When a person is exposed to SARS-CoV-2, their immune system responds by producing antibodies to fight the virus—and those antibodies can be detected in the blood for months after recovery. A positive antibody test, also known as a serological assay, indicates that a person has likely been infected with SARS-CoV-2 at some point in the past, even if they had no symptoms. An antibody test cannot diagnose a current infection.
Healgen’s COVID-19 IgG/IgM Rapid Test Cassette detects two types of antibodies, immunoglobulin G (IgG) and immunoglobulin M (IgM), in just 10 minutes. To use the test, healthcare workers place a small sample of serum or plasma or one drop of blood on a test cassette. Molecules in the test kit bind to any antibodies specific to the virus. If antibodies are present, a positive result will appear in the cartridge. Currently, the test is authorized for use in laboratories certified to perform “moderate or high complexity tests.”
Antibody tests that have EUA are preferred for public health and clinical use since their test performance data have been reviewed by the FDA. Healgen’s test offers rapid results with high sensitivity and accuracy. In testing at two sites in China from January to March 2020, the test correctly identified with a 96.7% positive percent agreement the positive samples containing either IgG or IgM antibodies compared to RT-PCR (reverse transcription–polymerase chain reaction) and had a 97.0% negative percent agreement of the negative samples compared to RT-PCR.
Recommendations on the use of COVID-19 antibody tests are changing rapidly as new information becomes available. While researchers currently agree there is not enough evidence to conclude that the presence of antibodies indicates immunity to the virus, these tests are expected to play a crucial role in understanding the virus’s spread and identifying groups at higher risk for infection. The Centers for Disease Control (CDC) regularly updates its guidance on
Using Antibody Tests for COVID-19 as new data emerge.
Healgen Scientific, LLC, (Houston, TX), is a wholly owned subsidiary of Zhejiang Orient Gene Biotech Co., Ltd, based in China.