NASHVILLE, Tenn. (WKRN) — As the Delta variant of COVID-19 continues to surge, there is now research being done into creating a third booster for the COVID-19 vaccine.

“The companies that are making the vaccine, Pfizer and Moderna, quite reasonably are out there preparing for the worst,” said Dr. William Schaffner, professor of Infectious Diseases at Vanderbilt University Medical Center. “We are hoping for the best and preparing for the worst.”

While talk of needing a third vaccine shot is raising questions and concerns, Dr. Schaffner says the move is more precautionary than it is necessary.

“At the moment, most of the CDC and the rest of us don’t think we need it yet,” Schaffner explained. “Why? Well, first of all the protection we are getting from the current vaccine keeps extending. It’s up to 9 months, a year… and it’s holding fast.”

If or when that statistic changes, Schaffner says companies like Pfizer want to be ready to react.

“I would love to have an approved booster on the shelf ready to go when and if we need it,” said Dr. Schaffner. “If cases really started to appear frequently — serious cases in people who have been previously vaccinated, or if there were a new variant on the scene that could evade the protection of our current vaccines.”

So far, the Centers for Disease Control and Prevention along with the Food and Drug Administration have said fully vaccinated Americans do not need a booster shot. That directive could change over time.