Does it make sense to infect healthy young people to speed up the Covid-19 vaccine?

The proposal gains consensus, and is supported by Nobel laureates and renowned scientists. But the ethical and practical limits are not lacking, and it could even be useless

(photo: Leonardo Fernandez Viloria / Getty Images) Edward Jenner's times were simpler. You could infect your gardener's child with smallpox, wait for the disease to run its course, and then return to infect it (or rather inoculate it) with human smallpox. And suddenly find yourself inventing one of the most effective medical procedures in history. Today many would turn up their noses at such an unprejudiced experiment. Or at least, they would have done so until last year, because with the planet in spasmodic expectation of a vaccine against Covid 19, there are those who press for a return to the origins: why not infect a certain number of volunteers, and see if the candidates Are vaccines under development as effective and safe as we hope? A controversial proposal that revolves around the 1DaySooner advocacy group, and which in recent weeks has continued to gain illustrious sponsors: an open letter addressed to the director of the American Nih now boasts over 2,000 illustrious signatures, including those of 15 Nobel laureates. Not everyone in the scientific community, however, agrees either on the usefulness or on the secularity of the solution.

In actual fact, the proposal is not exactly news. The administration of pathogens to healthy volunteers for research purposes or to test new drugs and vaccines is something that in English is called a human challenge trial (or Htc ), and it is always, even if with very strict rules, and in a situation quite different from the current one. It is made with cholera, typhoid, malaria, and even influenza. All diseases are potentially fatal, but for which there are medicines and life-saving therapies are effective and well-tolerated. The difference, in the case of the coronavirus, is that here it would be a leap in the dark: if something should go wrong, at the moment there are safety nets, medicines or therapies.

There is, however, who was not afraid, and is willing to risk his own health to help us to emerge from this pandemic. It all started with two young americans, a biologist by the name of 22-year-old Sophie Rose, and the lawyer, 38-year-old Josh Morrison , co-founders of 1daysooner , who for months recruit volunteers to put the regulators in the front of the accomplished fact: the guinea pigs consenting we are, and with their help, the race for the vaccine could prove to be a short one. Numbers to the hand, 1daysooner and the experts who support the initiative believe that the potential benefits outweigh by far the risks, all in all the remote if you choose carefully the audience for volunteers to be involved in the research. Covid, as we know, is a disease that reveals itself serious usually in the weakest and the elders of the society. By limiting participation to youth in health, with less than 30 years, the risk of death related to the disease should not exceed 0.03% (3 chances over 10 thousand) and those that develop symptoms severe enough to merit a hospital would grind to a halt at about 1% . Quite a bit of content to transform the hazard into an acceptable solution.

As it would be brought forward in a trial like this? To describe it is a Who report of June: the volunteers would be divided into two groups, one intended to receive the vaccine and one of which would be inoculated with a placebo. Participants should be young people (the report suggests the use of people between 19 and 25 years of age), in health, and should be kept in isolation within departments high security for the duration of the trial. After receiving the vaccine, and having waited a few days to make sure that it has time to take effect, all participants would be exposed to the virus, and monitored to verify the situation. In this way you could quickly check the safety and efficacy of the vaccine, and collect valuable data on the clinical evolution of the covid in a setting that was controlled. Not having to wait for participants to come in contact with the virus on their own (as happens in a normal trial for the vaccines) the duration of the study could be much shorter. And not having to rely on the case to expose the participants to the disease, you may have reliable results by using a very small number of people.

All things considered the time savings may be concrete, albeit rather limited. Not being able to completely eliminate the other steps of the process of approval of the vaccine, we are talking weeks , at most a few months , which can be earned on the roadmap. But in view of the counts of the dead is constantly on the rise, for the supporters of the project may be worth. From here the name of the initiative, which in Italian could be translated as “ only a day before. ”

Despite the many favorable opinions in the scientific community (and not only) there are also strong doubts. On the other hand we felt to repeat it for months, not even the young people are safe from this coronavirus, and the possibility of using real human guinea pigs for accelerating the development of a vaccine seems to clash with the principle of maximum precaution followed so far. Even if the vaccine proves to be effective and risk-free, half of the participants to a possible trial would address the disease, only protected by a placebo, with the consequent risk (minimal but present) deaths and (more concrete) of complications and health problems in the long term. The risks also exist even for the participants that would be inoculated with the vaccine, because the possibility that this proves to be effective in 100% of cases is a possibility rather remote. And all without a great certainty that a human challenge trial proves to be able to really shorten the time for commercialization of the vaccine.

One of the steps the most important, and time consuming, of the trials for the new vaccines, concerns the collection of data on safety. And in order to have reliable results, serving many participants, as the potential serious side effects emerge in a small percentage of the participants. In this sense, having a group of volunteers, to whom inoculate the vaccine and the virus would not help you particularly, because you would need, however, more extensive studies to make sure that there are no dangers, even in a very small percentage of cases. The vaccine also would like to target main elderly and sick, the categories most at risk to Covid. And experiment with it on young people in health would not provide very reliable data in this sense. The risk, says an article on Stat expert vaccines Michael Rosenblatt , is that the young and well-meaning volunteers of any human challenge trial are to risk their life for nothing.

finally, There is another problem, which concerns the front of the communication. What would happen if one of the young volunteers of a human challenge trial to end to fall seriously ill, or even worse, die? Immaginatevelo: with the novax that continue to rage everywhere, and the overabundance of fake news are circulating already around this pandemic, the effects of such an accident could prove devastating. And then we could find us even with an effective vaccine, and large slices of the population that refuse to use it.