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 had 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 rapidly evolving epidemic, and were some of the first Covid vaccinations to pass into human trials. The effort paid off when, at the end of last year, vaccines came out Moderna Inc. and the Pfizer Inc./The BioNTech SE partnership was the first to prove effective. However, because the technology is so new, these vaccines are particularly vulnerable to disinformation campaigns designed to dissuade people from taking the photos.
1. How do mRNA vaccines work?
They work in a different way than previous generations of vaccines. Instead of introducing the body to an inactivated or attenuated version of a virus or part of it, they temporarily turn the body’s cells into tiny vaccine factories. They do this using synthesized versions of something called messenger RNA, a molecule that normally carries the genetic coding of a cell’s DNA to its protein manufacturing machines. In this case, the mRNA instructs the body to make the spike protein that Sars-CoV-2 uses to enter cells. This, in turn, stimulates the body to make long-lasting antibodies to the virus. Messenger RNA vaccines are faster to develop than traditional ones because their production does not require growing viruses or viral proteins in living cells. In addition, the mRNA nature makes designing new vaccines relatively easy. In January 2020, it took researchers just a few days to come up with the mRNA sequence used in Moderna’s Covid vaccine.
2. What do we know about their effectiveness?
In the phase 3 study with more than 30,000 participants, Moderna’s vaccine was 94% effective in preventing symptomatic cases of Covid, according to the company’s filing with the U.S. Food and Drug Administration. There were no cases of serious illness in people who received the vaccine, compared to 30 in the placebo group. Pfizer’s vaccine was 95% effective at stopping disease, according to the phase 3 study with more than 43,000 participants results published in the New England Journal of Medicine following the peer-review process, examining research by experts in the same field. Although there were less severe cases in that study, the limited data was consistent with protection against serious disease. Real world results are just starting to roll in, but look good so far. Data from Israel’s largest healthcare organization showed that the injection of Pfizer after two doses was 94% effective against symptomatic Covid and 87% of Covid hospital admissions prevented, according to peer-reviewed published results.
3. What do we know about their safety?
Both vaccines can induce strong reactions, especially after the second injection, including headache, muscle and joint pain and fever. For example, in the Moderna process, after the second dose of the injection, most people under the age of 65 experienced fatigue and muscle pain; about half had chills and 1 in 6 people developed a fever. With both vaccines, these side effects are less common in older adults. After the vaccines were approved for use, officials began to notice rare cases of it severe allergic reactions. One theory is that these are caused by the lipid nanoparticles that coat the vaccines and help to transport them in the body. These events are rare, ranging from 2 to 5 cases per million shots given, according to data through Jan. 18 from the U.S. Centers for Disease Control and Prevention. They can generally be treated with adrenaline, otherwise known as epinephrine; a small minority of cases required intubation. A study of data to February 18 onwards Massachusetts General Hospital suggested a higher rate of severe allergic reactions, approx 2.5 cases per 10,000 shots, but concluded that the overall risk remains “extremely low.” Meanwhile, a separate study from Mass General showed that some people get delayed skin rash after receiving Moderna vaccine. While sometimes dramatic, these rashes aren’t dangerous, the researchers said.
4. Who is spreading misinformation about the vaccines?
Traditional anti-vaccine activists have more and more joined forces with figures on the alt-right, a primarily online political movement based in the US whose members espouse extremist beliefs typically centered on ideas of white nationalism. High-profile conservatives, including Fox News personality Tucker Carlson has doubts about Covid vaccines in general. According to the United States Department of State, there are several online platforms linked to Russian intelligence have spread disinformation about mRNA vaccines; Moderna and Pfizer are US-based companies. A Kaiser Family Foundation Research found that vaccine refusers 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?
- Those steps were skipped in developing and authorizing the vaccines: it is true that the vaccines entered the market in record time, but that is not because no testing steps were skipped. Companies accelerated the process by running some testing steps in parallel, and in the case of Moderna’s vaccine, the US government took financial risks by paying to ramp up production before the results were known.
- The vaccines have never been approved by the FDA: That’s true in the sense that so far the agency has only granted emergency clearance. This is a created a pre-existing mechanism to speed up access to medical countermeasures in the event of a public health emergency such as the Covid pandemic. The The FDA pre-determined that in order to receive approval, Covid vaccines had to be at least 50% effective in preventing disease in large-scale studies and demonstrate safety with two months of follow-up data on trial participants. The vaccines were also screened by a panel of independent advisers. Both Moderna and Pfizer have said they plan to apply for regular approval for the vaccines this year.
- Critics have begun to label mRNA vaccines as a form of gene therapy, insinuating that the shots could somehow alter your DNA: they don’t. Although the messenger RNA they use is a type of genetic material, the vaccines differ from what is commonly thought gene therapy because they do not change the DNA in cells. “They do not affect or interact with our DNA in any way,” the Centers for Disease Control and Prevention said explains. In fact, mRNA molecules in the vaccines, which are short-lived, do not enter the cell nucleus, where DNA is stored, the CDC notes.
- That the lipid nanoparticles in the vaccines may contain antifreeze: that’s not true. Antifreeze contains ethylene glycol, which is poisonous. The lipid contains nanoparticles instead polyethylene glycol, an inert compound found in everyday products such as toothpaste and shampoo and in many medicines, including laxatives.
- That the vaccines could cause antibody-dependent enhancement, or a worse case of illness in those who become ill despite vaccination: this was a theoretical concern when Covid vaccine testing began. There was evidence of this problem in animal studies of some vaccines for this severe acute respiratory syndrome (SARS) caused by a coronavirus related to SARS-CoV-2. According to Stanley Perlman, a coronavirus researcher at the University of Iowa, who was part of the FDA advisory panel that reviewed the vaccines.
- That we don’t know the long-term effects of the vaccines: that’s always the case with new vaccines. But side effects of the vaccine usually appear within the first few months after vaccination, so the FDA insisted on two months of safety data before approving them. Adverse event reports have since discovered no death patterns that would indicate a problem with the vaccines, the CDC says.
- That more side effects have been reported for Covid vaccines than for flu vaccines: that’s not an appropriate or meaningful comparison, says Aaron Kesselheim, a professor of medicine at Harvard Medical School. The number of these reports tends to rise when a treatment or vaccine is in the news, and nothing has been in the headlines more than Covid vaccines. In the US, these reports can be submitted by anyone and is not confirmation that a vaccine has caused an adverse reaction. Given the large numbers that are vaccinated, some unfortunate people will get sick and even die shortly after receiving an injection, regardless of the vaccine.