UB data scientists warn that the community’s ability to maintain the plateau remains sensitive to social distancing
By the University at Buffalo
Early this week, there was a spike in Erie County’s COVID-19 hospitalizations. The number of people hospitalized with the virus in the county reached 258, the highest it has been.
In the context of the global pandemic and how it is playing out in Western New York, that statistic isn’t as grim as it first appeared, according to Peter Winkelstein, M.D., executive director of the Institute for Healthcare Informatics at the University at Buffalo.
“It’s true that on April 27, our COVID-19 hospitalizations spiked to 258,” said Winkelstein, also a clinical professor of pediatrics in the Jacobs School of Medicine and Biomedical Sciences and a physician with UBMD Pediatrics. “So we might still be drifting up, but overall the level of Erie County hospitalizations from COVID-19 has been more or less flat.”
Winkelstein and his team at UB draw their conclusions, which they provide weekly to the Erie County Department of Health and local hospital systems’ medical leadership, from hospitalization data that they analyze every day.
The team includes UB faculty members, postdoctoral fellows and graduate students from the department of biomedical informatics in the Jacobs School and the School of Public Health and Health Professions. It works in close collaboration with the DOH and other organizations in Erie County, including Kaleida Health, Erie County Medical Center, Catholic Health, UBMD, Independent Health Association and HEALTHeLINK.
“Based on data, modeling and science, our local health care systems have stepped up to the challenges created by the COVID-19 pandemic,” said Gale Burstein, M.D., M.P.H., Erie County commissioner of health. “They have worked together to expand acute care and subacute care capacities to meet our community’s hospital needs.”
The key goal of the models that Winkelstein and his team develop for Erie County and local hospital systems is to forecast when and how quickly there might be a surge in COVID-19 hospitalizations so that hospitals and public health can be better prepared.
“The challenges posed by this pandemic require collaboration and innovation from every unit in UB’s academic health center,” said Michael E. Cain, M.D., vice president for health sciences and dean of the Jacobs School. “While faculty physicians care for COVID-19 patients in partner hospitals, UB’s informatics experts are providing our region’s policymakers and hospital administrators with the information they need to make critical decisions in real time.”
The UB models are based on premises drawn from data in the scientific literature that has so far been generated by the experiences of other areas with COVID-19.
The team looks closely at doubling time, which is the amount of time it takes for the number of COVID-19 hospitalized patients to double. Winkelstein said that, after a fairly rapid increase in cases in March, doubling times have slowly decreased.
“We look at an average of the number of cases in the hospitals for the past five to seven days,” Winkelstein said. “There are daily fluctuations. But if you smooth it out, we are about flat. It might be trending up, but if the hospital census grows at all, it will do so much more slowly than we thought it would just a few weeks ago.”
Terminology Change: Discarding ‘Peak’ in Favor of ‘Plateau’
That change in the data is driving a change in the terminology used by Winkelstein and his team. They talk of the “plateau” of cases in Western New York, rather than the “peak” of cases.
“We suggest that people stop talking about the peak,” Winkelstein said. “What’s happening here is that we have hit a plateau, but COVID-19 is not going away. We will be here for a while.”
This plateau is being seen in the number of COVID-19 hospitalizations and the number of COVID-19 patients in the intensive care units. And while Winkelstein emphasized that this is extremely good news, he noted that all of it is contingent on the continuation of social distancing.
“These data give us confidence that we are not following exponential curves, where we would see a surge in hospitalizations, which could blow up the health care system,” he said. “The major explanation is that social distancing in Erie County is working better than anyone expected.”
He noted that, with a plateau, the hospitalizations will continue at a fairly constant pace so long as social distancing is maintained at the current rate.
Small Changes in Social Distancing May Have Big Effects
“Our model shows we are very sensitive to social distancing,” he explained. “It shows that even a small change in social distancing may result in a large change to the hospital census, so it has to be watched very closely.”
A model prepared by the UB team illustrated what might happen if people in the community reduced their social distancing by just 10% by either May 15 or May 31.
“In both cases, we see a large increase in the hospital census,” Winkelstein said, with inpatient numbers potentially exceeding capacity in Erie County.
“We know that the actions that we take today will be reflected in future hospitalization data,” Burstein offered. “Continued social distancing is a vital non-pharmaceutical strategy that will slow community spread of SARS-CoV2 until a safe and effective vaccine is available.”
So, hospital census numbers are the critical piece to watch in the coming weeks, Winkelstein added. “This is why we concentrate on hospital census data. The numbers of patients in the hospitals are the best window on what’s happening in the community and on revealing what proportion of people in the community with the virus end up in the hospital.”
Data from last week and this week show that there are about 1,500 hospital beds occupied in Erie County out of a total of approximately 2,800. The total of intensive care unit beds in the county is about 500 and currently, about 60% of those are occupied.
Winkelstein noted the number of people on ventilators is still high, with about 75% of people in the ICU on ventilators, but there is still capacity in the ICUs.
The critical variable, he added, is still social distancing. “We are sitting on a powder keg. If we lift the lid too quickly, it blows up. But if we are careful and watch closely, we can safely open.”