Miami-Dade 'not over the hill' on coronavirus but hospitalizations are leveling off

The number of inpatients with COVID-19 at Miami-Dade County’s hospitals has leveled off at about 650 to 700 each day for the past two weeks as the county begins a gradual reopening starting with marinas, parks and golf courses.

But with Miami-Dade still outpacing the rest of the state in the rate of new COVID-19 cases and deaths — and epidemiologists warning that it generally takes two to four weeks of dropping numbers to show solid progress against the disease — the novel coronavirus remains a threat in the hardest-hit county in Florida.

“We still have many cases. We’re by no means over the hill yet,” said Mary Jo Trepka, an infectious-disease specialist at Florida International University.

Yet the numbers, especially the hospitalization figures, do offer hope. “We are at a plateau right now,” she said.

Miami-Dade Mayor Carlos Gimenez, who ordered hospitals on April 4 to self-report key metrics daily, is watching hospitalizations, too, as one of the main measures he’s using to help determine when it will be safe to continue loosening restrictions.

Gimenez said hospital activity has been stable for some time, adding that he was encouraged by more recent trends, such as a reduction in calls to Miami-Dade Fire Rescue. Gimenez is a former fire chief for the city of Miami.

“We’re seeing a decrease in the number of COVID-19 cases that they’re responding to,” Gimenez said. “That is an indicator to me that it has for a long time been either plateauing or starting to come down.”

Watching whether hospital admissions for the virus are going up or down is one of the more accurate ways to chart the path of the pandemic in a community, public-health experts say. Unlike testing, which might not be readily available and might have results delayed by days, hospitalization numbers show in real time how many people are still becoming severely ill with COVID-19.

“Whether you have access to testing or not, if you’re sick as stink, you go to the hospital,” said Michael Lauzardo, chief of the University of Florida College of Medicine’s division of infectious diseases.

Florida’s health department collects and reports county and statewide hospitalization data for patients with COVID-19. But the state’s number is a count of all cases in which an infected person was admitted to a hospital and not the number of people currently in a medical facility for treatment of the disease.

Gimenez’s order requires that hospitals report every day the number of new COVID-19 patients admitted, availability of staffed ICU beds and ventilators, and patients discharged after treatment. The county data is imperfect because not all hospitals report every day, but it provides a clearer picture than the state’s information about conditions in Miami-Dade.

The first few days of reporting, starting on April 5, showed exponential growth, with 409 patients admitted that day and 532 just 24 hours later. By April 7, the number had risen to 596 and started to level off about two days later, the data shows.

The apparent plateau began about two weeks after Miami-Dade issued its countywide stay-at-home order on March 26. Two weeks is also the incubation period for novel coronavirus infection.

The number of patients hospitalized with COVID-19 has not risen beyond the high of 726 on April 21. But hospitalizations in Miami-Dade have not yet declined for a prolonged period, according to the county data.

Last week, researchers from the University of Miami said they believed about 6% of the county population — about 165,000 people — had been infected by the novel coronavirus, according to preliminary results from two rounds of antibody testing across the county.

While that estimate, based on a sample of the population, dwarfs the state’s official case count, Trepka, the epidemiologist, said it would be hard to similarly use hospital data as an alternate method of determining how much of the population has been infected.

That’s because scientists are still learning about what proportion of people infected show mild or no symptoms, making it hard to say what percentage of cases the hospitalizations actually represent.

“I would say that if the number of hospitalizations is stable, then maybe the number of infections is stable, too,” Trepka said. “If it’s stable, we’re good, but we’re much better when that starts to decline.”

Trepka said public officials have to consider many different data points when considering whether and how much to ease social-distancing measures that are reducing transmission of the coronavirus but also causing significant economic and emotional pain to many.

While Trepka said she would want to see two incubation periods of no new cases — in other words, four weeks — to declare the coronavirus pandemic over, others say a two-week trend of reductions in cases and hospitalizations is sufficient to begin a phased reopening. But the experts do generally agree on one thing: They all want to see a steady downward trend as evidence that the infections are waning.

The lower the numbers are when restrictions ease, the more time public-health officials would have to combat a potential resurgence of the virus, experts also said.

Gregg Gonsalves, an epidemiologist at the Yale School of Public Health, said plateaus can persist much longer than models predict, and the downward trends aren’t usually apparent until weeks later. Look for two weeks of downward trends in hospitalizations as a solid indicator, he said.

“After two weeks, when you’ve been looking at hospital numbers petering out in Miami-Dade over that time, you can say, ‘We’re definitely past the plateauing,’ ” Gonsalves said.

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©2020 Miami Herald

Miami-Dade 'not over the hill' on coronavirus but hospitalizations are leveling off