The difference between antibody and antigen tests for the coronavirus: Who should get them and what do they do?

“Pathogens can be seen directly in specimens from the patient, often using a microscope, or grown in the laboratory over a period of days to weeks,” Stephen Berger, founder of the Global Infectious Diseases and Epidemiology Network, said.
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“In most viral infections, specific antibodies can be detected for months to years following infection — and in many cases well into old age,” says Berger.