Antibody tests of blood samples in Italy have found evidence of COVID-19 infections as early as September 2019, six months before the first known cases in Italy. However, the US government continues to push the theory that the virus escaped from a Chinese biolab in late 2019.
A new study has found that COVID-19 was circulating in the United States several weeks before the first documented cases were identified, paralleling the first detected cases in China, where the outbreak is commonly believed to have begun. The discovery further undermines the theory that the virus originated in China, as cases in other nations have been detected even earlier.
The study was carried out by researchers from the US National Institute of Health’s “All of Us” program and published in the journal Clinical Infectious Diseases.
According to the study’s abstract, the researchers looked at more than 24,000 blood samples from all 50 US states given between January 2 and March 18, 2020, searching for antibodies against SARS-CoV-2, the virus that causes COVID-19. The human body produces the antibodies in the process of fighting off the infection, meaning if someone has them in their blood, they have already contracted the illness at some time in the recent past.
The study found that in five US states – Illinois, Massachusetts, Mississippi, Pennsylvania and Wisconsin – seven people who gave blood samples had SARS-CoV-2 antibodies. Three were from Illinois and taken on January 7, which was 17 days before the first case was identified on January 24. The other states had one case each, most of which were before the first known cases in those states, according to the NIH.
The first COVID-19 case identified in the US was a Washington state resident who tested positive on January 19, 2020. Since then, the US has suffered 33.6 million known COVID-19 cases and more than 600,000 Americans have died.
“This study allows us to uncover more information about the beginning of the US epidemic and highlights the real-world value of longitudinal research in understanding dynamics of emerging diseases like COVID-19,” Josh Denny, chief executive officer of All of Us and an author of the study, said in an NIH news release. “Our participants come from diverse communities across the US and give generously of themselves to drive a wide range of biomedical discoveries, which are vital for informing public health strategies and preparedness.”