At least six states are seeing an uptick in the daily positivity rate for coronavirus infections. That, according to the top government infectious disease expert, is a warning sign that a virus surge is around the corner.
“This is the thing that is disturbing to me, is that we are starting to see the inkling of the upticks in the percent of the tests that are positive … We know now, from past, sad experience, that’s a predictor that you are going to have more surges,” Dr. Anthony Fauci said on Thursday. The positivity rate is the percentage of positive coronavirus cases found among new tests.
Fauci, the director of the National Institute of Allergy and Infectious Diseases and member of the White House Coronavirus Task Force, wasn’t specific about where those upticks are occurring.
An examination of data from the Coronavirus Resource Center at Johns Hopkins University shows that six states are experiencing an increase in the positivity rate over at least the last week after it had leveled off or was declining: Alaska, Indiana, Hawaii, Minnesota, Montana, and Wisconsin.
Yet not everyone is convinced that new surges are coming.
“It’s possible that we’ll see an increase in cases/deaths in states that have seen their positivity rate go up, but as of now, I don’t think any states are going to see a surge on the level of Florida, Arizona, or Texas back in July,” said data scientist Youyang Gu.
Gu has produced his own models that project COVID-19 trends at the state level. His models do not project a surge in those six states.
But other data gives cause for concern. Rt is a measure of how fast the coronavirus spreads, and when that measure is above one, the virus will continue to spread. All six states currently have an Rt above one.
Projecting a surge is tricky, as states often take different measures against the virus.
“Minnesota is doing an outstanding job in slowing the virus, but it is a formidable enemy,” said David Jacobs, the Mayo Professor of Public Health at the University of Minnesota. “I don’t know what will happen next, in what sense there might be a new surge in cases.”
Jacobs stated that “a surge will occur when there is high opportunity for people to be in contact with the virus, mostly indoors with poor indoor-outdoor air exchange, mostly when there are many people in the setting.”
On July 25, Minnesota Gov. Tim Walz, a Democrat, ordered the wearing of masks in public. A few days later, Minneapolis Mayor Jacob Frey ordered bars to close their indoor areas. That seemed to cause virus cases and hospitalizations to slow in August. Yet the positivity rate has increased over the last two weeks, from about 6% to 7.5%.
Unlike Minnesota, Montana has kept its bars open since the beginning of June. It experienced a surge in cases in early July that began to level off late in that month. The positivity rate has risen from 5.3% to 7.5% over the last 14 days.
Over the last week, Indiana’s positivity rate has inched up from 8.6% to 9.6%. But the Hoosier State has also seen its new cases and hospitalizations level off after rising in July. Shandy Dearth, director of the undergraduate program in epidemiology at Indiana University’s Richard M. Fairbanks School of Public Health, credits the statewide mask mandate imposed in late July.
“We are seeing the highest positivity rates in the rural parts of Indiana that didn’t have a mask mandate until the state mandate was implemented,” she said. “In the public health world, most people would say statewide mandates are the best defense, and the earlier they are implemented, the better.”
She further stated that some mayors in Indiana have closed city streets to allow restaurant owners to set up more outdoor dining. “The more steps leaders can take to keep crowds small and outdoors, the better,” she said.
However, she noted, “This will become more of a challenge as Indiana enters colder months, as we head into winter.”
Indeed, as colder weather eventually forces people to take their socializing indoors, the threat of new surges will likely increase.
