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Sunday, May 17, 2020

May 17 Update: US COVID-19 Test Results: Test-and-Trace Success for Smallpox

by Calculated Risk on 5/17/2020 05:50:00 PM

From Dr. Bill Foege (former Director of CDC) in the Atlanta Journal-Constitution: Opinion: Lessons of Smallpox eradication and COVID-19

Contact tracing and isolation were hallmarks of the smallpox program with labor-intensive work before computers and smart phones were available for workers. In a single state in India, in May 1974, they reported 1,500 new cases a day. That required 1,500 new investigations each day, with the isolation of cases, the locating of contacts, vaccination of contacts and isolation of those with symptoms until a diagnosis could be made. It required tens of thousands of people simply to act as watch guards of the homes of cases and to vaccinate all visitors. All of this with difficult communications and yet currently we hear that contact tracing is not possible until the numbers of cases are reduced. Of course, the diseases are different. A vaccine and the lack of subclinical cases favored smallpox work. However, the approaches to control are similar. A current problem is that testing remains inadequate months after the problem was defined.
In late April, Dr. Fauci said the US might be able to test 400,000 to 600,000 people per day, and this is the first day in that range.   This might be close to enough to allow test-and-trace.

However, the US might need more than 900,000 tests per day according to Dr. Jha of Harvard's Global Health Institute.

There were 422,024 test results 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 5.0% (red line). The US probably needs enough tests to keep  the percentage positive well below 5%. (probably much lower based on testing in New Zealand).

NOTE: A few states are apparently including antibody tests with virus tests. The Covid tracking project is working to straighten that out.