The bacterium that causes food poisoning could actually prove a useful ally in the development of better vaccines to ward off a variety of viral diseases such as HIV, smallpox and influenza, claims a University of Michigan study in the January issue of Molecular Pharmaceutics.The researchers developed a new vaccine formulation that uses an unusual protein derived from the Listeria bacterium.Live or weakened viruses are typically used in conventional vaccines to boost the body’s immune response. This new Listeria vaccine formulation uses viral protein components along with the bacterial protein, reducing the chance of accidental viral infection.