Heterologous vaccine

A heterologous vaccine (also known as a "Jennerian" vaccine) is a type of live vaccine where one pathogen is introduced in order to provide protection against a different one. The vaccines are pathogens of other animals that either do not cause disease or cause mild disease in the organism being treated.

Examples include:

• historically, Jenner's administration of cowpox (vaccinia) to protect against smallpox (variola);
• the administration of BCG vaccine made from Mycobacterium bovis to protect against human tuberculosis.

Like all live vaccines, it has the advantage that it replicates in the body, and therefore reduces the need for booster shots. It has the disadvantage that a potential pathogen is introduced into the body.

It can be combined with the attenuation strategy in vaccine design.