New clues on the history of the smallpox vaccine virus

Given the fear that the variola virus could be reintroduced to humans in weaponized form, new generations of smallpox vaccines are highly needed. A new study provides fresh insights on the relationship among the vaccinia strains used to eradicate smallpox in the world and indicates that differently than previously thought, the Dryvax virus that led to the second-generation of smallpox vaccine in the USA is closely related to the Brazilian strain and might as well have come from the French and not the British.
Source: ScienceDaily Headlines - Category: Science Source Type: news