First COVID Vaccines Are a Scientific Victory, but These Challenges Remain

The remaining question is how effective is the new vaccine in preventing infection, not illness

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Frances Gogh receives the first of two Pfizer/BioNTech COVID-19 vaccine jabs, at Guy's Hospital in London, Britain December 8, 2020.
Frances Gogh receives the first of two Pfizer/BioNTech COVID-19 vaccine jabs, at Guy's Hospital in London, Britain December 8, 2020. Credit: VICTORIA JONES - AFP

UPDATE: First Pfizer vaccines arrive in Israel

Margaret Keenan, a 90-­year­­-old British woman, was the first person to receive the coronavirus vaccine made by Pfizer and BioNTech on Tuesday, as the United Kingdom ­– the first country to approve the vaccine – began inoculating its population. In the coming weeks, 800,000 British citizens will be vaccinated.

The innovative vaccine produced by Pfizer (with its partner BioNTech) and a similar one manufactured by Moderna, which is expected to be approved shortly, are a scientific triumph. They are the product of an unprecedented mobilization of the global scientific community against the coronavirus.

The achievement is especially noteworthy for the record speed in which the vaccines were developed and approved to fight the virus, which has to date claimed the lives of one and a half million people around the world.

Margaret Keenan, 90, being applauded by staff after becoming the first British person to receive the new COVID-19 vaccine, in Coventry on Tuesday. Credit: Jacob King/AP

“When you begin something in any particular laboratory, you never know if it will lead to anything or not” said Hebrew University President Prof. Asher Cohen in conversation with Haaretz last April. “But when we’re talking about thousands of labs that are doing it in tandem, there is no doubt that in the near future, sooner than most people think, solutions will be found.”

Even back then, Cohen estimated that a vaccine would be available by April 2021. He now says that this was one of the only predictions he made about the pandemic that turned out to be accurate.

“Why did I make that prediction? Because I knew precisely where the science was,” he now explains. “Due to the scientific knowledge that had accumulated up to that time, I knew that with the immense work invested around the world on this topic, we’d really find a vaccine.”

Josephine Faleye receives the Pfizer/BioNTech COVID-19 vaccine on the first day of the largest immunisation programme in the British history, in London, Britain December 8, 2020.Credit: JACK HILL - AFP

Cohen emphasizes that he couldn’t have known that it would be the RNA-based vaccine that would be the first to succeed. But he had no doubt that someone would make it to the finish line. “Over many decades, the world had established research universities across the globe, and suddenly the time came in which this led to a practical result. It’s not just one university that did it, it’s the combination of all research universities,” he says.

In the medical history of the human race, even in the modern era, treatment of and inoculation against an epidemic has usually become possible only after the epidemic was already over. This is not surprising, given the fact that the development and approval of a vaccine usually takes years. This time, however, Moderna’s vaccine was ready by January 13, only two days after the first genetic sequence of the virus was published. The Pfizer- BioNTech vaccine was ready shortly after.

The technology on which the two new vaccines is based has been studied over the last decade as a method for treating various diseases, such as cancer. In both vaccines, molecules called messenger-RNA are injected into the body, encased in small fat bubbles called liposomes.

Josephine Faleye receives the Pfizer/BioNTech COVID-19 vaccine from senior nurse Dilhani Somaweera.Credit: JACK HILL - AFP

Messenger-RNA is a molecule that carries the information embedded in the DNA, which is located in the cell nucleus, to extranuclear ribosomes, which are the molecular machines that build proteins based on the genetic code. When the RNA in the vaccine reaches the body’s cells, it “captures” this mechanism, as does the virus itself. It attaches to ribosomes and makes them produce proteins according to the instructions it carries.

The protein produced by the vaccine is identical to the “spike” protein on the virus, which allows it to invade cells. Cells identify this new protein as foreign and present it on their surface, in order to enable the immune system to identify it as a new threat. This is how immune cells learn to identify the coronavirus spike. When the real virus arrives, these cells already know how to easily eliminate it.

This was the underlying idea which served as the basis for developing this vaccine, which entered clinical trials last March. The drawback of this method is that this new technology has not yet been granted final approval for use in humans (except in Britain), in contrast to other delivery platforms for vaccines being developed by other companies.

Henry (Jack) Vokes, 98, reacts receiving the Pfizer-BioNTech COVID-19 vaccine at Southmead Hospital, Bristol, England, Tuesday Dec. 8, 2020. Credit: Graeme Robertson/AP

Since the first people tested received the vaccine only seven months ago, one cannot exclude with certainty rare long-term side effects. Since the vaccine is given to healthy people, in large numbers, safety requirements are much more stringent in comparison to drugs given to sick people, especially those in critical condition.

But the RNA molecules break down quickly inside cells, and they never come close to the nuclear DNA, where changes could have long-term impact, in some cases even inherited to subsequent generations. In contrast to other vaccine delivery platforms, which are comprised of a virus that has been genetically edited so that it presents a coronavirus protein to the immune system, the liposomes carrying the vaccine RNA are not expected to elicit unexpected negative reactions by the immune system.

In fact, the main concern voiced by experts after the beginning of the clinical trials was that the technology would not be sufficiently effective in order to bestow significant protection. These concerns were largely dispelled when the third-phase trial results were published.

A nurse prepares to administer the Pfizer-BioNTech COVID-19 vaccine to patient Trixie Walker at the Northern General Hospital in Sheffield, Yorkshire.Credit: ANDY STENNING - AFP

This phase included tens of thousands of people and showed over 90 percent efficiency in preventing coronavirus symptoms in people receiving the vaccine. What is even more impressive, at least with the Moderna vaccine, is that the vaccine was 100 percent effective in preventing serious illness. None of the people inoculated became seriously ill after contracting the virus.

The remaining question is how effective is the new vaccine in preventing infection, not illness. Will the virus manage to invade the body of inoculated people and multiply to the point at which they become contagious, or will the pre-activated immune system defeat the virus first? Continued monitoring of people who have been vaccinated, as well as other studies on people to be inoculated after approval is given, will resolve this question.

Giving priority to vaccinating populations at risk will significantly reduce serious illness and the burden on hospitals. But until the entire population is vaccinated, people already inoculated will have to continue taking the same precautions that were in force during the pandemic.

Even the vaccine developers at Moderna were surprised by the relative stability of the RNA molecules in their vaccine. This molecule breaks down easily, and vaccines must be transported under a deep freeze. This will complicate even further the logistical challenge of inoculating an entire population. It’s also hard to see how the rate of vaccine production will enable the inoculation of the entire world, even a year from now. To this one may add political, cultural and social challenges that exist in an era in which opposition to vaccination finds fertile ground in the social media.

In face of these challenges, the scientific community’s contribution is limited. A small but vocal minority of academics, some with international reputations, are using their professional reputation to disseminate disinformation regarding the pandemic and the ways to defeat it, including vaccination. They have as much impact as those trying to present the scientific consensus. Thus, it’s possible that in some places, the vaccine will arrive after the pandemic has taken most of its toll.

As Cohen, the president of the Hebrew University, says, “the scientific community is currently building an infrastructure not only for contending with and ending the current pandemic, but also for easing the fight against the next one, which will arrive at an unknown time. But we know that it will.” Dozens of years of investment in science have enabled the development of a vaccine that will save millions of lives and put the world economy back on track.

The knowledge accumulated so far will make fighting the next epidemic easier. From a broader perspective, the scientific community is proving its power in meeting challenges facing the human race, assuming it gets appropriate funding. One can hope that this lesson will not be forgotten the day after the pandemic ends, and that money will be found to enable scientists to find solutions to future challenges, including ones that don’t take the form of a microscopic virus.