COVID-19 vaccine history

Solving the Pandemic Puzzle: How the COVID-19 Vaccines Were Made

How did scientists do it? What happened behind the scenes? Our health experts tell us how it all happened.

Dec. 18, 2020 4   min read

The COVID-19 vaccine arrived in record time, but how did scientists do it? What happened behind the scenes in order for people around the world to begin vaccinations less than a year after the pandemic started? Emil Lesho, DO, Infectious Disease Specialist for Rochester Regional Health, tells us how it all happened. 

COVID-19 vaccine history

When did work start on the COVID-19 vaccine?

While COVID-19 is new, coronaviruses are not. In fact, scientists have been studying coronaviruses for more than 50 years. They used all of those years of research as a springboard, so in January, about 10 days after the first reported cases in Wuhan, China, scientists uncovered the viral sequence of COVID-19.

The COVID-19 vaccine is a messenger RNA (mRNA) vaccine, which scientists also began researching decades ago. These kinds of vaccines teach our cells how to make a protein that triggers an immune response to protect us from viruses like COVID-19.

In March, the U.S. government launched Operation Warp Speed, an initiative to pull together federal health agencies and pharmaceutical companies to coordinate and fund efforts. The plentiful funding, along with the cooperation of scientists throughout the world, accelerated the vaccine’s timetable.

How does the vaccine work?

The newly approved Pfizer/BioNTech and Moderna COVID-19 vaccines use a small amount of genetic material that teaches cells to make the viruses “spike” protein. Once cells begin copying that spike protein, the immune system starts to defend against the virus.

Scientists were especially interested in messenger RNA vaccines because they can be made with readily available materials and don’t require the use of a live virus. This makes it easier to standardize and manufacture large quantities of a vaccine.

What about testing the vaccine for safety?

In creating a vaccine, researchers go through an exploratory stage, pre-clinical stage, and then clinical development, which is a three-phase process:

  • Phase 1 – Small groups of people receive the vaccine.
  • Phase 2 – The study expands and the vaccine is given to people who are similar to those who are expected to take the vaccine.
  • Phase 3 – The vaccine is given to thousands of people and results are studied.

In Pfizer’s case, Phase 3 of its clinical study showed the vaccine was 95% effective for people who had never had COVID-19, and there were no serious safety concerns. Side effects included pain at the injection site, fatigue, headache, muscle pain, chills, and joint pain. 

Pfizer, like any other pharmaceutical company working on a vaccine, had to show this evidence to the Federal Drug Administration before gaining emergency approval.

The 44,000 trial participants will be monitored for two years to study the long-term effectiveness and safety of the vaccine.

Will there be more COVID-19 vaccines in the future?

Several other pharmaceutical companies are continuing to work through the approval process for their vaccines. You can see the status of these vaccines on our vaccine information page.

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Emil P. Lesho, DO
Infectious Disease
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