[A] new report, published in the journal Clinical Infectious Diseases, bolsters earlier studies indicating the virus entered the country under the radar and may have been spreading in the first two months of 2020, well in advance of warnings to that effect from the Centers for Disease Control and Prevention.
A volunteer in Illinois who gave blood on Jan. 7, 2020 — in a study unrelated to the emergent virus — tested positive for antibodies to SARS-CoV-2, according to the NIH report. It noted that the antibodies typically take 14 days, on average, to develop, and this “suggests the virus may have been present in Illinois as early as December 24, 2019.”
But the CDC did not identify community spread of the virus — meaning, infections unrelated to travel from China — until Feb. 26. The NIH report states that the CDC testing guidelines early in the pandemic had a narrow focus: Only people who had been in contact with a person confirmed to have an infection, or who had traveled to an area known to have coronavirus transmission, were advised to be tested.
Elements of that guidance “may have been in place too long, obscuring the geographic spread of SARS-CoV-2 found in our results.”