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COVID-19 vaccine: 6 things to know

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The SARS-CoV-2 vaccine is generating plenty of questions and fake news. Six things to know about this anti-COVID treatment.

Is this type of virus a good candidate for a vaccine? Yes

SARS-CoV-2 is a relatively stable virus. This means that it doesn’t evolve very rapidly, even though it mutates like other viruses. The analyses have shown very little variation, considering the large number of people infected over the months. Such stability allows our body time to learn to produce antibodies.

This isn’t the case for all viruses. For example, with HIV, in the time the body learns to produce antibodies, the viral envelope has changed so much that the antibodies can no longer neutralize it.

Even though there are still a lot of points to clarify on the immune response to this coronavirus, observations give reason to believe the antibodies developed during the infection are effective.

However, despite the tremendous efforts deployed by researchers all over the world, it may take awhile to find a vaccine. They must find precisely the right protein and the right formulation that will produce the right antibodies for our immune system.

 

By trying to go too fast, is it possible the researchers won’t follow the rules? Maybe

Because of the emergency, any promising COVID-19 vaccine is likely to speed up the usual steps. These are: tests in vitro or on animals, limited clinical trials followed by large-scale trials, approval processes by the health authorities. It could be tempting to shorten the clinical trial period, This could risk missing eventual medium or long-term side effects, which normally occur with new vaccines. This could create an opening for anti-vaccination activists. They would claim the vaccine isn’t tested according to the rules or is likely to present risks.

At the end of July, the World Health Organization (OMS) listed 26 vaccines in the clinical trial phase and 139 in the preclinical phase. The London School of Hygiene & Tropical Medicine counted more than 200 vaccine projects, about thirty of them in clinical trials. Clinical trials are human trials that seek to prove a vaccine is effective and safe. They are conducted in three phases. For the candidates that are currently the most promising, these trials should continue up to the end of the year.

Finally, before billions of doses can be manufactured and distributed to the different populations, the vaccine must also be approved by the health authorities of different countries.

 

Encouraging results: are we close to the finish line? No

Encouraging results were disclosed at the end of July. Does this mean we’re close to the finish line? Not so fast. These results come from Phase I and II trials, which analyze how people react to injections. This means the evaluation mainly concerned the safety and dosage of the vaccines. No serious adverse effects were recorded. The side effects observed the most were fever, fatigue and pain at the vaccine injection point.

The effectiveness of these vaccines will have to be established in a Phase III trial, with a larger number of participants. This involves injecting the vaccine into populations “at risk”. So it may take months to see whether fewer people in these groups develop the disease than “non-immunized” people.

 

Could there be more than one vaccine? Yes

Researchers warn that the first vaccines to arrive on the market aren’t necessarily the most effective or the safest.

There are many recipes under study, so several vaccines could be marketed. Just look at influenza. The type of vaccine effective for children isn’t the same as the one that works well for seniors.

A vaccine that doesn’t prevent people from being infected could still be considered a success, if it contained the progression of COVID-19 in an infected person. It could also be successful if it prevents cases of severe respiratory distress, which are responsible for most intensive care hospitalizations.

 

A mandatory vaccine? Unlikely

Is it conceivable that the eventual vaccine will be mandatory? In Québec, like almost all Canadian provinces and most States in the USA, the law allows anyone to refuse treatment, and no vaccine is mandatory.

However, the Québec Public Health Act allows the State to impose a vaccine on all or a portion of the population. It can also oblige a person to receive care due to the high degree of contagion of a disease. This is the case for “mandatory treatment” diseases, such as tuberculosis.

The answer to the question will therefore depend on how the public health authorities assess the seriousness of the situation. The evolution of the scientific data on COVID-19 and the state of public opinion, favourable or unfavourable to a vaccine, could tilt the balance.

 

A vaccine for all, or served for rich countries?

Some countries, such as the United States and China, say they are ready to immunize their population in priority, if they can. Other countries insist that the vaccine be accessible for all. At the World Health Organization (WHO) meeting in May, over 130 countries adopted a resolution to ensure fair access to all essential health products and technologies to fight the virus, and their fair distribution.

These countries want to avoid what happened in the 2009 H1N1 flu pandemic. At the time, the rich countries negotiated major advance orders of vaccines, squeezing out the poor countries. This has already begun. Over the past few weeks, the United States signed agreements with laboratories to obtain priority on the future production of a vaccine. This involved investments of over $8 billion at the end of July. Canada is in discussion to pre-order vaccine doses for its population.

It remains to be seen how the WHO resolution will be translated in the field. That’s because there is no world entity mandated to order and pay for manufacturing of vaccines worldwide.

The Global Alliance for Vaccine and Immunisation (GAVI) is an international non-profit organization based in Switzerland. GAVI’s aim is to increase access to vaccinations worldwide. It intends to ensure that the planet’s poorest inhabitants aren’t left aside when a vaccine becomes available.

GAVI participates in fundraising campaigns with governments and the private sector to speed up children’s access to vaccination. It also encourages the emergence of new vaccine manufacturers, particularly in the emerging countries, to strengthen competition and lower the cost of vaccines.

 

 

 


This article was originally published on the website of L'Agence Science-Presse (French only).


 

 

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