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Etymology: ME, killen + L, vaccinus, of a cow
a vaccine prepared from dead microorganisms, generally used to provide immunization from organisms that are too virulent to be used in the living attenuated state. The immune system reacts to the presence of the pathogen in the same manner, whether the organism is alive or dead. However, immunity produced by a live, attenuated vaccine is usually more effective.
killed vaccineA vaccine consisting of dead but antigenically active viruses or bacteria, which evokes production of protective antibodies without causing disease. Cf Live attenuated vaccine.
kill·ed vac·cine(kild vak-sēn')
One made from dead microorganisms for immunization purposes.
see dead vaccine.