Vaccine against Helicobacter pylori?

The burden of illness caused by Helicobacter pylori is considerable, and there is little doubt that a therapeutic vaccine would be very useful. However, the merits of using a prophylactic vaccine to eradicate H. pylori from the human population are debatable in light of arguments that it may act as a beneficial commensal organism for many of its human hosts. With regard to the practical side of designing vaccines against H. pylori, animal models have shown us that both therapeutic and prophylactic vaccines are feasible despite the fact that, as in human hosts, immune responses raised naturally to H. pylori cannot eradicate the infection. Many advances have been made in developing optimal vaccination protocols, and recently the first human trial of a therapeutic vaccine, which showed limited but nevertheless encouraging results, was published. However, a possibly quite serious problem is that prophylactic and perhaps also therapeutic vaccines may themselves cause disease.