A mucosal vaccine for the prevention or treatment of microbial infections is described that is capable of inducing vaccine antigen-specific immune responses in an organism without the addition of a mucosal adjuvant. The mucosal vaccine comprises a composite of a nanogel comprising a hydrophilic polysaccharide having a cationic functional group and a hydrophobic cholesterol added thereto as a side chain and a vaccine antigen. The vaccine is administered via a mucosal route.
