WHEN MODELS FAIL: Five weeks after social distancing began, Mass. coronavirus hospitalizations and cases remain high. Why so little improvement?
The disease models of late March suggested we would be well on our way down the backside of the pandemic by now, but given the depressing numbers, it is hard not to feel spirits dipping, while progress feels illusive.
“A lot of the models were a little bit misleading in terms of suggesting that there would be these nice, perfect bell curves,” said Thomas Tsai, a professor in the Department of Health Policy and Management at the Harvard T.H. Chan School of Public Health and a surgeon at Brigham and Women’s Hospital. “And what we are seeing is that, realistically, instead of a peak and then a rapid climb down the mountain, so to speak, there’s more of a plateau, especially when it comes to hospitalizations and deaths, because those are lagged behind development of new cases by a few weeks.”
The climb down from the coronavirus plateau is probably going to be a lot slower and more gradual than the climb up, and along the way we can expect some frustrating stops and starts.
Early disease models published in March had predicted that the peak of the outbreak in Massachusetts would be in mid-April; the real peak was probably closer to the week of April 20, Tsai said. “What is encouraging, though, is that if you think about two weeks ago, three weeks ago, the case counts were rapidly rising and the hospitalizations were rapidly rising,” he said. “It’s a silver lining in the sense that the curve does seem to have flattened and the hospitals in Boston and Massachusetts have been able to create the capacity to be able to take care of the surge of COVID-19 patients.”
That is: If the outbreak raced off in the beginning like a car with the accelerator stuck to the floor, we have managed to stop it from going any faster and hold at a roughly steady speed. Stopping the acceleration prevented the state’s hospital system from being overwhelmed.
The next step is “slowing down or decelerating because the idea is to bring that car to a stop,” Tsai said. “You want to be actively stepping on the brakes and seeing the speed come down every single day. I think that analogy is helpful for thinking about our case-positivity rate as well.”
The daily number of new confirmed coronavirus cases has dropped over the past week, though the lines of the “curve” are painfully jagged.
Neither the models nor the modelers have covered themselves with glory.