While France begins a campaign for a third dose of the vaccine against Covid-19 in shelters for the elderly (Ehpad), some countries have already generalized the booster for the entire population in order to fight against the new variants . A policy that causes divisions in the current health context, because in the world there are still great inequalities in accessing the vaccine.
A new vaccination campaign began in France on September 13 in shelters for the elderly, while the country is going through a fourth wave of the Covid-19 epidemic. Given the progression of the Delta variant, more contagious and resistant to the vaccine, the High Health Authority (HAS, for its acronym in French) recommended in its report of August 24, to carry out a vaccination booster for fragile people, at the same as for those over 60 years from mid-September.
Although up to now the Government has not given indications about a possible generalization of this third dose for the population as a whole, other countries such as Israel or Hungary have already taken the step, sparking intense debates at a time when access to vaccine is still very uneven in the world.
A third dose for whom?
Since the discovery of the initial strain of Sars-CoV-2 in December 2019 in the city of Wuhan, scientists have detected several thousand Covid-19 mutations throughout the world. Although the overwhelming majority of these variants do not present particular difficulties, some mutations offer a form of resistance against vaccines against the disease. This is the case of the Delta variant, initially called “Indian”, which is now predominant in France.
“When you get Covid-19 or if you get vaccinated, you develop antibodies against the disease. This protection lasts for a few months and then gradually diminishes. The third dose increases the dose of antibodies and then raises the level of protection again ”, explains Professor Jean-Daniel Lelièvre, head of the immunology and infectious diseases service at the Henri-Mondor hospital in Créteil.
“This boost is even more important compared to variant forms like Delta that are particularly contagious. The difficulty is in knowing to which public to administer it and when, so that it is as effective as possible ”, adds the expert.
What are the target audiences?
In late August, Israel launched a comprehensive vaccination campaign for the third dose, open to all citizens over 12 years of age. Since July, the country had allowed those over 60 to receive the booster, and since then it has administered a third dose of the vaccine to several thousand of its citizens.
For younger people without comorbidities, the urgency is not the same and there is debate about it
Although the United States is preparing to launch a similar campaign, open to all adults as of September 20, the issue arouses more reservations in the old continent. The European Medicines Agency (EMA), which is currently studying this possibility, has not yet given its opinion, but has made it known that a reinforcement for the general population was currently not an emergency.
“Today, among vaccinated people, the minimum duration of immunity is assessed to be more or less about six months,” explains Gérard Dubois, professor of public health and member of the Academy of Medicine. “We also know that, once this deadline has passed, older people lose these antibodies more quickly, so they should be vaccinated again as a priority. For younger people without comorbidities, the urgency is not the same and there is debate about it ”.
At the end of August, the European Commission specified that in the absence of a decision, the administration of the third dose would fall under “the responsibility of the States”. Although several countries such as France, Germany, Sweden or even Austria currently want to vaccinate their population at risk with a third dose, Hungary is the only country in the bloc to have opened the vaccination booster campaign for the general population.
A uniquely national issue?
Aside from the debate about the relevance of the booster campaign, the administration of the third dose raises ethical questions, as there are still great inequalities in access to the vaccine throughout the world.
Particularly on the African continent, where the level of vaccination of populations is still very low: only 3% of people have completed their vaccination schedule. A delay mainly due to the slow pace of the COVAX program, established to facilitate access to vaccines for developing countries. According to the WHO, a total of 165 million doses have been brought to the continent so far, for a population of about 1.38 billion inhabitants.
“At the country level, it is conceivable that health authorities will propose a third dose for the populations most at risk, to avoid a hospital collapse. However, comprehensively vaccinating a population with a third dose while entire countries do not have access to the first is clearly not a sensible health strategy ”, considers Jean-Daniel Lelièvre.
“Whoever thinks of a pandemic, thinks of a global strategy, and a strictly national health policy cannot defeat the virus,” emphasizes Gérard Dubois. “However, it is true that the hospital, medical and economic implications are so many that the leaders are obliged to put everything in motion to protect their populations. So much so that many of them have been criticized for their lack of anticipation in this crisis. Today, the question of the third dose is a very difficult political calculation ”.
In early August, the World Health Organization (WHO) called for postponing the use of the third doses until the end of September, to reduce the abysmal gap in access to the vaccine between rich and poor countries.
A month later, its CEO, Tedros Adhanom Ghebreyesus, was blunt: “I will not remain silent while the companies and countries that control the world’s supply of vaccines think that the poor countries of the world should settle for the remains.”
For his part, US President Joe Biden prefers to emphasize the 114 million doses sent to developing countries, making the United States the world’s leading donor of Covid-19 vaccines.
This article was adapted from its original in French