A person's immune system develops antibodies when exposed to a pathogen like a virus to fight it off.
Nearly a year after coronavirus changed the existing notion of normalcy as humans had known till then, a recent study has now found Covid-19 infections in the USA dating back to December 2019.
"The findings of this report suggest that SARS-CoV-2 infections may have been present in the U.S. in December 2019, earlier than previously recognised", the paper said.
This discovery adds to evidence that the virus was quietly spreading around the world before health officials and the public were aware, disrupting previous thinking of how the illness first emerged and how it has since evolved.
Specifically, 2% of results collected from California, Oregon and Washington (39 out of 1,912 samples collected from those areas) between December 13 and December 16, 2019 confirmed the presence of the virus.
A study published on Monday by agency researchers identified 106 infections among 7,389 archived blood samples drawn from individuals in nine different states between December 13, 2019, and January 17, 2020.
"These findings also highlight the value of blood donations as a source for conducting SARS-CoV-2 surveillance studies", they said.
The samples analyzed were gathered by the organization during the period from December 13, 2019, through January 17, 2020, from donors who lived in nine different states: California, Connecticut, Iowa, Massachusetts, Michigan, Oregon, Rhode Island, Washington, and Wisconsin. But due to China's misleading reports in the early stages of the pandemic, many have suspected that the virus was likely present in the USA long before the beginning of the year.
"The presence of these serum antibodies indicate that isolated SARS-CoV-2 infections may have occurred in the western portion of the United States earlier than previously recognized or that a small portion of the population may have pre-existing antibodies that bind SARS-CoV-2", the report states. The team also said they can't tell if the COVID-19 cases were community- or travel-associated and that none of the antibody results can be considered "true positives".
