December 5th, New Media Special Report According to a report on the American interesting science website on December 1, a new study shows that the novel coronavirus pneumonia may have arrived in the United States in December 2019.
According to the report, researchers from the Centers for Disease Control and Prevention (CDC) analyzed more than 7,000 blood donation samples collected by the American Red Cross in nine states from December 13, 2019 to January 17, 2020, 106 of which were positive for COVID-19 antibodies.
The study was published in the semi-monthly issue of Clinical Infectious Diseases in the United States on Monday local time. The authors of the report said that the findings indicate that “COVID-19 cases may have appeared in the United States in December 2019, before previously recognized”.
The report pointed out that there are signs that the virus spread earlier than people are aware of it. In France, researchers retrospectively tested the hospitalized sample and found that one patient was infected at the end of December 2019. Interesting Science website previously reported that researchers found antibodies to the novel coronavirus in blood samples collected in Italy last September.
The report notes that in the new study, 39 of the 106 positive samples for COVID-19 antibodies were collected from December 13 to December 16, 2019 in California, Oregon and Washington, and 67 from December 30 to 2, 2019. Collected on January 17, 2020 in Connecticut, Iowa, Massachusetts, Michigan, Rhode Island and Wisconsin.
The report said that antibodies against other coronaviruses may produce a “cross-reaction” and show positive results. But when researchers conducted more tests to find out about such cross-reactions, they found that 84 of the 90 samples tested contained antibodies specific to the novel coronavirus.
The authors of the study also used more accurate methods of COVID-19 antibody testing. But even very accurate tests can produce a small number of false positive results. However, the researchers said that the actual number of positive results in the new study exceeded the expected number of false positive results.
The authors of the study said that in general, the finding “is very unlikely that all reaction samples (positive results) will be false positive”. In other words, at least a portion of these positive samples collected between December 2019 and January 2020 are likely to have been previously infected with COVID-19.
However, Dr. George Rutherford, professor of epidemiology and biostatistics at the University of California, San Francisco, said that although researchers have tried to detect antibodies specific to the novel coronavirus, the possibility of “cross-reaction with other coronaviruses” cannot be ruled out.
In addition, due to the limitations of the study, the relevant findings cannot explain the extent of the virus’s transmission at that time.
The authors of the study said that to confirm this discovery, it is necessary to test human tissue, saliva or blood samples at that time to find clues left by the genetic material of the novel coronavirus.
