Repeats of the tetrapeptide (NANP) of the circumsporozoite protein of P. falciparum have been found to be immunogenic and possibly may act as vaccines against malaria infection. The DNA duplex encoding for eight of the (NANP) repeating unit and two of the (NVDP) unit have been synthesized, cloned and expressed in E. coli as a fused protein. The recombinant protein was shown to be immunogenic and to have the antigenic activity of the circumsporozoite.