Dear Dr. Prescott,
I trust vaccines. Nevertheless, I’m nervous about the Covid-19 vaccine. With all we still don’t know about the virus, how can we be sure it will be safe? As a senior, I know I’m in the group that is at the greatest risk for a bad outcome from the coronavirus, but I worry that I may also suffer the most from vaccine side effects.
Teresa Moyeda, Kingfisher, OK
Dr. Prescott Prescribes
While the vaccines scientists are developing for the virus known as SARS-CoV-2 are new, the science behind them is not.
The roots of vaccination date back more than 500 years and, especially in the last century, we’ve developed a deep understanding of how the immune system functions – and doesn’t. Vaccines work, and there’s overwhelming evidence to support it. We’ve inoculated billions upon billions of people against a host of communicable diseases, so we know even the rarest of side effects.
The SARS-CoV-2 vaccines have moved through the development timeline at an accelerated rate, but scientists are not starting from scratch. Many vaccines had been in the works already in some form for other coronaviruses like SARS and MERS that never reached the global pandemic stage. That gave researchers a jump on a SARS-CoV-2 vaccine, and it helped make the rapid timetable more feasible.
When scientists develop drugs to treat a disease, there’s a certain tolerance for side effects because you’re weighing those against the harm that the condition (think cancer or lupus) might otherwise inflict. With vaccines, there’s no active disease. You’re vaccinating healthy people to prevent illness. As a result, scientists are much less willing to accept adverse consequences.
This extremely low tolerance for side effects, or even potential ones, is a big reason for the pauses we saw in some coronavirus vaccine trials. These shouldn’t be viewed as negative developments; indeed, they are par for the course in the development of any vaccine. Rest assured that in these cases, data safety monitoring boards thoroughly investigate whether a side effect is related to the vaccine. If they find it is, they’ll halt the trials, and that vaccine won’t ever be available to the general public.
The bottom line: Trust the process. When there are SARS-CoV-2 vaccines available to take, you can feel good about getting them.