Spread Of COVID-19 In Allegheny County Is Slowing, But It's Too Soon To Go Back To Normal

Apr 9, 2020

Some medical experts and government officials say they are "cautiously optimistic" that recent data indicate that the spread of COVID-19 is slowing in Allegheny County and Pennsylvania.

Dr. Mark Roberts directs the Public Health Dynamics Laboratory at the University of Pittsburgh, which is performing epidemiological modeling of the coronavirus. He spoke with WESA health and science reporter Sarah Boden about how close Pennsylvania is to its peak of COVID-19 cases, and when we might be able to return to normal life. 


This transcript has been edited for clarity.

Sarah Boden: The White House often references that University of Washington’s coronavirus modeling, which currently estimates that Pennsylvania’s COVID-19 resource needs—meaning hospital beds and ventilators—will peak on Monday. Does modeling by the Public Health Dynamics Laboratory at Pitt show something similar?

Dr. Mark Roberts: We do show remarkably similar numbers [to the University of Washington] about what the height of the peak would be in Pennsylvania. So for example, the University of Washington model predicts a peak number of hospitalizations of 2,163. Our peak is about 2,000, which is not significantly different.

The thing that our model has been saying very differently than the University of Washington model—which I think it's just that the University of Washington model was not built to talk about this—is what happens when you release social distancing. All the simulations that we have been doing for the state that look really bad, all those really high numbers occur after you turn social distancing off.

Boden: Earlier this week, Pennsylvania Sec. of Health Dr. Rachel Levine said the state has seen a quote “subtle flattening of the curve.” Do you agree?

Roberts: The data that I’ve seen is that [the number of cases] is not rising as fast as some people have feared. But it’s still going up. Even if you do see a flattening of the curve, and even if you see it start to go down, that doesn’t mean that you are out of the woods.

Boden: It seems to me that overall, western Pennsylvania, compared to eastern Pennsylvania, is doing a better job at stemming the spread of coronavirus. But are we actually doing a better job? Or is it just luck that our cases came later and we had more time to implement social distancing?

Roberts: I think you hit both of them right on the head. Sec. Levine and the governor, pretty early on, closed schools and recommended non-essential business closures, and things like that. It’s a fact of life that large urban centers are going to get the disease earlier. That early time when [the virus is] spreading to people and no one really knows it, that’s crucial. 

Boden: When do you think we can ease up on social distancing?

Roberts: What we’re interested in is finding mechanisms by which we could relax social distancing in ways that are as safe as possible. For example, if we could start doing widespread antibody tests, you could find people who are immune and they could go back to work.

The other thing to think about is relaxing the social distancing based on risk factors. So you could imagine relaxing social distancing in younger people, but not older people. Or keeping recommendations for people with [underlying health conditions like] asthma or chronic obstructive pulmonary disease or immune diseases, things like that. 

The other thing, we just don't know enough about is how much seasonal variation there will be in the infectivity of COVID-19. We know, for example, that all of the endemic coronaviruses that kids spread to each other all the time, [those viruses] almost disappear in the summertime and are only seen in the fall and winter. Now, that doesn't mean there's not gonna be another problem in the fall. But at least it gives breathing room to prepare and to have more time to make treatments, or maybe even more time to make a vaccine.

WESA receives funding from the University of Pittsburgh.