Scientists have developed a quick, sensitive test for antibodies against the novel coronavirus in human blood that could help doctors track a person’s exposure to Covid-19, as well as confirm suspected cases that tested negative by other methods. Because Covid-19 symptoms range from mild to severe, with some people apparently having no symptoms, the number of people who have been infected with the SARS-CoV-2 virus at some point is likely much higher than the number of confirmed cases, the researchers said.
Although more research needs to be done, it is possible that people with antibodies to the virus could be immune to future Covid-19 outbreaks, according to the research published in the journal Analytical Chemistry.
To help identify people with current or past exposure to SARS-CoV-2, the researchers, including those from Southern Medical University in China, wanted to develop a fast, sensitive antibody test.
They based their test on a technique called a lateral flow immunoassay (LFA); a home pregnancy test is an example of this kind of assay.
The team attached a viral coat protein to a specific region on a strip of nitrocellulose, and then added human serum.