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How Do Vaccines Get Approved?

doctor giving shot to child
(Image: Getty Images)

As the pandemic continues to impact much of Earth’s daily on goings, more and more people are starting to ask the same big question: When will we see a vaccine for the novel coronavirus SARS-CoV-2? Various statements have been made about when this could be ready, but let's begin by asking the fundamental question here: How do vaccines get approved?

It seems like every day there are a handful of news articles on the status of vaccines. Those articles go on to be shared and the general public begins a dialogue on this topic. There is a lot of stress being placed on a vaccine, so we thought we would take a moment to examine vaccines through the lens of science.

For starters, what exactly is a vaccine? Simply put, a vaccine is a medical intervention that provides acquired immunity from an infectious disease, effectively preventing vaccinated individuals from getting sick. This science has been around for quite a while now.

Vaccines work in two ways. 

One way is for scientists to inject a drastically weakened portion of a disease into our bodies so that we develop antibodies to infection, effectively training our immune system to recognize, defeat, and even remember the infection should there be a need to fend it off again in the future. 

The second way is to send genetic codes to our immune cells and give them specific orders to develop antigens to fight off a particular infection. 

The latter is how scientists are currently approaching the current novel coronavirus pandemic’s vaccine challenge. Currently, there are over 50 vaccines in various phases of trials right now.  

The journey from idea to approved vaccine goes as follows: 

Preclinical trials: Where vaccines are tested in labs on individual cells and animals. 

Phase 1:The vaccine is given to a small group of people to test safety and ensure the desired immune response. 

Phase 2: The expanded trial is where the vaccine is given to hundreds of people split into groups, like children and the elderly for example. 

Phase 3: Efficacy trials are administered to thousands of people and compared to a placebo group that didn't receive the vaccine.

This phase 3 trial also allows for a large enough group of subjects to reveal any rare or unwanted side effects missed by the previous phases. The FDA has said that a COVID-19 vaccine must protect 50% of the vaccinated individuals to be considered effective. As of Tuesday Sept 22nd there were 9 vaccines in Phase 3 trials.

If approved, a vaccine could potentially be administered to the whole world, so proper testing for safety and efficacy - a process that could take months to years - are vital here. This is brand new medical science in action, folks! Until then, scientists still highly suggest maintaining social distancing, wearing a mask in public, avoiding large groups of people, and washing your hands.

While there's a lot of uncertainty and a ton of hard work to go, this is certainly worth a shot.