Contributed by the C. Kenneth and Dianne Wright Center for Clinical and Translational Research. 

This story was completely revised and updated November 1, 2021.

As the one-year anniversary of the country’s first COVID-19 vaccine approaches, many people in the United States remain unvaccinated.  Many are still unsure about the safety of the vaccines. Were the vaccines rushed? Did speed sacrifice safety? What about the side effects?

Here we explain how the vaccines came about so quickly and why you can trust that the vaccines are safe and effective.

1.  Scientists didn’t start from scratch.

It’s true that the COVID-19 vaccines broke records in their paths to reality. But it’s not because anyone cut corners. Instead, the vaccines benefited from prioritization, urgency and knowledge gained from previous research.

Research into a COVID-19 vaccine didn’t begin with Wuhan, China, or the virus’ rapid spread across the United States. U.S. scientists were already hard at work trying to develop a vaccine for other coronaviruses, such as the ones responsible for SARS (severe acute respiratory syndrome) and MERS (Middle East respiratory syndrome).

By the time COVID-19 came along, scientists had been working on a coronavirus vaccine for decades. They had already been studying the new mRNA technology that was used in the Pfizer and Moderna vaccines. Scientists didn’t begin their research with a blank slate. It was a work in progress.

2. The U.S. government prioritized COVID-19 vaccine development and distribution.

Due to the urgency of the situation — the severity of COVID-19 symptoms, the high death rate and the speed with which the pandemic spread — the U.S. government made COVID-19 vaccine development and distribution a priority.  

The government allocated enormous sums to vaccine development and distribution — including the manufacture of vaccine doses before their approval. This ensured that vaccine would be ready for distribution immediately upon FDA authorization for emergency use.  

3.  Vigorous clinical trials included tens of thousands of volunteers.

To be authorized for emergency use, vaccines must go through a careful clinical trial process that includes several phases addressing safety and effectiveness. The COVID-19 vaccine trials did just that — and they included a large number of participants. There were at least 30,000 people each in the Pfizer and Moderna trials and 43,000 people in the Johnson & Johnson trials. In addition, data safety monitoring boards at the National Institutes of Health monitored every trial and scoured the data for irregularities and safety concerns.

4.  The approval process is rigorous.

The Food and Drug Administration (FDA) approves vaccines with advice from the Centers for Disease Control and Prevention. Experts in immunology, infectious diseases, public health and other specialties weigh the evidence.

After a vaccine is authorized by the FDA for emergency use, the CDC must still recommend it before anyone can use it. And even after the vaccine is in use, the agencies continue to collect data on the safety and effectiveness of the vaccine and monitor side effects.

5. The reward far outweighs the risk.

More than 414 million doses of COVID-19 vaccine were administered in the United States from December 14, 2020, through October 25, 2021. During this time an enormous amount of real-world clinical experience with the vaccines has proven them to be both safe and effective.

The risks of being infected and dying from COVID-19 greatly outweigh vaccine-related risks. The United States has passed 700,000 deaths from COVID-19 — and many more people who survive infection will have long-term disabling symptoms. The risks of NOT being vaccinated greatly outweigh any potential vaccine side effects — which tend to go away within a couple days and aren’t dangerous.

“The risks of a side effect are tiny compared to other things that we do every day that we don't even think about risk-wise, like driving on Interstate 95,” said F. Gerard Moeller, M.D., Division Chair for Addictions within Psychiatry at VCU Health and director of the C. Kenneth and Dianne Wright Center for Clinical and Translational Research.  

As for the vaccine itself, Moeller compared it to playing the lottery. “You buy tickets for the lottery, even though there's a one in a million chance that you'll win because the risk is small and the benefit is huge. Why not get a vaccine when the likelihood of a benefit is much, much greater than winning a lottery and the risks are just as small?”

Learn how you can get the vaccine.

This article was created with the help of infectious disease experts Gonzalo Bearman, M.D., Kelly Goode, Pharm.D., F. Gerard Moeller, M.D., and Michael Stevens, M.D. It was originally published December 9, 2020. 

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