The present invention relates to compositions and methods for blocking entry of Shigella into a cell of an animal, to therefore providing protection against, or reduce the severity of Shigella infections. More particularly it relates to the use of the IpaD protein obtained from natural sources and/or through synthesis or recombinant technology, and conjugates thereof to induce neutralizing antibodies having protective activity against several serotypes of Shigella, in particular S. flexneri. The composition of the invention is useful to prevent and/or treat shigellosis caused by a bacterium of the Shigella family.
