The Food and Drug Administration's Vaccines and Related Biological Products Advisory Committee voted unanimously to recommend a booster shot for Johson & Johnson's COVID vaccine. The panel said that the booster shot should be available to everybody over the age of 18 and can be given two months after the initial injection.

After reviewing data that shows a booster shot increased the efficacy of the vaccine by roughly 20%, one of the committee members suggested they should amend the emergency use authorization to make the vaccine a two-dose series.

"I'm inclined to just consider this a two-dose vaccine. That's how it should probably go forward," said committee member Dr. Michael Kurilla, an infectious disease expert with the National Institutes of Health.

The decision comes one day after the committee recommended a booster shot for Moderna's vaccine. That booster shot, along with one for Pfizer's vaccine, has only been authorized for adults over the age of 65, people who have an increased risk of complications from COVID-19, and those who work in jobs with a high risk of being exposed to the coronavirus.

The FDA has the final say on whether to approve the booster shots. The Centers for Disease Control and Prevention must also approve the decision before the booster shots can be administered. A CDC advisory committee is scheduled to meet next week to discuss the booster shots.