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Pfizer, Moderna, Johnson & Johnson COVID Vaccine: Which one should you take?

Updated: Mar 14, 2021

2020 came at an unexpected surprise, and this pandemic has significantly affected everyone's lives. But hope has finally arrived at the end of 2020, when Pfizer announced that their COVID vaccine showed 92% effectiveness in their Phase III clinical trials. Soon after Pfizer's announcement, Moderna published their data, also showing that their COVID vaccines are 94.1% effective in their clinical trials. Towards the end of December 2020, healthcare employees, politicians, and other essential workers started receiving these COVID vaccines, and the vaccine administration program has been accelerating since the beginning of President Joe Biden's inauguration. Recently, Johnson & Johnson's COVID vaccine has been released into the market, despite their data showing less effectiveness.

Now that we have three different COVID vaccines circulating in the country, the question becomes: Which vaccine should you take? This article breaks down the specific details and components of each type of vaccine.

How are each vaccine made?

Pfizer & Moderna COVID vaccines share similar technology: both are mRNA-based vaccines. When this mRNA is injected into the muscles, they will be taken up by specialized immune cells in our body called dendritic cells. These dendritic cells will produce a COVID spike protein from these mRNA vaccines, which mimics a key protein component of COVID-19 virus. These COVID spike proteins will artificially "train" your immune cells so that when the real COVID-19 invades our body, our immune cells would effectively eliminate the virus.

Johnson & Johnson COVID vaccine utilizes a different technology called adenovirus vector technology. A weakened version of a cold virus is injected into your muscles; this "virus" lost its ability to replicate inside your cells, but it will still deliver genetic instructions to artificially produce a COVID spike protein that stimulates your immune system.

How effective is each vaccine?

Pfizer's vaccine has been shown to be 92% effective after two shots and 62% effective after the first shot. Moderna's vaccine records at 94.1% effective after two shots, with 28 days apart between first and second shot. In contrast, Johnson & Johnson vaccine was 66% effective against moderate illness and 85% effectiveness against severe conditions.

How is each vaccine administered?

Both Pfizer and Moderna vaccines require two doses, 28 days apart. The first dose serves as an initial "training exercise" for your immune system, while the second dose (aka booster shot) will mount a stronger immune response. People will not receive full protection until they receive the booster shot.

Johnson & Johnson vaccine only requires one dose, unlike Pfizer and Moderna. The protection against moderate to severe COVID-related illness starts about two weeks post-vaccination.

What are some of the side effects of each vaccine?

None of the vaccines contain any additives that can cause strong immune reactions, meaning there is a very low risk of allergic reaction, especially life-threatening anaphylaxis (Only one case of anaphylaxis was documented in 44,000 individuals in clinical trials). The main side effects of each vaccines are: muscle pain at the injection site, flu-like fever, fatigue, and headache.

The immune responses that result from these vaccines are much stronger than those individuals after a natural COVID infection.

So far, it looks like these vaccines show protection from various mutant strains of COVID-19. Altogether, all three vaccines are pretty good. Pfizer and Moderna vaccines require two separate doses, each about 3-4 weeks apart. Johnson & Johnson vaccine only requires one dose, but according to clinical trials, it is less effective. Depending on your schedule, Johnson & Johnson may be more convenient if it requires you to travel long distance to receive the vaccine. I personally received the Pfizer vaccine, and I feel much more confident, knowing that I am fairly protected.

Please consider receiving the vaccine whenever you are eligible. Some people may argue that COVID vaccine was produced way too quickly and have doubts about the long-term effects of the vaccine, especially considering the novelty of the mRNA-based technology. But we are living in a different era, where we either live with the vaccine or live with COVID-19. Unfortunately, COVID-19 will remain with us forever, just like influenza (cold virus). The faster people receive the vaccine, the faster we can reach herd immunity, which would enable the nation to open up schools, movie theaters, amusement parks, etc.

#COVID19vaccine #Pfizer #Moderna #JohnsonJohnson #herdimmunity



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