A new study has begun recruiting at the National Institutes of Health (NIH) in Bethesda, Maryland, to determine how many adults in the United States without a confirmed history of infection with SARS-CoV-2, the virus that causes COVID-19, have antibodies to the virus. The presence of antibodies in the blood indicates a prior infection. In this “serosurvey,” researchers will collect and analyze blood samples from as many as 10,000 volunteers to provide critical data for epidemiologic models. The results will help illuminate the extent to which the novel coronavirus has spread undetected in the United States and provide insights into which communities and populations are most affected.
Anthony S. Fauci, MD
“This study will give us a clearer picture of the true magnitude of the COVID-19 pandemic in the United States by telling us how many people in different communities have been infected without knowing it, because they had a very mild, undocumented illness or did not access testing while they were sick,” said Anthony S. Fauci, MD, Director of the National Institute of Allergy and Infectious Diseases. “These crucial data will help us measure the impact of our public health efforts now and guide our COVID-19 response moving forward.”
Investigators will test participants’ blood samples for the presence of SARS-CoV-2 antibodies. To date, reporting of U.S. cases of COVID-19 has mostly relied on molecular tests that determine the presence of the virus in the airways using a noninvasive cotton swab; these tests do not determine whether a person was previously infected with SARS-CoV-2 and recovered.
Investigators will analyze blood samples for anti–SARS-CoV-2 S protein IgG and IgM using an enzyme-linked immunosorbent assay. In blood samples found to contain antibodies against SARS-CoV-2, researchers may perform additional tests to evaluate the volunteers’ immune responses to the virus. These data may provide insight as to why these cases were less severe than those that led to hospitalization.