Testing for work, travel reveals breakthrough COVID cases, experts say

TAMPA, Fla. - Florida now leads the nation in new coronavirus cases. The majority are among the unvaccinated, but some folks who are fully vaccinated are also testing positive for COVID-19.

U.S. Rep. Vern Buchanan is the latest example of a so-called breakthrough case, contracting COVID-19 even though the Congressman is fully vaccinated.  In a statement, Buchanan said this should serve as a cautionary tale, adding "…we must remain vigilant in the fight against COVID-19."

"Most of the stuff that we're seeing in the breakthrough infections are like three days sniffles, summer cold type thing," said Dr. Thomas Unnasch, USF College of Public Health Distinguished Professor.

The CDC says these cases are expected. While the coronavirus vaccines are highly effective, they don’t block every infection.

RELATED: Tampa General beds filling with unvaccinated COVID-19 patients

Unnasch says there has been a recent uptick in breakthrough cases thanks to the Delta variant. It is the most contagious strain we have seen, and the shots do not provide the same level of infection protection against it.

"So, 70% of the people who are getting exposed are not getting infected at all. But the other 30% are picking up mild infections," he explained.

So mild, most people are not even aware they contracted COVID. Most of these breakthrough cases are being detected by routine testing for work or travel.

Health experts say this is further proof the vaccines are working, and are crucial to preventing serious illness.

RELATED: New Florida COVID-19 cases nearly double over last week; positivity rate jumps

"What the vaccines are supposed to do was keep people from getting hospitalized and keep from getting very sick and dying from COVID. That's exactly what the vaccines are doing," said TGH emergency room physician Dr. Jason Wilson.

The CDC stopped counting breakthrough infections in May, and now only track fully vaccinated people who end up in the hospital or die from coronavirus. As of last week, that total sat at 5,492 patients out of the more than 159-million who have been inoculated.

RELATED: COVID-19 becoming ‘pandemic of the unvaccinated’, CDC director says

"You're still very, very well protected with the vaccine," said Unnasch. "You're not going to get really sick as a result of this." 

According to the Florida Department of Health, only 51% of Floridians are fully vaccinated, and experts say a fourth COVID wave is looming.

New cases, hospitalizations and deaths are all on the rise across the state, and almost every patient is unvaccinated.