Modified Outer Membrane Vesicles as safe, effective, low cost, multivalent vaccines against typhoid and paratyphoid fever and invasive non-typhoidal Salmonella infections

Salmonella are bacteria that cause life-threatening diseases in adults and children. Typhoid fever, paratyphoid fever and invasive non-typhoidal Salmonella (iNTS) infections have a high incidence worldwide. These diseases co-exist in many geographical areas, especially in Low and Middle Income Countries (LMIC). Therefore, a single vaccine against all the major Salmonella infections would be highly desirable. Current vaccines against typhoid fever are safe and immunogenic, but require multiple doses and/or show moderate protective ability and some of them are expensive to produce. No vaccines against iNTS or paratyphoid fever are currently licensed. The aim of the project is to use Modified Outer Membrane Vesicles (mOMV) as multivalent and low-cost vaccines against many strains of Salmonella. mOMV are outer membrane vesicles naturally shed by Salmonella bacteria genetically manipulated to decrease adverse reactions. These vesicles are easy and cheap to produce, strongly immunogenic and protective.