covid-19 vaccine

Side Effects and Effectiveness: What's Next After the COVID-19 Vaccine?

How long will the immunity last once you are vaccinated? Experts say only time and further research will tell.

NBC Universal, Inc.

Researchers, doctors and scientists believe the benefits of getting the COVID-19 vaccine far outweigh the risks. 

"The majority of patients who have gotten the COVID vaccine have not experienced side effects, even with the second shot," said Dr. Yvonne Johnson, Chief Medical Officer at South Miami Hospital. 

After the first dose of the Moderna vaccine, Thomas Henderson only had arm discomfort, but he says the second dose side effects were not pleasant.

"About six hours later, I basically had classic cold symptoms, I had a really bad headache, aches and fevers all over and my arm was very sore," Henderson said.

If you have post-vaccination mild symptoms, Dr. Johnson recommends some Tylenol and rest. Symptoms should only last one to two days. 

"What we have found is that once you are vaccinated, people don't die and they don't get severe disease and severe enough to have to go into the hospital and go on a ventilator. What we are not sure of is whether or not it prevents the transmission of coronavirus," Dr. Johnson said.

So how effective is the vaccine after the first and second dose?

About one week after the first dose, experts say you have about 50% protection from the virus. Then about two weeks after the second dose, clinical trials show about 95% immunity.  

"The vaccine doesn't work instantaneously so you are still vulnerable, which is why we tell people that even after you've gotten the vaccine, you need to continue to wear your mask and social distance," Dr. Johnson said.

How long will the immunity last once you are vaccinated? Experts say only time and further research will tell.

"Some of the earliest studies, those Phase 1 studies, started about a year ago so there's a great deal of confidence that we probably have at least a year for the vaccine to provide us some protection," Dr. Johnson said.

Contact Us