Sunday, March 29, 2020

March 29 Update: US COVID-19 Tests per Day #TestAndTrace

by Calculated Risk on 3/29/2020 06:02:00 PM

I strongly recommend reading this plan from Dr. Scott Gottlieb, Caitlin Rivers et, al.: National coronavirus response: A road map to reopening and an op-ed in the WaPo: Experts converge on plans for easing coronavirus restrictions safely.

We are currently in "Phase I: Slow the Spread". To move to Phase II, the authors suggest:

Trigger for Moving to Phase II

A state can safely proceed to Phase II when it has achieved all the following:
• A sustained reduction in cases for at least 14 days,

• Hospitals in the state are safely able to treat all patients requiring hospitalization without resorting to crisis standards of care,

• The state is able to test all people with COVID-19 symptoms, and

• The state is able to conduct active monitoring of confirmed cases and their contacts.
So Test-and-trace is a key criteria to moving to Phase II.   My current guess is test-and-trace will require around 300,000 tests per day.

When I first started posting this data (thanks to the COVID Tracking Project), testing was so low, that just tracking the number of tests made sense.

The percentage positive is also critical. Unfortunately some states and labs don't report all negative tests, although that is supposed to change soon.

The real key is to have enough tests that the US can test all people with symptoms (even mild), all close contacts of those testing positive (aka Test-and-Trace), healthcare workers and first responders fairly regularly (upon request), staff at retirement communities and nursing homes, and those people that regularly visit those facilities (it is a burden on older people not see their families).

Notes: Data for the previous couple of days is updated and revised, so graphs might change.

Also, I include all tests in the total including pending.

The percent positive excludes the pending tests.

There were 95,484 tests reported over the last 24 hours.

COVID-19 Tests per Day Click on graph for larger image.

This data is from the COVID Tracking Project.

The percent positive over the last 24 hours was 22%.

Testing must continue to be expanded until the percent positive declines to 5% or lower.   This is based on results from South Korea.

Test. Test. Test.