避重就轻。最新研究表明2019年12月13至2020年1月19日美国9个州7389个献血者中106个（1.4%)新冠抗体阳性。https :// academic.oup. com/cid/article/72/12/e1004/6012472
Serologic Testing of US Blood Donations to Identify Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2)–Reactive Antibodies: December 2019–January 2020
Sridhar V Basavaraju, Monica E Patton, Kacie Grimm, Mohammed Ata Ur Rasheed, Sandra Lester, Lisa Mills, Megan Stumpf, Brandi Freeman, Azaibi Tamin, Jennifer Harcourt ... Show more
Clinical Infectious Diseases, Volume 72, Issue 12, 15 June 2021, Pages e1004–e1009
It can be difficult to distinguish antibodies that neutralize SARS-CoV-2, the virus that causes COVID-19, from antibodies that fight other coronaviruses, including some that cause the common cold. Researchers in both the NIH and CDC studies used multiple types of tests to minimize false positive results, but some experts say it still is possible their 2019 positives were infections by other coronaviruses and not the pandemic strain.
“While it is entirely plausible that the virus was introduced into the United States much earlier than is usually appreciated, it does not mean that this is necessarily strong enough evidence to change how we’re thinking about this,” said William Hanage, a Harvard University expert on disease dynamics.
Serologic Testing of US Blood Donations to Identify Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2)–Reactive Antibodies: December 2019–January 2020
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes coronavirus disease 2019 (COVID-19), was first identified in Wuhan, China, in December 2019, with subsequent worldwide spread. The first US cases were identified in January 2020.
Methods
To determine if SARS-CoV-2–reactive antibodies were present in sera prior to the first identified case in the United States on 19 January 2020, residual archived samples from 7389 routine blood donations collected by the American Red Cross from 13 December 2019 to 17 January 2020 from donors resident in 9 states (California, Connecticut, Iowa, Massachusetts, Michigan, Oregon, Rhode Island, Washington, and Wisconsin) were tested at the Centers for Disease Control and Prevention for anti–SARS-CoV-2 antibodies. Specimens reactive by pan-immunoglobulin (pan-Ig) enzyme-linked immunosorbent assay (ELISA) against the full spike protein were tested by IgG and IgM ELISAs, microneutralization test, Ortho total Ig S1 ELISA, and receptor-binding domain/ACE2 blocking activity assay.
Results
Of the 7389 samples, 106 were reactive by pan-Ig. Of these 106 specimens, 90 were available for further testing. Eighty-four of 90 had neutralizing activity, 1 had S1 binding activity, and 1 had receptor-binding domain/ACE2 blocking activity >50%, suggesting the presence of anti–SARS-CoV-2–reactive antibodies. Donations with reactivity occurred in all 9 states.
Conclusions
These findings suggest that SARS-CoV-2 may have been introduced into the United States prior to 19 January 2020.
NIH study offers new evidence of early SARS-CoV-2 infections in U.S.
Image of a man and test tubes.
An All of Us team member handles participant samples in a lab.NIH
A new antibody testing study examining samples originally collected through the National Institutes of Health’s All of Us Research Program found evidence of SARS-CoV-2 infections in five states earlier than had initially been reported. These findings were published in the journal Clinical Infectious Diseases. The results expand on findings from a Centers for Disease Control and Prevention study(link is external) that suggested SARS-CoV-2, the virus that causes COVID-19, was present in the U.S. as far back as December 2019.
