The present invention relates, in part, to a purified polyclonal or monoclonal antibody which recognizes an epitope of a protein of 48,000 dalton, where the protein recognizes is a surface protein of a merozoite of Plasmodium falciparum which has a peptide of SEQ ID NO:1 or a sequence wherein SEQ ID NO:1 has been modified by insertion, deletion or substitution and the sequence inhibits the binding of inonoclonal antibody 245 to Plasmodium merozoites, as well as fragments of the antibody; the present invention relates to composition and kits containing the same, as well as methods of using the same;