LOS ANGELES -- U.S. regulators issued new guidance this week shortening the time that people who received Moderna or Pfizer's COVID-19 vaccine have to wait for a booster, and it's different than the ...

Booster shots against the coronavirus have already started rolling out in the U.S. for some people and millions more could be due for them soon. But as breakthrough infections become more common, many ...

If you are looking for a single magical number to tell whether you can be more lax on Covid-19 precautions, sorry, but the level of antibodies in your blood is not going to provide it. Antibodies aren ...

Each week, we answer "frequently asked questions" about life during the coronavirus crisis. If you have a question you'd like us to consider for a future post, email us at [email protected] with ...

Specific antibody deficiency (SAD) is an immune system disorder. It occurs when you have normal levels of antibodies but an insufficient immune response to certain types of bacteria. Antibodies, also ...