After a year that resulted in more than 1.7 million deaths and multiple closures, many people welcome the news that COVID-19 vaccines are starting to be given to the public. Widespread vaccination may mean that life can return to the normality of the pre-pandemic, but this scenario depends on the willingness of people to get the sting.
Some people are concerned about the safety of vaccines in general, while others are suspicious about the novelty and rapid turnaround time of COVID vaccines in particular. We asked 14 experts in immunology, biostatistics and vaccination whether the COVID-19 vaccines are safe.
Which COVID-19 vaccines have been approved and what do they mean?
Vaccines, along with all other medicines, may not be used until a country ‘approves’ them. This approval process is carried out in each country or group of countries by an independent agency.
In the US it 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, the EMA (European Medicines Agency).
To approve something through these agencies, it must show that it is 1) safe and 2) do what it is intended to do.
There are numerous COVID-19 vaccines currently undergoing research and development. Although some of them are already used in Russia and China, only two vaccines are currently approved for use in the US and Canada.
The one is a joint effort of Pfizer and BioNTech called ‘BNT162b2’ and one is manufactured by Moderna and called ‘mRNA-1273’. BNT162b2 has been approved in 9 countries worldwide, including the United Kingdom, and it has also been approved by the EMA.
How is a vaccine approved?
In order for the Pfizer and Moderna vaccines to be approved by the above agencies, they must be safe. The safety data examined during the approval process cover each step of the vaccine, from the initial experiments in the laboratory to the manufacturing process.
An important part of this data is the clinical trials. All drugs, including vaccines, go through three stages of clinical trials:
- Phase I ~ test the vaccine on a small group of volunteers (20-80) to check the safe and find the right dose
- Phase II ~ discover if the vaccine really works by dividing 100-300 volunteers into two groups and giving one group the vaccine and the other group a placebo.
- Stage III ~ divides thousands of volunteers randomly into a vaccine group and a placebo group. Do not tell the volunteers or doctors in which group (this is called the double blindness of the experiment) and see if the vaccine works and if there are any side effects.
For example, if a trial is not successful, the results show that the vaccine does not actually prevent the disease or its side effects, the trial is stopped and the vaccine is not approved.
Even after the vaccine has been approved, it moves on to phase IV, where it is still monitored and information on adverse effects is collected. It is important to determine if there are very rare effects, for example with a chance of 1 in 100,000,000.
Two people in the UK, for example, had an allergic reaction to the Pfizer vaccine after it was given to thousands. It also sometimes happens in response to flu vaccines, and health professionals are ready to deal with such reactions if they get a jerk.
Both people have fully recovered, but gathering information on this is helpful, for example, the UK has now issued precautions to people with severe allergies.
Dr Olivera Finn of the University of Pittsburgh explains that “All new vaccines are still monitored as soon as they are widely distributed. We are now well connected with the whole world, so a single problem with the vaccine around the world will be quickly investigated and change if necessary. “
What safety data is there?
Both the Pfizer and Moderna vaccines have all undergone three clinical trials and found no serious side effects from their vaccinations.
For the Pfizer vaccine, 195 people were recruited in the US-based Phase I trial and 456 were admitted in the German Phase II trial. In both trials, no one who received the vaccine had any serious side effects. Pfizer’s Phase III trial was published in a peer-reviewed journal and included more than 40,000 volunteers on 152 websites worldwide.
In this trial, volunteers were divided into two groups. One group received two placebo jabs 21 days apart, and one group had the actual vaccines. This means that 18,566 people eventually received the full 2 doses of the vaccine.
For 14 weeks after the second beat, all 18,366 volunteers were assessed for side effects, both by surveys and blood samples. After the second jab, only 0.8 percent of them got fever. More common symptoms were soreness at the injection site and sometimes sore muscles and headaches.
Professor Rick Kennedy of the Mayo Clinic explains that “the vast majority of the side effects that have been expected are expected and are a direct result of the immune response to the vaccine. Side effects are similar to what has been seen with most others. licensed vaccines and ores occurring at similar doses and with similar severity levels (mostly mild and moderate). “No one in the study had a severe reaction to the vaccine.
An important factor is that this Phase III study included people from diverse backgrounds: 49 percent were female and 37 percent black, African-American, or Hispanic. In addition, the study included people who may be at a higher risk level: 35 percent of the participants were obese, 21 percent had at least one condition, and the median age of the volunteers was 52.
The Moderna vaccine similarly included 120 people in their Phase I trial and 600 people in their Phase II study. Although not all of the Phase III data is yet available to the public (approving agencies gain access), it has included 30,000 people from different demographics and has not seen any serious side effects.
All of the above information is freely available for anyone to read. In addition, the regulatory agencies that have approved these two vaccines have access to much more data covering not only the clinical trials but also laboratory and animal studies. This information is often longer than 10,000 pages and is scrutinized by the FDA, MHRA and EMA.
What’s in the COVID vaccines?
Both the Moderna and Pfizer vaccines are RNA vaccines. RNA is the information in the SARS-CoV-2 virus that encodes all the virus machinery.
Traditional vaccines use a dead or modified version of the virus to create an immune response in the body, so it learns to recognize this virus and therefore becomes immune to it. RNA vaccines rather use a modified version of the SARS-CoV-2 virus RNA.
When the RNA enters your cells, your cells make their own virus fragments, which teach your body to become immune like any other vaccine. RNA in itself is not harmful, in fact your cells make and use RNA all the time.
As Professor Crotty of the La Jolle Institute of Immunology explains: ‘A human cell currently has more than 5,000 different RNA messages, and these are all temporary messages, like post-it notes that are sent within minutes or hours to the cells are torn. read. ‘
The RNA of the vaccine is broken down within a day after injection. It is important that the vaccines contain only a small portion of the RNA: “The RNA message is for a single coronavirus protein. It requires 25 different coronavirus proteins to make a coronavirus, so there is no concern that the RNA is a virus do not make. “
The RNA is packaged in small globules 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 before for vaccines. However, drugs that use lipid nanoparticles (called ‘nanomedicines’) have been in use since the 1990s, and so far more than 20 different ones have been approved by the FDA or the EMA. Some of these medicines are based on RNA, similar to the RNA vaccines. It is commonly used for cancer and gene therapies.
Why were the vaccines made so fast?
Vaccines usually take years to develop and manufacture. The COVID-19 vaccines took less than a year. This is due to a number of reasons, three of which are explained by Dr Robert Carnahan of Vanderbilt University Medical Center:
“One, all the vaccines … were manufactured ‘in danger’. This means that they were produced before the clinical trials were completed. This would never have happened in a normal situation. Many of these costs have been borne by various government organizations in the environment, so the distribution could start as soon as emergency permission was obtained.
Second, vaccine developers quickly analyzed data when it came to light and communicated it to various regulatory agencies in real time. There are often gaps between months and years between the different phases of clinical trials due to these activities alone.
Third, recruiting clinical trials is often a slow and arduous process. There must be people who are ‘at risk’ for the disease in many different demographic and health categories. Due to the large scale of the pandemic, it was quick to find sufficient and suitable volunteers. ‘
It is important that the speed does not affect the clinical trials and safety aspects of the process: “The size, thoroughness and complexity of the clinical trials for the current COVID-19 vaccines were no different from traditional clinical trials. It is so safe such as vaccines and interventions have developed at much slower timelines. ‘- says Dr Carnahan.
A balance of risk
Nothing in medicine is 100 percent safe – you do not take medication for a disease you do not have, or a vaccine against a disease that does not exist.
Dr William Hausdorff of PATH, a global organization for public health care, explains that ‘all discussions about’ safety ‘for vaccines (or medicines in general) should start with discussions about how serious and frequent the condition you are trying to prevent or treat is. If the condition is very minor, it is not even worth trivial side effects. If the condition is very serious, people will accept much greater possible side effects. “
Every medical intervention is a balance between risk and benefit. Both Pfizer and Moderna vaccines have shown> 90 percent efficacy in protecting humans against COVID-19 in their Phase III clinical trials. This protection against a virus that has so far caused more than 1.7 million deaths worldwide is also an important consideration when you consider the safety of vaccines.
The takeaway
All 14 experts agreed with the scientific consensus that the COVID vaccines approved by the right regulatory agencies are just as safe as any other vaccine or medication.
Nothing in medicine is risk-free and the decision to take a vaccine is personal and depends on the individual’s circumstances.
Article based on 14 expert answers to this question: Are COVID-19 vaccines safe?
This expert response was published in partnership with the independent fact-checking platform Metafact.io. Subscribe to their weekly newsletter here.