WHO is right to call a temporary halt to COVID vaccine recalls

The World Health Organization (WHO) has called for a moratorium on COVID-19 recalls until the end of next month, aiming to ensure at least 10% of people in all countries are vaccinated before additional doses are dispensed. It is a compelling argument. Like Nature in press, 58% of people in high-income countries had received at least one dose of the vaccine; in low-income countries, the number was only 1.3%.

In addition, the case of boosters has not yet been proven. Most of the COVID-19 vaccines currently in use remain extremely effective for months after administration, especially against serious illness and death. In times of vaccine shortage, the choice to distribute boosters should be guided by evidence of benefit and consideration of the cost of delayed vaccine delivery to vulnerable people and health workers in other countries. So far, there is little evidence that boosters are needed to protect fully vaccinated people.

Unfortunately, many countries are moving ahead with boosters anyway. Israel has started administering third doses of Pfizer’s mRNA vaccine to people over 50 and other vulnerable groups. France, Germany, UK, and US all plan to provide boosters to certain groups. In the United States, more than a million people have successfully obtained an unauthorized third dose.

In some cases, boosters may be warranted – if the evidence suggests that usual doses are not working, for example. A study of people who have had an organ transplant, which means they have to take drugs that suppress the immune system, found that almost half had no antibody response after two doses of the vaccine. MRNA (BJ Boyarsky et al. JAMA 325, 2204-2206; 2021).

Recalls may also be needed if vaccines made from inactivated viral particles, namely those from Chinese manufacturers Sinopharm and Sinovac, prove to offer inadequate protection against serious illness or death from variants such as Delta. A COVID-19 outbreak in Indonesia that has affected many health workers fully vaccinated with Sinovac, and outbreaks in other countries dependent on Sinovac vaccine, have led authorities to consider boosters using other vaccines – even though vaccines are far from the only factor involved in increasing disease rates.

All other vaccines currently in use appear to be over 90% effective against hospitalizations and deaths from COVID-19. Although some studies have shown that the antibody levels induced by the vaccine decrease after several months, this is typical for all vaccines and does not necessarily indicate a decrease in protection against the coronavirus.

Scientists do not yet know what additional protection a booster might give against the disease, or how long a boost will last. However, on average, an unvaccinated person exposed to the coronavirus is much more likely to both be infected and spread this infection than a person who is vaccinated. In addition, they are over 90% more likely to be hospitalized or die from the disease. Choosing an unknown but potentially incremental benefit for one person in a wealthy country rather than a huge and life-saving benefit for someone elsewhere in the world is a losing strategy, as new variants will inevitably emerge in places where the spread of COVID-19 continues unabated.

Instead of offering reminders to large numbers of people, richer countries need to be more active in getting the world vaccinated – and there are several ways to do it.

First, rich countries must keep their promises to support COVAX, the international alliance that provides vaccines to low-income countries. It remains below its modest goal of vaccinating the most vulnerable 20% of the population by the end of 2021.

However, global vaccine availability is limited – and will only become so if boosters become commonplace – so vaccine donations alone will not be enough. Executives in countries whose companies have benefited from public funds – like BioNTech in Germany and Moderna in the United States – should use their influence to expand manufacturing. Many other wealthy countries must support a proposal led by India and South Africa – which has US backing – for a temporary exemption from vaccine patents.

These agreements must be accompanied by funds to enable new manufacturers to start up quickly and safely, as well as funding for countries to enable them to purchase doses of the vaccine and distribute them to their populations. Typically, this process takes place over years, if not decades, but time is of the essence in a pandemic – and the needs are vast. Patent waivers alone will not solve the problem; neither vaccine donations nor a temporary moratorium on recalls. The world must act on all fronts simultaneously.

Allowing COVID-19 to spread to low- and lower-middle-income countries – where, overall, less than 15% of people are vaccinated – could result in the death of millions or face severe long-term complications of severe COVID-19. Economies will erode as businesses and schools remain closed. And soaring COVID-19 levels will promote the development of new variants that could be even more transmissible than Delta, more deadly than existing strains, or able to evade the immune response. The International Monetary Fund last month warned that highly infectious variants could derail the world’s economic recovery and wipe out $ 4.5 trillion in global gross domestic product by 2025.

If vaccines were not rare, boosters would be less controversial. But focusing on reminders when more than half the world runs out of vaccine doses is shortsighted and will only prolong the pandemic. For rich countries, this strategy means that they will run their tails indefinitely in terms of new variants. And for the rest of the world, it means prolonging unnecessary suffering.