Coronavirus modeling projections for Arizona (updated)


The University of Washington has created an interactive website for projection models for hospital bed use, need for intensive care bed use, need for ventilator use, and deaths due to COVID-19 for all 50 U.S. states and the District of Columbia. See,

The website includes this caveat, “In locations without social distancing measures currently in place, we have assumed they will be in place within seven days of the last model update. If not, the number of deaths and burden on their hospital systems will likely be higher than the model predicts.”

For answers to frequently asked questions about the modeling, click here.

To view the paper with in-depth analysis and a description of the methods used to produce the projections, click here.

Brace yourselves, here are the projection models for Arizona. If this doesn’t convince you to stay home and shelter in place, I don’t know what else will.

Hospital Bed/ICU Bed Use

Screen Shot 2020-04-01 at 7.23.48 AMScreen Shot 2020-04-01 at 7.24.17 AM

Invasive Ventilator Use

Screen Shot 2020-04-01 at 7.32.41 AM

Deaths Per Day

Screen Shot 2020-04-01 at 7.34.11 AM

Total Deaths

Screen Shot 2020-04-01 at 7.36.54 AM
Download the data featured in this visualization in full by clicking here.

For questions about these data, please contact IHME at

UPDATE: Josh Marshall at Talking Points Memo has talked to experts who say these are “rosy” projections which underestimate the effectiveness of social distancing. Rosy Scenarios (excerpt):

I wanted to follow up on that with a link to a twitter thread from Carl Bergstrom, a professor at the University of Washington whose work is at the intersection of biology and mathematical models and computer simulations. (He’s on my Twitter list of experts discussing the COVID-19 Crisis.) You can see his critique here. But the gist is that he has questions both about the methodology of the modeling (beyond my expertise) and also the assumptions that go into it. On the latter front he notes that the assumptions are actually quite optimistic, especially assuming social distancing at Wuhan-like levels of success if not implemented with the same severity.

If you’re interested in his argument read his own words. If you’re not up for that simply note that other very knowledgable people are skeptical of these projections, seeing them as discounting significantly worse scenarios which are possible and perhaps probable.

Given Governor Ducey’s go-slow response to the coronavirus pandemic, professor Bergstrom is probably correct.


  1. Please pay close attention to the assumptions. This model assumes we are isolating ourselves, practicing personal distancing and not circulating. The bad numbers are much higher otherwise.

    • Hence the update re: Carl Bergstrom, a professor at the University of Washington whose work is at the intersection of biology and mathematical models and computer simulations, and his critical analysis.

Comments are closed.