Contains live vaccinia virus , a milder form of variola (smallpox) virus.
Does not contain smallpox vaccine and cannot cause the illness.
After a single vaccination 95% of patients are protected within 10 days, and immunity lasts at least 5 years.
Highly successful vaccine but has toxic effects that could be severe, particularly in populations with immune deficiencies or skin disorders.
Toxic effects are related to the replication competence of the vaccinia virus used in vaccination.
Modified vaccine Ankara (MVA) is vaccine that is not associated with safety concerns.