More than 5 million people in the U.S. have skipped their second vaccine dose, CDC reports

TAMPA, Fla. - Federal health officials said more than 5 million people in the U.S. -- or nearly 8% of those who got their first dose -- have skipped out on getting their second shots of the Pfizer or Moderna vaccine.

Medical experts say a single shot provides a weaker immune response, compared to the complete two-dose regiment, which could mean people are at risk of contracting and spreading the coronavirus.

"If you are fully vaccinated, it is highly unlikely that you are going to be somebody who spreads this virus," said Dr. Amesh Adalja with Johns Hopkins Bloomberg School of Public Health. "You're not even likely to be asymptomatically infected. It doesn't mean it’s 100%, but it is extremely unlikely."

While one dose provides some immunity, it’s not clear how long it will last. Researchers with both Pfizer and Moderna say booster shots will likely be needed after a year for those who’ve received both doses.

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As of Monday morning, more than 8.5 million Floridians have been vaccinated against COVID-19. Among those, 2.7 million received the first dose of a two-shot series. Around 5.2 million completed both doses.

READ: Johnson & Johnson vaccine resumes distribution at Florida FEMA sites

Another 531,000 Floridians have received the single-dose Johnson & Johnson vaccine. That number is expected to rise now that the vaccine is once again available after the CDC voted to resume administering the shot.

On Sunday, FEMA sites across Florida resumed offering the Johnson & Johnson vaccine, including at the Tampa Greyhound Track.