people like healthcare workers, the elderly, and immunocompromised people.

What does this mean for the vaccinated Indian population?

"For immunocompromised people, the elderly people and for the people who are likely to have high repetitive viral load exposure in the case of a new outbreak like healthcare workers who were vaccinated in the initial part of 2021, and their immunity would have waned, I think are important candidates for boosters with no doubt about that," says Dr Reddy.

This is something experts have been emphasising, and is supported from studies across the world.

Prime Minister Narendra Modi has now announced that frontline workers and those over 60 will be eligible for a third 'precautionary shot' of the COVID vaccine starting 10 January.

And yet, there isn't any large scale data in the public domain in India regarding booster shots.

Can the data from the Scotland-Brazil study be extrapolated to India –considering a majority of Indians have been vaccinated with Covishield (AstraZeneca) COVID vaccine?

Epidemiologist Dr Chandrakant Lahariya is of the opinion that it can't, as studies like this come with many caveats.

He talks about how, although this study confirms what experts have known about the effectiveness and neutralising antibodies from vaccines declining over a period of time, it is not without its limitations.

"Every setting is different. If a single or a few studies were applicable to all other settings, then we would not have required more studies from different settings."

Dr Chandrakant Lahariya, Epidemiologist

In that case, the question that naturally arises is, where is India's real-world data on vaccine efficacy?

‘Not Enough Data’: The Widening Gap Between Science & Policy

"That is the point which many researchers and experts are raising in India, that the Indian government needs to use data effectively," says Dr Lahariya.

"So essentially, Indian government has a lot of data available with them. It has data on the vaccination of individuals, then it has data on the people who were hospitalised in different settings."

Dr Chandrakant Lahariya, Epidemiologist

He also talks about how in a country like India, doing retrospective real-world studies like the Scotland-Brazil study in the Lancet shouldn't be very difficult to pull off. "There is enough expertise in India and this kind of analysis can be done," he says.

"Phase four trials are a standard practice, it’s not an unreasonable expectation," adds Dr Swapneil Parikh, Internal medical specialist and the author of the book, The Coronavirus: What You Need to Know about the Global Pandemic.

"Even if it does not share, if the government has data, they should analyse the data and we can get many of the answers, if not all of the answers, which will help in providing useful insight."

Dr Chandrakant Lahariya, Epidemiologist

Speaking of a systemic obstacle, Dr Swapneil Parikh says, "In india, data regarding vaccination are more fragmented. Until recently, we didn’t have a centrally coordinated effort or national health stack."

"In the case of say, NHS in the UK, such studies can be conducted quickly because data infrastructure is inbuilt into the system. Indian hospitals have conducted some studies regarding vaccines, but these haven’t been done at a scale that one would expect for a country as large and diverse as India."

Dr Swapneil Parikh, Internal medicine specialist, Mumbai

According to Dr Reddy, "all our databases should be well-integrated to do these kinds of estimates."

"The vaccine database, RT-PCR database, the rapid antigen test database, the hospitalisation database, if they have been operating separately, you won’t have a combined database to characterise individuals with the breakthrough infections and reinfections," he explains.

Although some real-world studies have come out of India, like the one that found Covaxin to be 50 percent effective during the peak of the second wave, no large scale studies from the government bodies have been released to the public domain since.

"As an individual, I do not know whether that kind of analysis has been done," says Dr Lahariya, "but definitely that kind of analysis is not available in the public domain."

"It is possible that government is looking at that data and using it. But I cannot comment whether the government, experts and government committees have analysed that data or not, as it's not available in public."

Dr Chandrakant Lahariya, Epidemiologist

The Quint reached out to scientists at the Indian Council of Medical Research (ICMR) – the central body collecting and generating COVID-19 data – including the director of ICMR-NIE, but we didn't get any response.

With Great Data Comes Great Responsibility

"India has the largest pool of AstraZeneca (Covishield) vaccine recipients in the world. It is our duty, not just to our own citizens but also to other countries, to conduct scientific studies on effectiveness and safety of this vaccine."

Dr Swapneil Parikh, Internal medicine specialist, Mumbai

The lack of access to data has been an issue that has been raised by scientists across the world time and again since the beginning of the pandemic.

Earlier this year, a slew of prominent scientists from across India signed a petition asking the central government to make data collected by the ICMR over the course of the pandemic more accessible.

"A lot of interpretation analysis can be done from Indian data, and that's not being done. And that's what many experts outside government are demanding," adds Dr Lahariya.

"In the scientific world, it is always useful that not only is data analysed by some individual, but is peer-reviewed and published for public scrutiny."

Dr Chandrakant Lahariya, Epidemiologist

What we do and don't need to know

While some important data is locked up at the end of impossible mazes, the general public is bombarded every day with data that they have little use for, but seemingly serves the purpose of virtual pats on the backs of health authorities.

Sure, its great to get daily updates of how many vaccines have been administered in the country, but this data is of little consequence if we don't know how well these vaccines are really working, and how long the protection will last.

While there have been some small studies that have attempted to answer this question, as far as real world studies on a large population is concerned, 'there's not enough data'.

Lack of data in the public domain means citizens and scientists in the country wouldn't know if critical COVID-19 containment policies like approving booster doses are made by the government based on science, mere discretion, or pragmatic convenience. As a result, we may remain stuck in a vortex of 'not enough data'.

Giving his final thoughts on the matter, Dr Lahariya says, freeing up data "is how science will benefit and progress."

"It will provide a more robust and better understanding of decision making. The data should be speaking to the public rather than people not knowing why a particular decision had been made or why not."

Dr Chandrakant Lahariya, Epidemiologist