You might have heard some people say they prefer one type of vaccine over the other; one brand over others. Before we proceed, let’s set the record straight that all vaccines available effectively keep you from getting COVID-19 and prevent leading to severe illness or, worse, death. All COVID-19 vaccines aim to produce immunity to the SARS-CoV-2 virus and are effective in doing so.
The mRNA (messenger Ribonucleic Acid), viral vector-based, whole virus, and protein subunit are the four types of vaccines available in the country. The general point of these types of vaccines is quite simple; they all instruct the cells in our bodies to develop a distinctive type of protein to trigger bodily immune defense.
While it is crucial to explain the structure of SARS-CoV-2, the virus responsible for COVID-19, in this portion, we will only highlight one part of its structure to understand the topic thoroughly. The S protein or the spike protein, which gives coronavirus its crown-like appearance, allows the virus to enter host cells to cause infection and replicate. It is also the usual target of some, if not all, of the available vaccines we have.
So, what are the differences between these vaccines?
In principle, they all do the same thing – trigger an immune response. One difference between these vaccines is the presence of the virus, whether it be live attenuated or modified. The two types of vaccines, whole virus, and protein subunit, use the actual COVID-19 virus to generate the needed bodily response.
Whole Virus Vaccine (Sinovac, Sinopharm)
The most common brand of vaccines in the country is Sinovac, a whole virus vaccine. It works by using a weakened or modified virus that can still trigger an immune response. When it enters the body, our T cells and antibodies attack the weakened virus. Our specialized memory cells then remember the virus, reminding our body to produce antibodies the next time it reencounters it. Once you receive any of these vaccines, your antibodies will fight the virus when you get infected with the COVID-19 virus.
Protein Subunit (Novavax)
Unlike the whole virus vaccine, this type of vaccine only uses a purified portion of the virus that best stimulates our immune system, specifically, the spike proteins we mentioned above. While it’s relatively the easiest and cheapest to produce among all vaccines in the market, the chances that our body’s defensive cells aimed to attack the virus would notice its presence is lower – triggering a weaker response. With this, subunit vaccines like Novavax would usually contain adjuvants that aim to set off a stronger immune response. Once you receive any of these vaccines, your antibodies will fight the virus when you get infected with the COVID-19 virus.
Not all vaccines use a whole virus or a fragment of it. Like AstraZeneca, Pfizer, Moderna, and Johnson & Johnson use the cells in our bodies to produce antigens.
Viral vector-based Vaccines (AstraZeneca, Johnson & Johnson)
One of the vaccines that don’t require the whole SARS-CoV-2 virus that causes COVID-19 is viral vector vaccines. Arguably the second-most popular vaccine in the country, AstraZeneca, is an example of it. Viral vector-based vaccines use a genetic code from the COVID-19 virus without causing disease. They work by mimicking and copying the spike proteins of COVID-19. After producing spike proteins, they then trigger a strong immune response. Once you receive any of these vaccines, your antibodies will fight the virus when you get infected with the COVID-19 virus.
mRNA (Pfizer, Moderna)
Like the viral vector-based vaccines, mRNA vaccines also involve a genetically engineered code. It contains instructions on how to develop or mimic spike proteins found in COVID-19. Once produced, our body would get rid of the mRNA, leaving no trails behind. The body would then recognize the spike proteins that should not be present in our system. It would then attack the infected cells by building immune response. Once you receive any of these vaccines, your antibodies will fight the virus when you get infected with the COVID-19 virus.
Regardless of their types, all these vaccines work efficiently to protect us from suffering from the severe risks of COVID-19 infection. You do not become magnetic, nor does any of these vaccines alter your genetic makeup. They do not mess with your DNA or become part of it.
While we have dominion over our bodies, and getting vaccines is within our discretion, it is also vital to understand the importance of getting ourselves a certain level of protection. When you decide to do so, take the one that is being offered. We always say that the best vaccine is what’s available right now; in terms of ensuring you and your loved ones are protected, that is true in all accounts.