MIAMI (CBSMiami) — The highly contagious Delta variant is fast becoming the dominant strain of COVID-19 in Florida, which may be why the number of total coronavirus cases is on the rise.

(CBS4)

According to the Florida Department of Health, the COVID-19 positivity rate has jumped back up to nearly 8% in Florida.

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In Miami-Dade and Broward, it’s more than 5% and in Monroe County it is more than 9%.

The weekly vaccination rates also came out on Friday.

(CBS4)

Statewide, 58% of people have been vaccinated. The numbers are slightly higher in South Florida.

Miami-Dade has a vaccination rate of 73%, Broward is 66% and Monroe has 68%.

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However, the Centers for Disease Control and Prevention says the Delta variant is already the most common strain of the virus in the U.S. and accounts for nearly 52% of cases.

It’s cause for concern in South Florida, according to Florida International University Infectious Disease Specialist Dr. Aileen Marty.

“Florida’s vaccination rate is not high enough for Herd Immunity,” said Dr. Marty in an email conversation with CBSMiami.com. “Immunity from having had COVID-19 is not long-lived nor as specific or valuable as vaccine immunity, and thus, natural immunity cannot be “added” to vaccine immunity to produce significant Herd Immunity.”

She added, “We have a very few inducements to the use of other public health measures in Florida; thus people’s behaviors are promoting the spread of infection.”

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She is also concerned because the Delta variant is “far more contagious and produces more severe disease, behaviors that drive transmission also drive the production of newer and potentially more dangerous variants, and our cases are rising.”

CBSMiami.com Team