The present invention provides a polypeptide antigen comprising amino acid sequences derived from adenylate cyclase protein of Bordetella pertussis, comprising (i) an amino acid sequence of a fragment of CyaA, having on its N-terminus an amino acid residue in position between 1132-1166 and having on its C-terminus an amino acid residue in position between 1287-1294, and to its C-terminus fused: (ii) an amino acid sequence of a fragment of CyaA, having on its N-terminus an amino acid residue in position between 1561-1570 and having on its C-terminus an amino acid residue in position between 1680-1681. N-terminally extended derivatives of this sequence are also provided.Said polypeptide antigen is suitable for use in a method of treatment and/or prevention of a disease caused by Bordetella sp., in particular Bordetella pertussis, Bordetella parapertussis, or Bordetella bronchiseptica, and in particular against pertussis or whooping cough disease. The invention further provides a chimeric protein, a polynucleotide encoding the polypeptide antigen or chimeric protein, a vector and a host cell for the production of said polypeptide or protein.
