New estimates from researchers at the University of Texas at Austin show how much social distancing it would take to “flatten the curve,” or spread out COVID-19 hospitalizations over time, in 22 Texas metro areas.
The research shows that even if all Texans reduce contact with people outside their households by half, it still wouldn’t be enough to stem a surge of hospitalizations that would overwhelm medical capacity in metro areas this spring and summer.
But Lauren Ancel Meyers, a UT-Austin professor of integrative biology and statistics, projects that extreme social distancing measures — cutting social interactions by at least 90% — could meaningfully flatten the curve.
Experts caution that such predictive models should be taken with a grain of salt, given how much circumstances vary on the ground and the lack of testing, making it difficult to measure the extent of the virus' spread so far. And while the charts below are based on 2019 Texas Department of State Health Services hospital capacity data, officials have been adding hospital beds in facilities across the state in response to the pandemic.
The researchers’ estimates are current as of April 1, one day after Gov. Greg Abbott ordered all Texans to stay at home for the next month unless they are taking part in essential services and activities. Texas schools are closed until at least May 4, but the researchers’ estimates assume that schools will not reopen until the 2020-21 school year begins in August.
Below, you can look up one of 22 Texas metro areas to see how school closures and different levels of social distancing would impact coronavirus hospitalizations there. The estimates consider hypothetical scenarios based on whether residents reduce contact with people outside their households by 0%, 50%, 75% or 90%.
In the metro area, which has residents, the estimates show hospitalizations peaking around without social distancing or school closures . Hospital capacity in this area is estimated at beds.
In this chart, the first curve shows a scenario with no social distancing and no school closures. The second curve shows a scenario in which schools close but Texans do not reduce contact with people outside their households.
Texas already has measures in place that encourage social distancing. The researchers estimate hospitalization numbers in the coming months if people reduce contact with people outside their households by 50% or 75% in addition to school closures.
A best-case scenario would be if all Texans reduced contact with people who live outside their households by at least 90% .
“There is still much we do not know about the virus”
These estimates use demographics and information about how the virus spreads to create scenarios in the various metro areas.
The 22 metro areas included in this study range from 120,000 to 7.6 million residents. Without social distancing or school closures, hospitals would exceed capacity in most areas in the second half of May.
Because cities have enacted orders to limit social distancing, the UT-Austin researchers say flattening the curve and spreading out hospitalizations could be much more plausible. They also say the models are not forecasts.
“There is still much we do not know about this virus ... and even more that we cannot forecast about human behavior in the face of this threat,” Meyers, the lead researcher, said. “The take-home message is not about numbers but about the critical need for proactive social distancing to delay and hopefully prevent unmanageable surges in severe infections requiring hospital care.”
Compare when hospitalizations could peak in each metro area
About the data
Hospitalization estimates were taken from a study authored by UT-Austin researcher Lauren Ancel Meyers and her team. The study uses data from other countries where the virus has spread to estimate transmission rates and its severity for people in different age groups.
Researchers ran thousands of simulations to estimate future weekly hospitalization rates based on the number of confirmed cases in each metro area on April 1. The lines represent the weekly median value for those simulations. The shaded bands represent the highest and lowest number of hospitalizations produced by the simulations, reflecting a measure of uncertainty.
Estimated hospital capacities were taken from the Texas Department of State Health Services’ 2019 annual hospital survey. Population figures in Meyers’ study are based on 2018 estimates of metro areas from the U.S. Census Bureau.
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