To boost or not to boost

We must not go for third doses when so much of the world has not even got its first Covid-19 vaccine shot

Photo: UNICEF NEPAL

In terms of global vaccine equity, the answer to the question of whether it is ethical for rich countries to boost with a third dose of  Covid-19 vaccine, seems like a no brainer.

But ethics aside, it has been pointed out that no one is safe until everyone is safe. It is in the public health interest of rich countries to ensure that as many people around the world are vaccinated to prevent new variants and spikes.

The graph below starkly illustrates the big gap between the jab and jab-nots – showing the wide chasm between rich and poor countries in terms of the proportion of the population which has got even the first dose.

Booster vaccination is a moot point for low-income countries because at the moment the option is limited to high- income countries, where some research has shown waning antibody presence and the authorities in the US are advising a third dose eight months after the second one.

As of now there is only scant data to show that boosting will help real-life protection in the general population. Clearly the vast majority of the people who received the full dose of approved  vaccines, including the Chinese VeroCell here in Nepal, already have adequate protection against severe (as opposed to mild or moderate infections) Covid-19 disease with the present vaccine schedule.

Crucially, a strong international drive to vaccinate the unvaccinated could potentially save many more lives than would boost the already vaccinated.

But this is a very wily virus which almost overnight changed the rules of the game by mutating into the highly infectious Delta variant. We need look no further than what happened in neighbouring India earlier this year as this variant ripped through the unvaccinated population regardless of herd immunity that was thought to be widespread.

Delta surged across the open border into Nepal, where it overwhelmed the country’s inadequate and inequitable health care system. There is credible data to suggest that there might have been 3-5 million excess deaths in India during the second wave.

Estimates for Nepal by the Institute of Health Metrics and Evaluation of the University of Washington in Seattle show that although the official cumulative deaths due to Covid-19 as of this week was nearing 11,000, the real figure with excess mortality is closer to 40,000.

It is among the vast number of the unvaccinated that the virus has a greater chance of randomly mutating and becoming a variant (from alpha to omega and now the mu variant in South America) and potentially spreading worldwide.

Every time the virus replicates, its likelihood of mutation increases. The novel coronavirus, unlike the other SARS-CoV-1 from 2003 may not be as keen on killing people as it is in perpetuating infections by replicating as much as possible .

After India, the Delta virus affected the UK population in a widespread manner, but there was one huge difference -- in Britain it infected many who had already been vaccinated, even though the severity of the illness was significantly lower in this subset.

Hence, as these variants generally develop in the unvaccinated population and some (there are 15 variants at present) turn out like the Delta variant, it would be in the enlightened self-interest of the richer countries to have as much of the world vaccinated as possible so that random mutations and variants will be substantially limited, and will not reach their shores.

But such enlightened self-interest seems to be lacking in high-income countries, especially because there are not enough vaccines to go around, and rich nations perceive an immediate benefit from boosting.

Israel is already giving third jabs and France, UK and the US are strongly considering boosters. Boosting may be a good idea if the Covid-19 vaccine supply was plentiful. But currently the supply is limited and more than half the world’s population has not received even a single dose of the vaccine.

Sadly, many in low and middle income countries are waiting for doses through the COVAX facility and drug manufacturers like Serum Institute of India scramble to fulfill previous contracts while grappling with the Delta virus at home.

What is even more unconscionable is that many rich countries are throwing away expiring vaccines. And now with new orders for booster vaccination programs from high income countries, the developing world will have to wait even longer to have their contracts filled.

With booster doses planned for the rich world, it may indeed be a zero sum game for the world if the supply of the approved Covid-19 vaccines is not dramatically increased. The good news is that Serum Institute of India, where Nepal sourced its first lot of Astra Zeneca Covishield vaccine until the pandemic took a turn for the worse in India, has greatly increased its production capacity.

Given the experience of the past nearly two years, most high income countries are likely to ignore ethical considerations regarding vaccine equity and booster doses.

Many institutions in the West that deal with global health may be embarrassed about not being able to persuade their governments to put their money where their mouth is and do the right thing.

So far, their pleas for vaccine equity have generally been ignored – even though they know an effective global vaccination drive would ultimately benefit them by reducing the risk of new variants emerging.

In practice, if the production of vaccines revs up and COVAX is able to ship more vaccines to poor countries, regardless of boosting or no boosting by the richer countries, millions of people in the Global South will benefit.

In the meantime, we have to continue to mask up, avoid crowds and sanitise, because the vaccine per se will not stop transmission.

The other bit of good news is that the Nepal Health Research Council in conjunction with other local collaborators is  sequencing (identifying the molecular structure) of Covid-19 virus samples from various parts of Nepal.

The Sanger Center, the world’s premier genomic institute based outside Cambridge in the UK, will validate the results from Nepal and enhance our capacity building in molecular medicine.

This should help us in promptly identifying variants of Covid-19 so Nepal can deal with future infectious disease outbreaks in a scientific and orderly manner. Covid-19 has emphasised the additional significance of sequencing even for other rampant diseases like  tuberculosis and typhoid in South Asia.

Buddha Basnyat is a physician and clinical researcher at Patan Academy of Health Sciences and a frequent health columnist for Nepali Times.

Buddha Basnyat

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