A year of race against time to find Covid-19 vaccines, hope is near

Paris: The world is close to producing a vaccine against the Covid-19 epidemic, just one year after the appearance of this new disease, in a goal that has been achieved thanks to research that has been carried out at record speed , although many questions remain.

When will the vaccine be available?

November was a crucial month when manufacturers made their first announcements about the effectiveness of the vaccines they were working on.

In Europe, the European Medicines Agency confirmed on Monday to Agence France-Presse that it will be able to license the first vaccines before the end of the year or early 2021. As of this date, many countries have drawn up their plans in recent years. days, such as Spain, Italy and France.

For its part, the United States hopes to begin a vaccination campaign in mid-December, once the FDA has obtained the license.

The Chinese authorities, in turn, have given the green light for the emergency use of some vaccines manufactured by their companies.

This advancement in the field of vaccines was made possible by an acceleration on all fronts of research, industrial production and evaluation, backed by massive funding. Typically, it takes ten years to develop and launch a new vaccine on the market.

The European Medicines Agency stresses that “the same regulatory standards related to quality, safety and efficacy are based on vaccines against Covid-19.”

However, whatever the official approval date for vaccines, not the entire population of the Earth will not be vaccinated at once.

The director general of the World Health Organization, Tedros Adhanom Ghebreyesus, recently stated that “in the first stage, the quantities of vaccine will be limited and the priority will be for the most vulnerable groups.”

Another important dilemma that will arise in this context is the equality between poor and rich countries in obtaining vaccines.

As for Gebresus, “the vaccines were developed with urgency, and their equitable distribution must also be an urgent matter,” adding on Monday that the poor and most vulnerable countries “face the danger of being ignored amid the influx of vaccines. “.

Which vaccine is the best?

It is not possible to answer this question at this time. Since November 9, four manufacturers have declared their vaccines effective: the American-German alliance Pfizer / Biontech, the American laboratory Moderna, the British alliance AstraZeneca / Oxford and the Russian State Institute of Gamalia.

Despite this publicity rush that boosted global stock exchanges, the figures were only revealed in press releases, and without publishing detailed scientific data.

The results depend on the final or third phase of a clinical trial, which has undergone tens of thousands of volunteers. Efficacy is measured by comparing the number of people who got the disease in the group that got the vaccine with those who got it in the group that got the sham vaccine.

It was revealed after a predetermined number of volunteers fell ill: 170 for Pfizer / Biontec, 95 for Moderna, 131 for AstraZeneca / Oxford, and 39 for the Gamalia Institute.

The effectiveness of the Pfizer / Bionic vaccine was 95%, of the 170 infected, only 8 were from the vaccinated group and 162 from the group that did not receive the vaccine.

The efficacy of the Moderna vaccine was 94.5% (5 patients from the group that received the vaccine, 90 from the group that received the mock vaccine).

The effectiveness rate of the Russian “Sputnik-V” vaccine is 91.4% compared to the number of 39 patients and 95% compared to the number of unidentified patients.

The calculations adopted by AstraZeneca / Oxford are more complex. The effectiveness rate of the vaccine is an average of 70%, if the results of two different protocols are combined.

The effectiveness was 90% in volunteers who received an initial half dose and then a full dose one month later. The percentage falls to 62% for the range of another group, which received two full doses, a month apart between the first and second. This indicates that the first vaccination method achieved a better immune response.

However, effectiveness is not all that counts. The AstraZeneca vaccine is the cheapest (around € 2.50 per dose). As for Moderna and Pfizer / Biontec vaccines, they have no logistical obstacles, as the technology used to manufacture them requires prolonged storage at very low temperatures (minus 20 Moderna and minus 70 degrees for Pfizer).

What are the questions that still have no answer?

Many questions remain.

The director general of the Health Organization warned that “the vaccine will complement other means in our power and will not replace them”, even if “the light at the end of the tunnel has become stronger.”

The most important question relates to the long-term effectiveness of the vaccine, because the issued accounts were prepared only two weeks after the volunteers received the last dose.

British expert Benny Ward from King’s University in London, quoted by Science Media Center, asks: “How long does protection last? Will the virus be able to transform itself to evade the vaccine, limiting the effectiveness of vaccination?”

Another basic question that arises: it is not yet clear if the vaccine interacts in the same way with the most vulnerable population group, starting with the elderly who have a weak immune system. They are more susceptible to severe forms of the disease and therefore it is important that the vaccine is useful for them.

Finally, it remains to be seen if the vaccine prevents the transmission of the infection, in addition to reducing the severity of the disease among those who received it. This is a very essential point to stop the epidemic.

Experts believe that AstraZeneca / Oxford has an advantage over other vaccines in this area.

“Contrary to what happened in other experiments, the AstraZeneca / Oxford team screened all participants each week for lesions without symptoms,” the Eleanor Reilly Academy of the University of Edinburgh said, quoted by the Science Media Center.

For its part, the University of Oxford confirmed that “we have initial indications that the vaccine is capable of preventing the transmission of infection, because a decrease in the number of asymptomatic infections has been observed.”

In an interview with France Press, AstraZeneca said that screening for asymptomatic patients does not concern all 23,000 volunteers, but only a portion of them, without announcing the expected number.

Finally, if the trials did not show serious side effects, a “continuous monitoring” process is necessary to ensure that “there are no rare, unwanted but more serious effects when the vaccine is used on a larger scale,” according to Dr. Ward.

How many vaccines are offered?

Of the four vaccines that have reached an advanced stage, 11 are in the third phase of trials, according to the latest WHO announcement on the matter, dated November 12.

Among them, many Chinese laboratory projects (such as Sinophac, Cinopharm and Cansino).

In all, 48 “candidate vaccines” are being tested in humans worldwide. In addition to the 11 vaccines in the third testing phase, there are 37 in the first phase (which aims to evaluate the safety of the product) and the second (which studies its effectiveness).

In addition to those that have already entered the testing phase, WHO is counting 164 vaccine projects in the preclinical phase.

What techniques are used?

The labs used different methods, some proven and new.

Multiple teams are working with traditional means, such as the “inactivated” vaccine technique that is developed with a virus whose infectious agents have been treated, and is the technique used by the Chinese Sinovac and Sinopharm.

There are also recombinant protein vaccines, which are based on creating an immune response through proteins and not through a virus.

As well as the technology of vaccines with “viral vectors”, which is more advanced, since it is based on another virus that is transforming and adapting to combat Covid-19. AstraZeneca / Oxford is working with this technology, as are the Russians, who are based on developing an adenovirus vaccine.

Finally, the most practical projects are based on “DNA” or “messenger RNA” vaccines. This technology is based on pumping genetic instruction molecules into cells, to drive them to make proteins or “antagonists” directed against the Corona virus. Moderna and Pfizer / Pinotech are working with this technology.

Will people trust the vaccine?

Whatever the first dates of vaccination campaigns, a fundamental question remains: will people accept to receive the vaccine in the context of a significant increase in mistrust?

According to a study published in mid-October in the British magazine “Royal Society Open Science”, a good part of the population of some countries believes in conspiracy theories related to Covid-19, which increases their distrust of the vaccine.

For example, 22% of the Mexicans surveyed in this study believed in the validity of the false idea that the epidemic “is part of a plan to impose worldwide vaccination.”

Research published in early November by the World Economic Forum and conducted in 15 countries showed that the percentage of people prepared to receive the vaccine decreased compared to August.

Only 73% support the following statement: “If there is a vaccine available against Covid-19, I will get vaccinated”, compared to 77% in August.

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