Hepatitis B is a viral infection that impacts the liver. To test for hepatitis B, a doctor can perform a blood test that detects hepatitis B surface antigens. A positive result indicates a hepatitis B ...

SAN FRANCISCO -- There has been a lot of talk about testing for the coronavirus, but you may not entirely understand what the different tests are for. The coronavirus makes some people sick, some ...

The FDA has issued emergency authorizations to 12 antibody tests for the virus. As federal officials gradually begin reopening the country, expanded testing is central to the conversation. Until now, ...

How do rapid antigen COVID-19 tests work? Why did the US government just pledge to buy 280 million of them? And is that even enough to help curb the spread of the virus? As part of President Biden’s ...

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Yes, the experts agree. If you performed the test correctly, a faint line on a COVID test is still a positive result. "Any ...

Antibodies are disease-fighting proteins that play a crucial role in the immune system. Antibodies recognize infectious invaders, such as bacteria and viruses, and help the body eliminate them.