Skip to main content
You are the owner of this article.
You have permission to edit this article.

Ask A Doc:

A column addressing your most sought after health questions, answered by Harbin Clinic's expert healthcare professionals.

Ask a Doc: How was the COVID-19 vaccine made so quickly, and is it safe?

  • Comments
ask a doc john hostetler

A weekly column addressing your most sought-after health questions, answered by Harbin Clinic’s expert healthcare professionals.

Question: How was the COVID-19 vaccine made so quickly, and is it safe?

Dr. John Hostetler: Many questions are circulating regarding the COVID-19 vaccine and its safety and efficacy. Perhaps the most common question is about the speed at which the two mRNA Pfizer and Moderna vaccines were developed.

Three critical factors led to the unprecedented speed at which these COVID-19 mRNA (messenger RNA) vaccines were approved for use by the FDA. First, mRNA technology had been in development since the mid-2000s, and there were 12 early phase clinical trials in progress or completed by October 2019 for diseases like Ebola, Rabies and influenza. No long-term safety concerns emerged from these studies. Second, mRNA vaccines do not utilize live viruses, so they can be manufactured quickly in large quantities in a cell-free process that does not involve preservatives or materials of animal origin. Third, and perhaps most important, once the developed vaccines were shown to be safe and effective in producing an immune response, the U.S. government provided the financial backing to conduct large scale clinical trials with both Pfizer and Moderna vaccines in July of 2020. Approximately 70,000 volunteers stepped up to participate in the seminal trials proving both long-term safety and efficacy. These studies were at least equal to or exceeded the same FDA standards applied to all other vaccines in common use today. The FDA review process is arguably the most rigorous in the world and utilizes many of our nation’s best scientists to independently review the data.

Receiving the COVID-19 vaccine is the best thing you can do to slow the spread of this virus. Continue to check in with the Department of Public Health and your doctor on when you are eligible to receive the vaccine and when it’s available in your area.

Dr. John Hostetler is a board-certified Infectious Disease physician at Harbin Clinic Infectious Disease. To learn more, visit


Recommended for you