Six months ago the WHO first announced that the coronavirus could spread between people. Now, it has reached almost every country in the world. Though The global scientific machine has jumped into action, but there are still many unanswered questions surrounding the nature of immunity, whether the virus is mutating and how effective a vaccine may be.
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In This Story: Vaccine
A vaccine is a biological preparation that provides active acquired immunity to a particular infectious disease. A vaccine typically contains an agent that resembles a disease-causing microorganism and is often made from weakened or killed forms of the microbe, its toxins, or one of its surface proteins.