Photographer: Micah Green / Bloomberg
Photographer: Micah Green / Bloomberg
When it became clear in early 2020 that the Sars-CoV-2 virus posed a pandemic threat, researchers who had explored an innovative way of making vaccines saw an opportunity. Experimental messenger RNA vaccines have been recognized for years for their potential speed and flexibility in a fast-moving epidemic and were some of the first Covid vaccinations to pass human testing. The effort paid off when, at the end of last year, the vaccines from Moderna Inc. and Pfizer Inc./The BioNTech SE partnership was the first to prove effective. Because the technology is so new, however, these vaccines are particularly vulnerable to misinformation campaigns aimed at discouraging people from firing.
1. How do mRNA vaccines work?
They work differently from previous generations of vaccines. Instead of introducing the body into an inactivated or weakened version of a virus or part of it, it temporarily transforms the body’s cells into small vaccine factories. They do this using synthesized versions of something called messenger RNA, a molecule that normally transports genetic coding from a cell’s DNA to its protein-making machines. In this case, the mRNA instructs the body to produce the spike protein that Sars-CoV-2 uses to enter cells. This, in turn, stimulates the body to produce long-lasting antibodies against the virus. Messenger RNA vaccines are growing faster than traditional ones because their production does not require the growth of viruses or viral proteins inside living cells. Also, the modular nature of mRNA makes the design of new vaccines relatively simple. It took only a few days in January 2020 to come up with the mRNA sequence used in the Covid vaccine at Moderna.
2. What do we know about their effectiveness?
In its Phase 3 study which involved more than 30,000 participants, the Moderna vaccine was 94% effective in preventing symptomatic cases of Covid, according to the company’s submission to the US Food and Drug Administration. There were no cases of severe disease in people who received the vaccine, compared with 30 in the placebo group. The Pfizer vaccine was 95% effective in stopping the disease in its phase 3 study, which involved more than 43,000 participants, according to results published in the New England Journal of Medicine after the peer review process, in which research is examined by experts in the same field. Although there were fewer severe cases in this process, the limited data were consistent with protection against severe disease. Real-world results are just beginning to show, but they look good so far. Data from Israel’s largest medical organization found that after two doses, Pfizer’s shot was 94% effective against symptomatic Covid and prevented 87% of Covid hospitalizations, according to the study published results.
3. What do we know about their safety?
Both vaccines can induce strong reactions, especially after the second blow, including headache, muscle and joint pain and fever. For example, in the Moderna trial, after the second dose of the shot, most people under the age of 65 had muscle fatigue and pain; about half had chills, and 1 in 6 people had a fever. With both vaccines, these side effects are less common in older adults. After the vaccines were authorized for use, officials began to observe rare cases of severe allergic reactions. One theory is that they are caused by lipid nanoparticles that cover vaccines, helping to transport them into the body. These events are rare, ranging from 2 to 5 cases per million photos given, according to data as of January 18 from the US Centers for Disease Control and Prevention. In general, they can be treated with adrenaline, also known as epinephrine; a small minority of cases required intubation. A study of data up to February 18 of Massachusetts General Hospital has suggested a higher rate of severe allergic reactions, approximately 2.5 cases per 10,000 photos, but still concluded that the overall risk “remains extremely low.” Meanwhile, a separate study by Mass General showed that some people receive delayed rash after administration of the Moderna vaccine. Although sometimes dramatic, these eruptions are not dangerous, the researchers said.
4. Who spreads misinformation about vaccines?
Traditional anti-vaccine activists have more and more he joined forces with figures on on the other hand, an online political movement based in the United States, whose members support extremist beliefs usually centered on ideas of white nationalism. Conservatives, including The Fox News personality that Tucker Carlson has raised doubts about Covid vaccines in general. According to the US State Department, several online platforms related to Russian intelligence services have spread misinformation about mRNA vaccines; Moderna and Pfizer are US companies. Kaiser Family Foundation The survey found that vaccine deniers are disproportionately dependent on Facebook for their information, while people who want the vaccine are more likely to read newspapers or watch TV news on the network.
5. What do they say?
- These steps have been omitted in the development and authorization of vaccines: It is true that vaccines have arrived on the market in record time, but not because any testing steps have been omitted. The companies accelerated the process by conducting parallel testing steps, and in the case of the Moderna vaccine, the US government took financial risks by paying to prepare production before the results appeared.
- Vaccines have never been approved by FDA: It’s true that the agency has so far only granted emergency use authorization. This is an pre-existing mechanism created to accelerate access to medical countermeasures in the event of a public health emergency, such as the Covid pandemic. The FDA had previously determined that in order to gain authorization, Covid vaccines had to be at least 50% effective in preventing disease in large-scale studies and had to demonstrate the safety of two-month follow-up data for study participants. The vaccines were also checked by a group of independent advisers. Both Moderna and Pfizer have stated that they intend to seek regular approval of the vaccines this year.
- Critics have taken labeling mRNA vaccines a form of gene therapy, insinuating that the shots could somehow alter your DNA: no. While the messenger RNA they use is a type of genetic material, vaccines differ from what is commonly thought to be gene therapy by not altering the DNA inside cells. “Does not affect or interact with our DNA in any way,” Centers for Disease Control and Prevention explain. In fact, mRNA molecules in vaccines, which are short-lived, do not enter the cell nucleus, where DNA is stored, the CDC notes.
- That lipid nanoparticles in vaccines may contain antifreeze: this is not true. Antifreeze contains ethylene glycol, which is toxic. Lipid nanoparticles include instead Polyethylene glycol, an inert compound found in everyday products such as toothpaste and shampoo and in many medications, including laxatives.
- The fact that vaccines can cause antibody-dependent improvement or a more severe case of disease in those who get sick despite inoculation: this was a theoretical concern when testing for Covid vaccines began. There have been indications of this problem in animal studies of vaccines for Severe acute respiratory syndrome (SARS), which is caused by a coronavirus linked to SARS-CoV-2. However, no indication was found in human studies of Covid mRNA vaccines, according to Stanley Perlman, coronavirus researcher at Covid. The University of Iowa, which worked on the FDA’s advisory committee that examined the vaccines.
- That we do not know the long-term effects of vaccines: this is always the case for new vaccines. But the side effects of the vaccine usually occur in the first few months after vaccination, which is why the FDA insisted on two months of safety data before authorizing them. Reports of adverse events since then have not detected patterns of death that would indicate a problem with vaccines, the CDC says.
- That there are more reports of side effects for Covid vaccines than for flu vaccines: this is not an appropriate or meaningful comparison, says Aaron Kesselheim, professor of medicine at Harvard Medical School. The number of these reports tends to increase when a treatment or vaccine is in the news and nothing has been more in the headlines than Covid vaccines. In the US, these reports can be submitted by anyone and does not constitute confirmation that a vaccine has caused an adverse event. Given the large number that is inoculated, some unhappy people will get sick and die shortly after being shot, regardless of the vaccine.