North Carolina coronavirus cases doubled in six days
At least 3,000 lab-confirmed cases of the novel coronavirus have been reported in North Carolina — a jump of 1,000 cases in just four days.
The state saw its first confirmed case of COVID-19, the disease caused by the novel coronavirus, on March 3. It took 25 days to rise to 1,000 confirmed cases, then eight more days to cross the 2,000-case threshold on April 2. From there, it took four days to jump from 2,000 to 3,000 cases, and 48 deaths.
To put it another way, North Carolina took four weeks to reach 1,500 confirmed cases and six days to double that by reaching 3,000 cases.
“We certainly know there are more,” said associate professor of epidemiology at UNC-Chapel Hill Kimberly Powers. “How many more, is the tricky part.”
The News & Observer is independently tracking confirmed cases of COVID-19 across the state based on reports from state and county health departments. That tally is typically higher than the numbers reported daily by the N.C. Department of Health and Human Services.
DOUBLING TIME
The number of lab-confirmed cases of COVID-19 are just a fraction of the true number of cases there are in North Carolina.
“The best way to think of those is the tip of the iceberg,” said Pia MacDonald, a senior epidemiologist at RTI International and an adjunct associate professor at UNC. “There are so many factors that go into a getting a test that’s positive.”
One way to understand to better understand the outbreak, MacDonald said, is by looking at how quickly cases are multiplying.
In North Carolina, the number of cases is currently doubling every six days. In Mecklenburg, cases are doubling every seven days. In Raleigh, doubling time is 7.5 days, and in Durham, it’s 10.
Cases are doubling every six days in New York City, and 11 in Seattle, according to the New York Times.
“How fast it’s moving in our population is very important,” MacDonald said. “The faster it moves through, the more people will die. We’ve got to keep working on flattening the curve.”
And the more cases grow, MacDonald said, the more likely the demand for hospital beds in the state will exceed the supply.
But even for people who do get tested for COVID-19, there’s a backlog in processing the tests. The state’s COVID-19 dashboard currently indicates that it can take up to nine days for a specimen to be reported.
TRIANGLE AND CHARLOTTE NUMBERS
At least 18 states reached 3,000 confirmed cases before North Carolina, including the neighboring states of Georgia and Tennessee, according to a map from the New York Times tracking data nationally.
The true number of people who have had COVID-19 in North Carolina is likely significantly higher than 3,000, as the N.C. Division of Public Health notified providers on March 23 that those with mild symptoms consistent with the disease did not need to be tested and should instead stay home to recover. That message was re-emphasized in March 29 guidance from the department.
In that same guidance, the Division of Public Health states, “Tracking only lab-confirmed cases is not a reliable or accurate way to understand the pandemic.”
North Carolina could reach between 5,500 and 6,500 confirmed cases by April 15, according to a composite model of COVID-19 projections for the state. The composite combines three separate models from experts at Duke University, the University of North Carolina at Chapel Hill and RTI International, among others.
Aaron McKethan, the CEO of NoviSci, Inc, and a senior policy fellow at the Duke-Margolis Center for Health Policy, likened the projections to hurricane forecasts. But unlike hurricane forecasts, McKethan said, policy decisions made now can shift the strength of the impending storm.
If North Carolina continues social distancing practices, past the late April expiration date, the model projects that about 250,000 people in the state will be infected by June 1. Under that scenario, the composite model projects a roughly 25% chance that the number of patients needing hospital beds statewide will outstrip the available resources.
Alternatively, the model projects that about 750,000 people would become infected if all social distancing measures were lifted when the current order expires. That scenario features a roughly 50% chance that need would outstrip the number of available hospital and intensive care beds statewide, with facilities becoming stressed as soon as Memorial Day.
The North Carolina researchers also found that under the scenario totally lacking social distancing, “surging” the system to add beds would be unhelpful. Adding about 4,000 beds under a 20% surge and 10,400 beds under a 50% surge would only lower the possibility of need outstripping demand by about 2 to 4 percent, they reported.
“If a Category 5 hits, putting the boards on your window won’t make a huge bit of difference,” Mark Holmes, the director of the Cecil G. Sheps Center for Health Services Research and a member of the research team, said during a Monday briefing.
The most effective approach, the modelers reported, is to continue working to increase the supply of beds while also working to keep the virus from spreading, thus limiting the demand for those beds.
“We need to continue to do everything in our power so that fewer people get sick at the same time, while also surging the capacity of our health care system so those that do need hospital care will have it,” Mandy Cohen, North Carolina’s secretary of Health and Human Services, said in a release. “Please stay home now to save lives.”
This story was originally published April 6, 2020 at 6:02 PM.
