An interactive map shows how overloaded hospitals in the US could get as coronavirus cases grow, region by region

• An interactive map from ProPublica and the Harvard Global Health Institute models how different regions around the US would handle coronavirus outbreaks, depending on the infection rate in their population.
• The maps show that almost no regions have the hospital-bed capacity for significant numbers of patients.
• The maps emphasize the need to "flatten the curve" - to slow the spread of the virus enough to give hospitals time obtain more tests, beds, and ventilators.
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"Flatten the curve" has almost become a rallying cry in the US this week. The phrase refers to efforts to keep people apart to slow the US' surge in coronavirus cases so that the number of sick people won't overwhelm already strained hospitals.

A new interactive map lets users explore what an influx of coronavirus patients would look like in different regions around the country, which have varying hospital bed capacities. The number of patients needing hospital care depends on the population's infection rate,which can be slowed with social-distancing measures.

The map was created by ProPublica, with new data and modeling of hospital capacity from the Harvard Global Health Institute.

Check the map out here.

The data shows that even when the infection rate is slowed, "vast communities in America are not prepared to take care of the COVID-19 patients showing up," in most scenarios, Dr. Ashish Jha, director of the Harvard Global Health Institute, told ProPublica.

How the tool works

Jha led a team of researchers who developed the analysis, and their models are based on current hospital bed capacity - meaning the calculations assume that hospitals won't free up already occupied beds or add more beds. The model also assumes that each coronavirus patient requires 12 days of hospital care on average, based on data from China.

The maps factor in a few variables: regional numbers of hospital beds, estimates of people infected, and time frames. Users can look at the country as a whole or explore a particular US city. (The Harvard Global Health Institute gives the number of hospital beds for every city based on the number of beds at the closest hospitals.)

The map shows the number of infected patients who would need hospital beds in three scenarios: If 20%, 40%, or 60% of the population gets infected by the virus within six months, 12 months, or 18 months.

Epidemiologists have predicted that between 40% and 70% of the population will contract the virus. Approximately 20% of coronavirus patients need to be hospitalized with severe or critical cases.

Scenarios in Los Angeles, California, and South Bend, Indiana

Here's how Los Angeles fares in the scenarios the maps lay out: The city has 19,500 hospital beds, about 66% of which are occupied. That leaves about 6,600 beds open for additional patients (this includes 2,420 beds in intensive-care units, which are needed for the most acute coronavirus cases). The LA region has a population of about 10 million, 12% of whom are over 65 and more vulnerable to the COVID-19.

In a moderate scenario in which 40% of the population is infected over a 12-month period, hospitals there would see an estimated 647,000 coronavirus patients.

That would require 21,600 beds over 12 months - 3.3 times the number of available beds in that time period.

Or take South Bend, Indiana: That city has 1,270 hospital beds, 56% of which are full. That leaves 550 beds open for coronavirus patients, including 150 beds in the ICU.

With a population of 721,000 - 15% of whom over the age of 65 - about 8% of the adult population would need care over a 12-month period in a moderate scenario. That's about 45,100 coronavirus patients, requiring about 1,500 beds - 2.7 times the current number.

On average, the 70 available beds in US ICUs are 4.6 times less than the number needed to care for critical cases.

US coronavirus cases are surging

The coronavirus has killed 129 people in the US, with more than 8,000 cases reported across all 50 states and Washington, DC.

Amid the pandemic, many US hospitals are worried about staffing and supply shortages. Already, the US has suffered from a shortage of testing supplies. Medical providers are struggling to get enough protective equipment like masks, and numbers of ventilators are limited as well. The US Food and Drug Administration has also already identified the first drug shortage caused by the outbreak's effect on the supply chain for pharmaceuticals.

"The incentives of the healthcare system are antithetical to building and maintaining surge capacity," Dr. Matthew Wynia, director of the Center for Bioethics and Humanities at the University of Colorado Anschutz, previously told Business Insider.

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