Post by Deleted on Apr 26, 2020 10:59:38 GMT -5
THE CORONAVIRUS CRISIS
When Is It Safe To Ease Social Distancing? Here's What One Model Says For Each State
April 25, 20207:01 AM ET
NURITH AIZENMAN
Across the U.S., state leaders are grappling with the challenging decision of when to relax the social distancing restrictions that have helped keep COVID-19 in check.
Already this week, Georgia's governor has allowed businesses such as gyms, hair salons and movie theaters to reopen — despite not meeting many of the White House's guidelines for Phase 1 of reopening. South Carolina's governor has taken a similar tack — including reopening the state's beaches.
And the governors of other states such as Tennessee and Ohio say they will allow their stay-at-home orders to expire next week, with varying degrees of social distancing required beyond that point.
But how should states decide when to reopen? Epidemiologists and other public health specialists warn against moving too fast. They note that the coronavirus is still circulating. Cases could spiral up to catastrophic levels all over again unless proper measures are taken.
The consensus view is that states shouldn't open up unless they have a robust system to detect and quash new flare-ups by testing to see who is infected, tracing their contacts, and isolating and quarantining as needed.
Unfortunately, there's widespread concern that most states will not be ready to launch such a system any time soon because of continued problems with testing capacity, as well as limited staffing at state and local health departments.
So one team of disease modelers — from the University of Washington's Institute for Health Metrics and Evaluation or IHME — has come up with a different standard. They are asking the question: What is the maximum number of new infections that states could handle with their current testing and contact tracing capacity?
IHME's answer: 1 new infection per million people in a given state. They estimate that states with this level of transmission should be able to keep outbreaks from flaring up even after people start mingling again, though the researchers stress that states would still need to limit large gatherings.
IHME's team built a model to forecast when each state will reach that threshold of 1 new infection per million. Their main finding is that very few states are close.
By May 10, just five states are projected to get there — Alaska, Hawaii, Montana, West Virginia and Vermont. Twenty states and the District of Columbia won't reach the threshold until the beginning of June or later. These include two of the states whose governors have been most aggressive about reopening — Georgia and South Carolina. In addition, Ohio is not projected to meet the standard until May 14; Tennessee not until May 20.
For a chart of the projected date for each state, scroll below or click here.
But first several caveats.
Ali Mokdad, a professor of health metrics sciences at IHME, says the team came up with the 1-new-infection-per-million standard based on some surveying they did of the existing capacities of local health departments across the country. But, he says, "it was very difficult for us to be sure. So we made a very conservative estimate." And, he says, already, "states are starting to reach out to us saying, 'I can do more than that, so [instead] can you tell me what your data shows on when we'll reach, for example, two cases per million?' "
On the other hand, Mokdad warns that the bar for opening up might actually need to be raised still higher in light of new research made public Thursday estimating that about 20% of New York City residents have already been infected with COVID-19. That's many times the number of confirmed cases. And it suggests the coronavirus is being spread by people who are asymptomatic to a far greater extent than IHME's team and other modelers have accounted for. "It confused a lot of us," says Mokdad. "We're having long meetings about it."
Among the implications is that a locality where infections are down to 1 per million might nonetheless need far more testing capacity than IHME's current approach suggests because officials will need to ensure that workers returning to jobs in crowded industries — such as meatpacking plants — are not asymptomatic spreaders of the disease. "We have to be very careful of that," says Mokdad.
A final caveat: IHME's model is just one of many that have been created to map the progression of COVID-19, and some other models offer less rosy projections about the trend line of infection rates. In general, models of this sort should not be taken as literal predictions of the future. They can be useful tools for gauging the likely trend line of an emerging disease and the likely impact of various response strategies. But models are inherently subject to error because they are based on numerous assumptions that scientists can only make educated guesses about right now.
When Can States Begin To Relax Social Distancing?
Modelers from the University of Washington are estimating when COVID-19 infections fall below one case per 1 million people. At that point, easing social distancing restrictions may be possible with containment strategies that include testing, contact tracing, isolation and limiting sizes of gatherings.
MAY
MAY 6 Hawaii, Montana
MAY 7 Alaska
MAY 8 West Virginia
MAY 10 Vermont
MAY 11 North Carolina
MAY 13 Maine
MAY 14 Ohio
MAY 16 Idaho, New Hampshire
MAY 18 California
MAY 19 Alabama, Delaware, Illinois
MAY 20 Michigan, Nevada, Tennessee
MAY 21 Indiana, Wisconsin
MAY 23 Louisiana
MAY 24 New Mexico
MAY 25 Wyoming
MAY 26 Colorado
MAY 27 New Jersey, New York, Oregon, Pennsylvania
MAY 28 Washington
MAY 29 Mississippi
MAY 31 Minnesota
JUNE
JUNE 4 District of Columbia, Maryland, Virginia
JUNE 8 South Carolina, Texas
JUNE 9 Connecticut
JUNE 10 Massachusetts, Missouri, Rhode Island
JUNE 14 Florida, Kentucky
JUNE 17 Oklahoma
JUNE 21 Kansas
JUNE 22 Arkansas, Georgia
JUNE 23 Utah
JUNE 26 Arizona, Iowa
JUNE 27 South Dakota
JULY
JULY 3 Nebraska
JULY 19 North Dakota
Source: Institute for Health Metrics and Evaluation at the University of Washington
Credit: Stephanie Adeline/NPR
