After a year that resulted in more than 1.7 million deaths and multiple lockdowns, many people are welcoming the news that COVID-19 vaccines are starting to be given to the public. A widespread vaccination could mean life can return to pre-pandemic normalcy, but this scenario depends on people’s willingness to receive the shot.
Some people are concerned about vaccine safety in general, while others are suspicious of the novelty and fast turnaround of COVID vaccines in particular. We asked 14 experts in immunology, biostatistics and vaccinology whether the COVID-19 vaccines are safe.
Which COVID-19 Vaccines Are Approved and What Does That Mean?
Vaccines, along with all other drugs, shouldn’t be used until a country ‘approves’ them. This approval process is carried out by an independent body in each country or group of countries.
In the United States this is done by the FDA (Food and Drug Administration), in the UK by the MHRA (Medicines and Healthcare products Regulatory Agency) and in the European Union by the EMA (European Medicines Agency).
In order for something to be approved by these authorities, it must demonstrate that it is 1) safe and 2) does what it is intended to do.
There are numerous COVID-19 vaccines that are currently being researched and developed. While some of these vaccines are already in use in Russia and China, only two vaccines are currently approved for use in the US and Canada.
One is a joint effort between Pfizer and BioNTech called ‘BNT162b2’ and one is manufactured by Moderna and is called ‘mRNA-1273’. BNT162b2 is approved in 9 countries around the world, including the UK, and is also authorized by the EMA.
How is a vaccine approved?
In order for the Pfizer and Moderna vaccines to be approved by the aforementioned authorities, they must be proven to be safe. The safety data examined during the approval process covers every step of the vaccine’s journey, from initial experiments in the laboratory to the manufacturing process.
An important part of this data are the clinical studies. All drugs, including vaccines, go through three stages of clinical trials:
- Stage I ~ tests the vaccine on a small group of volunteers (20-80) to make sure it is safe and find the right dose
- Stage II – Find out if the vaccine really works by dividing 100-300 volunteers into two groups and giving one group the vaccine and the other a placebo.
- Stage III ~ randomly divides thousands of volunteers into a vaccine group and a placebo group. Do not tell the volunteers or the doctors who is in which group (this is called making the trial ‘double blind’) and check if the vaccine works and if there are any side effects.
For example, if a trial is unsuccessful, the results show that the vaccine does not actually prevent the disease or cause adverse side effects, the trial will be stopped, and the vaccine will not be approved.
Even after the vaccine is approved, it moves into Stage IV, where it is further monitored and information is collected about side effects. This is important to determine whether there are very rare effects, for example with a chance of 1 in 100,000,000.
For example, two people in the UK had an allergic reaction to the Pfizer vaccine after it was given to thousands. This also sometimes happens in response to flu vaccines, and health professionals are ready to deal with such reactions when they give the shot.
Both people have made a full recovery, but gathering information about this is helpful. For example, the UK has now given precautions to people with severe allergies.
Dr. Olivera Finn of the University of Pittsburgh explains: “All new vaccines will continue to be monitored once they start to become widespread. We are now well connected to the entire world, so a single problem with the vaccine anywhere in the world will lead to give to prompt investigation and changes if warranted. “
What security data are there?
Both the Pfizer and Moderna vaccines have undergone all three clinical trials, and no serious side effects from their vaccines have been found.
For the Pfizer vaccine, 195 people were enrolled in the Phase I study in the US and 456 were enrolled in the Phase II study in Germany. In both studies, no one who received the vaccine had any serious side effects. Pfizer’s Phase III study is published in a peer-reviewed journal and involved more than 40,000 volunteers at 152 sites worldwide.
In this trial, volunteers were divided into two groups. One group received two placebo jabs 21 days apart, and one group the actual vaccination. This means that ultimately 18,566 people received the full 2 doses of the vaccine.
For 14 weeks after the second shot, all 18,366 volunteers were assessed for adverse events, both by surveys and by blood draw. After the second shot, only 0.8 percent of them developed a fever. The most common symptoms were pain at the injection site and sometimes sore muscles and headache.
Professor Rick Kennedy of the Mayo Clinic explains that “the vast majority of the side effects observed were expected and are a direct result of the immune response to the vaccine. Side effects are similar to what has been seen with most other approved vaccines and ores occurring with similar rates and with similar levels of severity (usually mild and moderate). ”No one in the study responded seriously to the vaccine.
Importantly, this phase III study included people from different backgrounds: 49 percent were female and 37 percent were black, African American, or Hispanic. In addition, the study included people who may have a higher level of risk: 35 percent of the participants were obese, 21 percent had at least one coexisting condition, and the median age of the volunteers was 52.
The Moderna vaccine similarly included 120 people in their phase I study and 600 people in their phase II study. Although not all Phase III data is yet available to the public (approving authorities will be given access), it involved 30,000 people of various demographics and no serious adverse events were seen.
All of the above information is freely available for everyone to read. In addition, the regulatory authorities that approved these two vaccines had access to much more data covering not only the clinical trials, but also laboratory and animal studies. This information is often more than 10,000 pages long and is carefully researched by the FDA, MHRA and EMA.
What’s in the COVID Vaccines?
Both Moderna and Pfizer vaccines are RNA vaccines. RNA is the information in the SARS-CoV-2 virus that codes for all the machines of the virus.
Traditional vaccines use a dead or modified version of the virus to cause the body to trigger an immune response so that it learns to recognize this virus and therefore becomes immune to it. RNA vaccines instead use a modified version of the SARS CoV-2 virus RNA.
When the RNA gets into your cells, your cells make their own virus fragments, which then teach your body to become immune like any other vaccine. RNA in itself is not harmful, in fact, your cells are constantly making and using RNA.
As Professor Crotty of the La Jolle Institute of Immunology explains, “At any given moment, a human cell has 5,000+ different RNA messages, and they are all temporary messages, like post-it notes that are torn apart within minutes or hours of being torn apart by the cells are torn apart. read. “
The RNA from the vaccine is broken down within a day after injection. Importantly, the vaccines contain only a small portion of the RNA, “the RNA message is for a single coronavirus protein. It takes 25 different coronavirus proteins to make a coronavirus, so don’t worry. make the RNA make a virus. “
The RNA is packaged in tiny spheres of fats called lipid nanoparticles. These lipids are broken down and eliminated by your cells. The other ingredients are water and some salts and sugars to keep these particles stable.
This technology to deliver RNAs through lipid nanoparticles has not been used for vaccines before. However, drugs that use lipid nanoparticles (called “nanomedicines”) have been used since the 1990s, and to date more than 20 different ones have been approved by the FDA or EMA. Some of these drugs are RNA-based, similar to the RNA vaccines. They are mostly used for cancer and gene therapies.
How come the vaccines were made so quickly?
Vaccines usually take years to develop and produce. The COVID-19 vaccines lasted less than a year. This is for a number of reasons, three of which are explained by Dr. Robert Carnahan of Vanderbilt University Medical Center:
“One, all vaccines … were manufactured ‘in danger’. This means that they were produced before the clinical trials were even completed. This would never happen in a normal situation. Many of these costs were supported by various government organizations in the United States. So distribution could begin as soon as the emergency clearance was obtained.
Second, vaccine developers quickly analyzed data as it surfaced and communicated it in real time with various regulatory agencies. Because of these activities alone, there are often differences from months to years between the different phases of clinical trials.
Third, clinical trial recruitment is often a slow and tedious process. There must be people who are ‘at risk’ for the disease in many different demographics and health categories. Due to the immense size of the pandemic, it was quick to find sufficient and suitable volunteers. “
Importantly, the speed did not affect the clinical studies and safety aspects of the process: “The size, thoroughness and complexity of the clinical studies conducted for the current COVID-19 vaccines were no different from those of traditional clinical studies. These are just as safe as vaccines and interventions developed on much slower timelines. ”- Dr Carnahan says.
A balance between risks
Nothing in medicine is 100 percent safe – you are not taking a medication for a disease you don’t have or a vaccine for a disease that doesn’t exist.
Dr. William Hausdorff of PATH, a global public health nonprofit, explains that “all discussions of ‘safety’ for vaccines (or drugs in general) should begin with discussions of how serious and common is the condition you are trying to prevent. or treat it. If the condition is very minor, even trivial side effects may not be worth it. If the condition is very serious, people will accept much greater possible side effects. “
Every medical procedure is a balance between risk and benefit. Both the Pfizer and Moderna vaccines have demonstrated> 90 percent efficacy in protecting humans against COVID-19 in their phase III clinical studies. This protection against a virus that has so far caused more than 1.7 million deaths worldwide is also an important consideration when considering vaccine safety.
The takeaway
All 14 experts agreed with the scientific consensus that the COVID vaccines approved by the appropriate regulatory bodies, such as the FDA, are as safe as any other vaccine or drug.
Nothing in medicine is risk-free, and the decision to take a vaccine is personal and depends on a person’s individual circumstances.
Article based on 14 expert answers to this question: are the COVID-19 vaccines safe?
This expert response has been published in conjunction with the independent fact-checking platform Metafact.io. Subscribe to their weekly newsletter here.