The COVID-19 Vaccine: When will it arrive? It will work? When will the pandemic end?


Is there already a vaccine against COVID-19?

There have been several potential coronavirus vaccines that have reported promising results in trials, but none have been licensed for use in the United States or Europe yet.

Russia announced in August that its Sputnik V vaccine had been approved, but the announcement was criticized as “dangerously premature” because it had not yet been tested in large numbers of people.

Read | Russia invites Europeans to produce its Sputnik vaccine

In November, Pfizer and Moderna announced that their vaccines had been shown to be 90% and 94.5% effective, respectively. Experts called the news promising, although several questions remain, in particular about whether vaccines protect against transmission of the infection and how long their protection lasts.

Michael Mina, a professor at the Harvard School of Public Health, explains that there may be an early immune response to the vaccine that does not persist, for example. It states that the body may be producing antibodies that then die.

“We may be measuring the effects of an impressive army [de anticuerpos] of the first line that responds to the vaccine – but we must be careful not to assume that the same effectiveness persists after most of the troops disappear, “explained mine on his Twitter account.

But, he added, the vaccine results showed that the vaccines were targeting the correct protein, and many reveal that the high efficacy provided hope that the vaccines would work against the virus.

“How many more [anticuerpos] they start to be used, the longer they last “said Dr. Barry Bloom, former dean of Harvard’s TH Chan School of Public Health, at a press conference Nov. 16. Dr Bloom said the efficacy of over 90% was “probably better than any expert’s expectations.”

Although experts say that as trials continue, that efficacy is likely to decline and more cases of COVID-19 are confirmed among the participants.

“We must assume that these clinical trials have been developed under ‘optimal’ conditions, and efficacy data may differ – and eventually be less – when vaccines are applied in field conditions, “Professor José Vázquez-Boland, President of Infectious Diseases at the University of Edinburgh School of Medicine, told Euronews.

When will the first COVID-19 vaccines arrive in Europe?

“If all goes well and, of course, this is pending authorization from the European Medicines Agencywe hope to be able to have vaccines available, possibly by the end of 2020, starting in 2021, “said EU Health Commissioner Stella Kyriakides last week.

Andrea Ammon, who heads the European Center for Disease Control, proposed a similar timetable. He told AFP that in an optimistic scenario there could be vaccines for the first quarter of 2021.

Health workers and vulnerable groups will be vaccinated first, but details of how that supply chain will work are still being worked out, Ammon told AFP.

“In the best case, [la distribución de la vacuna] it could be even before the end of 2020 for some pilot sector of the population, for example, some people at risk or health workers, with the probability that mass vaccination will spread progressively throughout 2021 “, he explains Vazquez-Boland.

World Health Organization chief scientist Dr. Soumya Swaminathan said on November 16: “We believe that at least the first half of next year will be a period of very, very limited doses. Supplies will be limited. There are agreements. Bilaterals that companies have done. Many of the doses have already been reserved by some countries. “

Meanwhile, the European Medicines Agency is working to rapidly authorize vaccines and has already started a “continuous review” of some vaccines, to speed up the authorization process.

How long will it be before the COVID vaccine stops the pandemic?

Achieving herd immunity – when a large enough portion of the population is immune to prevent the spread of infection – would depend in part on the efficacy of the vaccine and its distribution.

“Its origins come from veterinary medicine,” explains Dr. Vázquez-Boland to Euronews. The “threshold required to effectively stop the spread varies from one infectious disease to another,” he adds.

It depends in part on how infectious the disease is and how effective immune protection is. “We have many vaccines that save lives, measles is one such example, a highly effective vaccine with an efficacy of over 95% and yet we still have measles outbreaks,” says Dr. Kate O’Brien, director of immunization at the World Health Organization, at a press conference on Monday.

“Getting to the efficacy of the vaccine is like building a base camp on Everest, but the climb to the top would really be a cradle,” adds Dr. O’Brien.

Dr. Bloom, who is also a research professor at Harvard, explains: “There will still be a lot of people who don’t get vaccinated in the first six months or a year and who have the ability to transmit the infection.”

This means that people, even those who are vaccinated, will have to continue wearing masks and practicing some forms of distancing to prevent high levels of virus in the community, he added.

“There is no doubt that the greater the efficacy of the vaccine, the fewer people will have to receive it to reach [la inmunidad de la manada]”added Dr. Bloom at a Harvard School of Public Health press conference.

What are the main challenges for vaccine distribution?

There are many vaccine supply chains to immunize children and adolescents. But COVID-19 vaccines will need to target adults, who are at higher risk of serious illness, experts say.

The best bet would be to have multiple vaccine candidates because some vaccines will be better for certain circumstances than others.

Professor Robin Shattock from the Department of Infectious Diseases at Imperial College London told Euronews that “reach out to everyone and make sure they get two doses [y] catching those who for whatever reason skip doses will be a great undertaking. “

That means that for some low- and middle-income countries, a one-dose injection that provides immunity and does not require any boosters would be better so they don’t have to find people again for second doses. But the vaccine will also need to be distributed to many different populations in higher-income countries.

Less access to primary care could lead to “less access to the vaccine in the poorest areas due to the lack of human resources to carry out the program in these areas,” according to a Royal Society report on the distribution of the vaccine in the UK, for example.

“The cornerstone is always the primary care networks. These should be adequately strengthened and prepared to apply both the vaccination strategy and the supervision (phase 4) of safety and efficacy”, explains Professor Vázquez-Boland, who points out that It will be important to monitor any adverse effects of these new vaccines. Distribution is also affected by the way vaccines are stored.

That means that for some low- and middle-income countries, an injection of a dose that provides immunity and does not require any booster would be better so that they do not have to find people again to receive the second doses.

But the vaccine will also need to be distributed to many different populations in higher-income countries. Less access to primary care could lead to “less access to the vaccine in the poorest areas due to the lack of human resources to carry out the program in these areas”According to a Royal Society report on the distribution of the vaccine in the UK, for example.

That means that for some low- and middle-income countries, a one-dose injection that provides immunity and does not require any boosters would be better so they don’t have to find people again for second doses.

But the vaccine will also need to be distributed to many different populations in higher-income countries. Less access to primary care could lead to “less access to the vaccine in the poorest areas due to the lack of human resources to carry out the program in these areas,” according to a Royal Society report on the distribution of the vaccine in the UK, for example.

“The cornerstone is always the primary care networks. These should be adequately strengthened and prepared to apply both the vaccination strategy and the supervision (phase 4) of safety and efficacy,” said Professor Vázquez-Boland, who points out that It will be important to monitor any adverse effects of these new vaccines.

Distribution is also affected by the way vaccines are stored.

One advantage of Moderna vaccine, for example, according to experts, is that it does not need to be stored at ultra-cold temperatures, and it can be stored in a normal refrigerator for 30 days, making it easy to distribute.

“It will also be a huge challenge to manufacture and distribute vaccines globally with the ever-present risk of a black market for fake / counterfeit vaccines.”adds Professor Shattock.

How problematic is skepticism about vaccines?

Experts have said that changing people’s minds about vaccines could be the key to ensuring herd immunity is achieved.

“I am concerned about the anti-vaccine movements,” said Dr. Bloom, stating that it is a “powerful movement” and that the tools we have to deal with misinformation are more “limited” than the tools we have to make a vaccine work.

Heidi Larson, from the London School of Hygiene and Tropical Medicine, told a panel moderated by Euronews in September that there were important lessons to be learned from the Ebola epidemic.

He explained that experts should have “empathy” with individuals who may be unsure about a vaccine and work on building trust. “We can go in there and start communicating and getting involved”, concluded.


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