Streptococcus pneumoniae is the most common cause of community acquired pneumonia. It also results in some two million deaths in children under five and is the major cause of otitis media (ear aches) in the US and Europe. Hence, there is a real need for an effective vaccine against this pathogen. Professor Roy Curtiss and colleagues at Arizona...

High-level expression of genes encoding protective antigens produced by recombinant attenuated Salmonella vaccine strains is desirable to maximize antibody responses to the protective antigen(s). However, high-level expression of protective antigens that are of no benefit to the recombinant attenuated Salmonella vaccine strain causes the strain...