[Inactivated vaccines: characteristics and principles of use]

Inactivated vaccines are non infectious, which makes them remarkably innocuous, but implies to repeat their injections, with variable periodicity according to each vaccine, in order to maintain protective immunity. Inactivated vaccines include either complete microbial agents or purified antigenic fractions. The potency of inactivated vaccines is usually reinforced by adjuvants. Although inactivated vaccines induce a strong individual protective immunity, their use requires a high vaccine coverage among the target population in order to obtain a good herd immunity necessary to reach ambitious public health objectives such as elimination or eradication of infectious diseases.