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Kids Often Move Too Fast; COVID-19 Vaccine Production Didn’t

Vaccine development was long underway before the pandemic began.

By Elizabeth Jane Walker

Kids often seem to move at the speed of sound. They tumble, twirl and scramble. They zoom around the house like tiny wrecking balls. And when snow falls, they hurtle down icy hills on toboggans, saucers and sleds.  

But when it came to creating a vaccine to keep kids safe from COVID-19, scientists did not rush. They calmly joined forces to complete a process that had begun long before the pandemic began.


The great thing about these vaccines is that they don’t have the live, attenuated virus like we see with some other vaccines, With COVID-19, there is no live virus. So, you cannot get COVID from the vaccine.

Diego Hijano, MD, Infectious Diseases


Deliberate speed

For many years, researchers have been working to develop vaccines against several types of coronaviruses, including those that cause colds, severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS). For decades, researchers have also been perfecting the messenger RNA, or mRNA technology that would eventually be used in the Pfizer-BioNTech and Moderna SARS-CoV-2 vaccines.

 When COVID-19 appeared in December of 2019, the pandemic united researchers and agencies like no other event in history.

Within a month, scientists had sequenced the genome of SARS-CoV-2, the virus that causes COVID-19. By fall of 2020, clinical trials were underway. And by December of that year, safe and effective vaccines were within reach for adults. After the COVID-19 vaccines were proven safe and effective in these age groups, scientists began clinical trials to use the vaccines in children.

The new vaccines had many appealing attributes.

“The great thing about these vaccines is that they don’t have the live, attenuated virus like we see with some other vaccines,” said Diego Hijano, MDInfectious Diseases. “With COVID-19, there is no live virus. So, you cannot get COVID from the vaccine.”

 Today, more than 7.5 billion vaccine doses have been given worldwide to individuals ages 5 and older. And yet, some people continue to worry about the very aspects that made this modern marvel possible—the speed of development and streamlined production time. 

infographic timeline for mRNA vaccine development

Layers of safety review

The U.S. Food and Drug Administration (FDA) makes sure that the drugs we take are safe and effective.

FDA reviews include a public component. That’s when independent experts review the data and provide advice. Clinical trials also include data safety monitoring boards where experts not involved in the trial review the data. 

The Centers for Disease Control and Prevention (CDC) also provides recommendations and safety processes. U.S. officials share details with European and other regulators as the vaccines continue to be used around the globe. 

EUA and you

In a pandemic, the FDA can adjust its review process to save the most lives. An Emergency Use Authorization (EUA) involves the same standards as for other vaccines. Then, other resources are added to cut through red tape—allowing decisions to occur more quickly than usual. In the case of COVID-19 vaccines, studies involved tens of thousands of people. These studies showed the vaccines to be safe and effective. Data continue to be collected and reviewed by the FDA and others. 

At one point, the CDC and the FDA paused the use of Johnson & Johnson’s Janssen vaccine, which had received an EUA. Officials wanted to evaluate an extremely rare side effect that affected around 7 women 18-49 years of age out of a million who received the vaccine. Once safety was assured, and the analysis showed the benefits of vaccination outweigh the risks, the pause on that vaccine was lifted. 

Other vaccine candidates simply didn’t make the cut. For instance, when clinical trials showed that two potential vaccines did not provide adequate immune responses, the pharmaceutical giant Merck halted its vaccine production efforts.

Safe and effective

According to the CDC, COVID-19 vaccines are part of the most intensive vaccine safety monitoring effort in U.S. history.

It took scientific ingenuity, collaboration and substantial funding to move the vaccines from concept to reality. Today, more than 195 million Americans are fully vaccinated. The FDA and CDC continue to carefully monitor each COVID-19 vaccine for safety concerns.

“There have been multiple layers of review by independent safety and monitoring committees consisting of scientists, doctors and other health care providers from government and private groups,” said James Hoffman, PharmD, St. Jude chief patient safety officer. Some of these systems existed before; some are newer. 

“But, each of them has been created for one reason: To ensure that the vaccines are safe and effective, which will keep us all safe from COVID-19.”