Shigella and ETEC are two of the leading bacterial causes of diarrheal diseases worldwide, affecting up to half of travellers to the developing world and causing approximately 200 million cases in children under five years of age in low- and middle-income countries each year. In addition to a high death toll, repeated infections with Shigella and ETEC can also have long-term consequences on children growth and development.
The published manuscript describes the generation and characterization of ShigETEC, a live, attenuated vaccine candidate. The data demonstrates that vaccination with ShigETEC results in broad protection against different Shigella species that is attributed to the removal of the immunodominant and serotype determining LPS O-antigen by genetic modification of the vaccine strain, and the ETEC coverage is achieved by expressing non-toxigenic ETEC toxins by the Shigella vaccine strain. ShigETEC is non-invasive and avirulent, and therefore expected to address the reactogenicity problem experienced in clinical studies with the previous generations of live Shigella vaccines.