Why is it likely we'll need COVID-19 vaccines in the future?
While scientists say the current vaccines provide good protection, variants of the coronavirus may bring the need for booster shots down the road. ATLANTA  Less than half of all Americans are fully vaccinated, medical experts are stressing that those who have received their shots will likely need to roll up their sleeves again in the future. With some vaccines, youre one and done. Most children need only one dose of the measles vaccine. A tetanus shot requires a booster every ten years. Were urged to get a flu vaccine every year. Scientists are still unsure how long immunity from a COVID-19 vaccine will last, but all indications are that well need periodic booster shots down the road. They provide great immunity, says Dr. Mark Tompkins of UGAs Center for Vaccines and Immunology. Maybe its only for 5 years or 8 years. If you think about tetanus, fantastic vaccine, you get a boost every 8-10 years to maintain immunity.  Theres also the issue of variants. As the coronavirus multiplies, it occasionally makes mistakes leading to mutant versions. It happens with every virus. Manufacturers of the vaccines available in the U.S. say their shots are proving to be effective against variants of the coronavirus, including the highly contagious Delta variant. Changes in the flu virus are why we have yearly vaccines that are updated to keep up with the changes. Its very easy to change them to respond to a new variation of the virus and maintain safety, says Georgia Techs Dr. M.G. Finn. So far, COVID variants havent strayed too far from the original. Think of shooting at a target. The dominant form of the coronavirus is the bullseye. So far, the variants havent drifted outside of range, so the vaccine can still hit them. If a variant drifts too far and becomes the dominant strain, the vaccines will need updating and well need fresh shots. In this case, it wouldnt be a booster but a new immunization to provide that broader immunity to protect against the drifted mutant viruses, says Dr. Tompkins.