1.3.2 Inactivated vaccines
The pentavalent vaccine used in the EPI in Ethiopia contains five vaccines and is sometimes referred to as DPT-HepB-Hib vaccine. The letters refer to diphtheria-pertussis-tetanus-hepatitis B-Haemophilus influenzae type b.
Whole-cell inactivated vaccines are produced by first growing viruses or bacteria in the laboratory and then inactivating (killing) them with heat or chemicals. Because they are not alive, they cannot cause the disease. The pertussis component of the pentavalent vaccine used in the EPI in Ethiopia is an example. The whole-cell inactivated version of this vaccine contains the Bordetella pertussis bacteria, which cause whooping cough, but they have been killed so that they are no longer harmful.
Even though they cannot cause infection in the immunized person, the infectious agents in an inactivated vaccine are still immunogenic. What does this mean?
They are still capable of causing a strong immune reaction in the immunized person, which usually protects him or her from that particular infection in the future.
1.3.1 Live-attenuated vaccines