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发帖数: 4825 | 2 By Jessica Wang, Lindsay Huth and Taylor Umlauf
March 22, 2020 9:00 am ET
As the coronavirus epidemic spread around the globe, the Centers for Disease
Control and Prevention provided restrictive guidance on who should be
tested, archived pages on its website show. While agencies in other
countries were advising and conducting widespread testing, the CDC, charged
with setting the U.S. standard for who should be tested for the virus, kept
its criteria limited.
A botched initial test batch also meant that tests were slow to be
distributed and in short supply. Now, the Food and Drug Administration has
allowed private laboratories to develop tests, and the CDC relaxed its
criteria. And positive results across the U.S. have poured in.
Now, the CDC has turned over authority to physicians to determine who gets
tested, but the testing rates vary widely by state.
Number of tests performed versus positive cases
0
2,000
4,000
6,000
8,000
⟵ CASES ⟶
0
10,000
20,000
30,000
⟵ TESTS ⟶
Calif.
N.J.
N.Y.
Wash.
U.S.
7.9
South Korea
33.8 tests per case
0
10
20
30
40
⟵ CASES PER 100,000 ⟶
0
50
100
150
200
250
⟵ TESTS PER 100,000 ⟶
Calif.
D.C.
La.
Mass.
Maine
N.J.
N.M.
N.Y.
Vt.
Wash.
Note: Data as of Mar. 20
Sources: The COVID Tracking Project; Korean Centers for Disease Control
Containing a virus requires identifying and isolating those who are infected
, infectious-disease and public-health experts say. “If we would have had a
true understanding of the extent of the disease several weeks ago,
implementation of social-distancing measures could have prevented the
escalation of the disease,” said Neil Fishman, chief medical officer at the
Hospital of the University of Pennsylvania and an infectious-disease
specialist.
New York has the most cases of any state and has conducted the most tests.
But the state has conducted fewer tests per case than the U.S. average,
indicating testing still lags behind the scale of the epidemic. Washington
and California, two other epicenters, conducted relatively more tests per
confirmed case.
Even those states fall short of South Korea’s testing operations. Compared
with South Korea, which has instituted widespread testing, the U.S., has
conducted far fewer. South Korea is testing up to 20,000 people a day at
hundreds of sites nationwide, health officials say.
How did the testing guidelines change?
Initially, the CDC recommended only investigating those who had symptoms and
had recently traveled to Wuhan, China, or made contact with someone who may
have the virus.
As the outbreak worsened, it expanded the criteria for travel history slowly
, but maintained its recommendation that symptoms be present, despite some
cases having mild or no symptoms.
How the CDC criteria for testing evolved
Tests
Cases
0
1,000
2,000
3,000
4,000
5,000
6,000
CDC released details of its test, after the U.S. opted to develop its own
test.
25
First evidence of secondary transmission in U.S. reported.
U.S. declared a public health emergency and ordered to restrict foreign
nationals traveling from China.
Feb. 1
Feb
CDC testing criteria expanded to:
Travelers from the Hubei province, instead of just Wuhan.
Cases where respiratory illness was severe enough to require hospitalization
, if they traveled from China.
5
CDC started to ship testing kits to state labs.
10
CDC tests shipped earlier were found to be faulty.
15
First quarantine of a group of people started when Americans returned from
Diamond Princess cruise ship, which was quarantined in Japan due to an
outbreak aboard.
20
Feb. 28
CDC testing criteria expanded to:
Travelers from China, Italy, Iran, Japan and South Korea, all which the CDC
placed travel restrictions on in the weeks before.
Cases where respiratory illness was severe enough to require hospitalization
, regardless of personal or travel history.
25
First U.S. death reported. FDA began allowing academic hospital labs to
develop and use their own tests.
March
March 5
5
Testing criteria updated to defer to physicians to make call on who to test.
10
WHO declared the virus a global pandemic.
March 12
Testing criteria updated to note that people who are immunocompromised or
have chronic medical conditions should be factored into priorities for
testing.
Trump declares national emergency.
Note: Testing data is based on available reports.
Sources: Wayback Machine (testing criteria dates); CDC (tests, annotations)
; WHO (annotations); AP (annotations); Johns Hopkins Center for Systems
Science and Engineering (cases)
Once the CDC deferred testing evaluations to individual physicians and
rolled out testing widely, early data show a surge in positive cases, so
public-health officials expect a clearer picture of the epidemic’s scale to
emerge. How many tests are being performed is no longer tracked by the CDC.
It is instead relying on states’ reporting. As more tests are conducted,
officials will have a clearer picture of the scale of the epidemic.
A medical lab technician with Advent Health shows the devices used to test
for coronavirus.
PHOTO: CHRIS URSO/TAMPA BAY TIMES/ZUMA PRESS
—Elbert Wang and Betsy McKay contributed to this article. |
