An antibody test for the novel coronavirus will soon be available

WHEN A NEWMIMGIGIMIGThe EconomistThe Economist Today virus invades the human body, the immune system leaps into action. First to the scene are antibody molecules of a type called immunoglobulin (g). These bind with proteins on a virus’s surface, disabling it and marking it for destruction by cells called macrophages. A few days later the system produces a second type of antibody, immunoglobulin (g), to continue the fight. gs are short-lived. They stick around in the bloodstream for three or four weeks before disappearing. gs, however, are the basis for a much longer-term form of immunity. This can last for many years, or even a lifetime.