Illinois Bends Virus Curve Faster Than Hotspots Yet Fears Surge

(Bloomberg) --

Illinois, among the U.S. states with the most coronavirus cases, may be showing signs of slower Covid-19 spread earlier than other major hot spots, according to a new analysis.

The state, which has reported more than 17,800 confirmed cases, stretched the number of days over which cases double to 7.9 as of April 9 from 2.1 on March 22, data compiled by Rush University Medical Center in Chicago showed.

The so-called implied doubling rate is a key indicator public health officials use to project the number of Covid-19 patients that hospitals can expect to see, as well as how many doctors, nurses, beds, ventilators and masks may be needed and when.

The analysis by Rush, which tracked the growth rate from the day hot-spot states confirmed their 100th cases, found Illinois’s rate of doubling is taking longer than New York, California and Washington state at this stage in its outbreak. The higher the number, the better.

For comparison, 25 days after reporting the first 100 instances, confirmed cases doubled every 6.1 days in New York, every 6.6 days in Washington and every 5.1 days in California, according to Rush.

Mitigation Efforts

“We’ve seen that doubling time is longer and longer,” Bala Hota, a doctor specializing in infectious diseases and Rush’s chief analytics officer, said in a telephone interview. “It’s a positive. This whole conversation is about mitigation. It’s about controlling what’s already here.”

Hota cautioned, however, that the model can change direction if virus clusters develop quickly.

Illinois Governor J.B. Pritzker’s stay-at-home order, which runs through April 30, as well as earlier measures to close schools, restaurants and bars, helped slow the surge of Covid-19 infections, allowed hospitals to prepare, and curbed some strain on the state’s health care system, Hota said.

“We’re hoping we continue to see this change in the doubling time and the next few weeks we start to see something that resembles a peak,” Hota said. He added that Rush is monitoring outbreaks in confined areas such as Cook County Jail.

Black Community

Testing, tracing and how the population can be allowed to ease back into daily activities while preventing a fresh spike in cases all need careful consideration, Hota said.

Even amid positive signals on the growth rate, Illinois faces challenges including a higher rate of infection in the black community. Mortality rates for black coronavirus patients in Illinois are five times higher than for white residents, Illinois Department of Public Health Director Ngozi Ezike said.

At Pritzker’s daily press briefing, Ezike said Illinois is working to serve all its residents and to erase disparities. The state reported the number of confirmed coronavirus cases rose to 17,887, including 596 deaths.

While the curve may be starting to flatten, health-care professionals are still preparing for a surge.

“It’s fair to say that there’s a glimmer of hope,” Benjamin Singer, pulmonary and critical care specialist at Northwestern Memorial Hospital, said in a telephone interview on Friday. Yet he worries that a return to normal routines too quickly may erase gains.”

“Even though we are starting to see our efforts have been effective, it’s not clear how long we are going to maintain this level of curve flattening,” Singer said. “We need to be ready. We don’t want to be caught unprepared. The ideal situation is that all of our contingency plans stay just as plans. I would not feel bad at all for over-planning for this.”

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