Low Test Rates Lead To High Percentages Of Positive COVID-19 Cases In Manatee

May 1, 2020
Originally published on April 30, 2020 1:03 pm

Manatee County has had a disproportionate number of COVID-19 cases and deaths when compared to the rest of the state.

According to the Florida Department of Health, as of Thursday afternoon, 55 people in Manatee County died from COVID-19, the respiratory disease caused by the novel coronavirus. That’s the fourth most in the state. Meanwhile, 580 people have tested positive for the virus which represents a 15.4 % presumptive positive test rate, compared to a statewide rate of 8.8%.

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County officials and public health experts have some ideas as to why those numbers are so high.

First, Manatee County has performed a very low volume of testing. As of Thursday, just 3,629 people have been tested for the virus, representing less than 1% of its population. Secondly, some of the data may be skewed due to coronavirus outbreaks at several of the county’s long-term care facilities and nursing homes.

Dr. Marissa Levine, a professor with the University Of South Florida College Of Public Health says the state has seen a big bump in positive test results in county’s where a significant percentage of tests come from those administered in a confined population such as nursing homes. Additionally, she says high positive test rates often mean a community has not conducted enough screenings.

“The thinking is that if you’re testing a large enough sample, you’re going to have a smaller percent positive,” she said. “The idea is that means you’re finding more people who haven’t been exposed and kind of narrowing in on how much burden of COVID there actually is in a community. If your percentage positives are higher you may not have an adequate sample to capture more of the people who don’t actually have exposure to COVID.”

Levine says it’s not yet clear exactly how much testing is enough but some public health officials suggest that a good guiding principle is that 10% of tests or lower should come back positive.

Manatee County’s lack of testing doesn’t appear to be from a lack of effort.

At a Board of County Commissioners meeting earlier this month, Dr. Jennifer Bencie, Manatee County’s Health Officer reported on difficulties obtaining COVID-19 test kits from the state.  She said in March, she received a phone call from state officials saying 600 testing kits were being sent to Manatee County. A couple of hours later, a follow-up call informed her that 150 of those tests were being redirected to a different county. Two weeks ago, Manatee County received an additional 150 testing kits from the state but they were quickly recalled and deemed unuseable.

Since then, Manatee County Commissioners have expressed growing frustration over the lack of available testing kits.

“We’ve been told these tests are available, but it doesn’t seem to be reality,” said Commission Chair Betsy Benac during a recent board meeting. “We have to reach out to our governor. We have to reach out to our legislators. We need more testing in Manatee County. We’ve got to turn this corner.”

Benac also told her fellow commissioners that she had sent an email to Governor Ron DeSantis about the lack of testing kits.

Commissioner Carol Whitmore texted Senate President Bill Galvano in real time during an April 17 meeting. Soon, 300 kits were provided by the Florida Division of Emergency Management.  

County Commissioners also recently voted to authorize spending up to $100,000 to purchase COVID-19 testing kits from the private market.

The Department of Health in Manatee County is currently conducting its second drive-through testing site at the Bradenton Area Convention Center. Another drive-through specimen collection will also occur May 6-8. 

Additionally, plans are in the works for the state to soon open up a regional testing site for Manatee and Sarasota counties.

On Wednesday, National Guard strike teams from the state arrived in Manatee to test patients and staff at long-term care facilities and nursing homes.

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