novel Coronavirus Evidence that the virus may have already arrived in the United States by late December 2019, at least one month before the first reported case in the country, according to a new study Has been added.
Researchers will be working in the United States from January 2 to March 18, 2020 as part of the National Institutes of Health’s All of Us program, a project aimed at collecting health data from diverse populations. We analyzed over 24,000 blood samples collected.
The researchers identified seven participants from five states (Illinois, Massachusetts, Wisconsin, Pennsylvania, and Mississippi). antibody Prior to the first reported cases of COVID-19 in these states, against the new coronavirus SARS-CoV-2. The earliest detection was from a sample collected on January 7 in Illinois.A new discovery is that the virus is as early as December 24, 2019 in Illinois, as it takes about two weeks for a person to develop these antibodies, according to a study published in the journal on Tuesday (June 15). Suggests that it may have been circulating in Clinical infections..
The study gives COVID-19 “more information about the beginning of the US epidemic,” said Dr. Josh Denny, CEO of All of Us and co-author of the study. I am. Said in a statement..
Relation: 20 of the worst fads and pandemics ever
The first confirmed case of COVID-19 in the United States was reported on January 20, 2020, in a Washington state resident who recently traveled to China. However, researchers suspect that the virus arrived in the United States earlier. A previous study by the US Centers for Disease Control and Prevention also found evidence that the virus was present in the United States in December 2019. Live science previously reported..
Still, new research has its limits. A positive antibody test suggests a previous infection with SARS-CoV-2, but it cannot prove that a person has been infected with the virus. For example, a very accurate antibody test will produce a small number of false positive results.
However, researchers have taken steps to eliminate false positives. They used two different antibody tests and the sample had to be positive in both in order to be counted as a positive result. The first test identified 147 samples that were positive for SARS-CoV-2 antibody, while the second test was also positive for only nine. (Two of these samples were collected after the first case of COVID-19 was identified in each participant’s state.)
The sample may contain antibodies to other similar coronaviruses that “cross-react” with this test and give a positive result, but this is rare. None of the 1,000 blood samples collected in the United States from January to March 2019, used as controls for comparison, were tested positive for antibodies to SARS-CoV-2. did.
“All of these nine are unlikely [positive] Individuals are false positives, “the author writes.
It is important to note that the author did not have information about whether those who tested positive had recently traveled. This suggests whether they have been infected within the community or elsewhere. Researchers will follow up with those who test positive and ask about their travel history. According to the New York Times.. They are also planning further research to pinpoint when the new coronavirus first appeared in the United States.
“Probably the exact month of arrival in the United States is still unknown,” Kelly Althof, an epidemiologist and lead author at the Johns Hopkins Bloomberg School of Public Health, told The Times.
Originally published in Live Science.
