By Jia Xin
MALAYSIA has seen a spike in COVID-19 cases since September 2020.
In December 2020, our prime minister Tan Sri Muhyiddin announced that Malaysia has secured COVID-19 mRNA-based vaccines from Pfizer-BioNtech, and he would be one of the first few in Malaysia to be vaccinated to convince our people that the vaccine is safe to be used.
Despite so, many are still in fear of the ‘vaccination’ idea, questioning its safety to be used. I would like to shed some light on this matter, in the hope to alleviate the fear and confusion around the COVID-19 vaccines.
What is the difference between conventional vaccine to Pfizer-BioNtech mRNA vaccine?
Conventional vaccine approaches have not been as effective against rapidly evolving disease threats like Ebola, Zika and COVID viruses.
This is because for most conventional vaccines, viruses are first grown in chicken eggs or mammalian cells for months. Then, viruses are harvested with precautions in the laboratory before shipping them around the world.
The whole process is time consuming and complex. For newly emerging and highly transmissible viruses like SARS-CoV-2, of which vaccine is in urgent need, mRNA vaccines could have an impact in these areas due to their rapid development, greater effectiveness and shorter manufacturing time.
The mRNA is made from DNA template in the laboratory, which can be synthesised from an electronic sequence and send worldwide in an instant by computer.
Currently, it takes only about a week to generate an experimental batch of mRNA vaccine. In addition, mRNA vaccines are cheaper to produce and safer for patients compared to traditional vaccines as they are not produced using infectious elements.
The mRNA does not integrate itself into the host genome and the mRNA strand in the vaccine is degraded once the viral protein is made.
How does mRNA vaccine works?
The mRNA vaccines are a new generation of vaccines that educate our cells to produce “harmless piece” of proteins found on virus. After the viral protein pieces are made, our cells break down the mRNA vaccine and get rid of it.
At the same time, our cells display these protein pieces on cell surfaces. Our immune systems recognise these “non-self” proteins and begin building an immune response against them.
Eventually, our bodies have learned to protect our body from the virus and produce memory immune cells that are ready to fight when we encounter the same viral infection again in future.
Are COVID-19 vaccines safe?
Safety trials start in the laboratory, with tests on cells and animals before moving on to human studies, named clinical trials. The Pfizer-BioNtech mRNA-based vaccine, named BNT162b1, is enclosed in a lipid-nanoparticle to facilitate its entry into host cell.
The phase II/III pivotal registration trial of the vaccine was conducted at sites in six countries and involved approximately 43,000 participants. The vaccine efficacy was assessed based on the percentage reduction of disease in a vaccinated group of people compared to placebo group.
Result showed an estimation of 94.6% of vaccine efficacy. Safety data from these participants suggested a favourable safety profile, with the most common solicited adverse reactions being swelling, redness and pain at the injection site, fatigue, headache, muscle pain, chills, joint pain, fever and nausea.
Less than 0.5% of participants developed malaise or lymphadenopathy. The mRNA vaccine from Moderna tested on 30,000 participants showed similar encouraging results.
Overall, due to the favourable safety and efficacy of these two mRNA vaccines, they have been granted Emergency Use Authorisations (EUA) from the US Food and Drug Administration (FDA).
How are COVID-19 vaccines administered?
There are many ways for vaccines to be delivered into our bodies. The selection of administration route can affect the in vivo distribution pattern and expression kinetics of the vaccines.
The PfizerBioNtech mRNA vaccine is administered into individual via intramuscular (IM) route, which is the most common way for vaccine.
Local injection like IM delivers mRNA enclosed in lipid particles to resident/infiltrating antigen presenting cells and relating immune cells in the skin, muscle and lymph nodes, stimulating strong and prolonged local expression.
The possibility for the mRNA vaccine to circulate in the blood and randomly slip into body cells is rare.
Will vaccination cause autoimmune disease/ allergic reactions?
Vaccines are generally safe, with a low incidence of serious systemic adverse events.
To date, no definitive demonstration of a potential role of vaccines in causing autoimmune diseases is available.
Thus, the fear of autoimmune diseases shouldn’t restrict the use of the most important preventive measure presently available against infectious diseases.
The individuals who are prone to develop autoimmune diseases, such as those with known auto-antibodies and the genetic predisposed individuals should be informed of the risks and excluded from the vaccination.
Are big pharmaceutical companies making huge profits?
Many believe big pharma is in league with governments from various countries to profit from the COVID-19 vaccines. But what they don’t see is due to the urgent need for the vaccine, companies, governments and private donors have poured billions of dollars into COVID-19 vaccine projects to make, test and produce them.
Despite so, huge pharmaceutical companies like Johnson & Johnson and Astrazeneca have pledged to sell the vaccine at a price that just covers their costs.
After all, we shouldn’t expect these companies to make vaccines without looking at making profits. Bear in mind these companies took significant risk to develop COVID-19 vaccines really fast and the research and development investments have been significantly huge.
While many people want an injection as soon as possible, others are worried about putting something unknown into their bodies.
Many are also concerned that the progression of the COVID-19 vaccine from laboratory into clinical trial then into human is too fast, when conventional vaccines may take years before getting approval.
The timeline is fast, yes, but we have to think about this unique context that over 200 companies worldwide with unlimited resources and worldwide talents have been focusing on developing COVID-19 vaccines.
The COVID-19 vaccine clinical trials had happened at breakneck speed, but they did not skip any step. All of the works and findings are checked and verified independently. Allergic reactions to vaccines are rare.
For approved vaccine, the ingredients are listed and people with history of significant allergic reactions are not advised to take the vaccine as a precaution step.
Many people lost their family members and friends to the SARS-CoV-2 virus and rapidly increasing unemployment rates and bankruptcy in many businesses are worrying.
Thus, I am pleased that the Pfizer-BioNtech and Moderna vaccines have been approved and Malaysia is taking in these vaccines. I am looking forward to taking it up and for our lives to return to normal again. – Jan 1, 2021
Jia Xin is a research scientist with over 12 years research experience in the area of therapeutic monoclonal antibody and vaccine. She previously worked as a senior research scientist in the UK, at Nottingham University Therapeutic Antibody Centre, Scancell Ltd. and Petmedix Ltd, which are companies focus in antibody and vaccine discovery.
The views expressed are solely of the author and do not necessarily reflect those of Focus Malaysia.
