a sequence of at least ten nucleotides of nucleic acid from p ovale and 2 comparing the ability of the probe to detect all the plasmodium species in a hybridization assay probes that hybridize to p ovale more favorably than to other three species are included in the invention p falciaprum p vivax p malariae and p ovale nucleic acid may be obtained from biological samples such as whole blood bone marrow csf from infected individuals using standard nucleic acid isolation methods in the art p falciaprum as well as p vivax p malariae and p ovale can also be obtained from culture for example dna encoding plasmodium ribosomal rna may be obtained by pcr amplification of dna prepared from a whole blood sample of an infected patient using the methods and primers described herein and known in the art any plasmodium sequence e g a sequence encoding 58 5 8s 18s or 28s ribosomal rna may be selected as a candidate sequence for the identification of probes preferred sequences are those that diverge from analogous sequences in non human plasmodium or other protozoan parasites like for example babesia or thileria as determined by phylogenetic comparison the nucleic acid probes of the invention are at least 10 nucleotides in length and may contain deoxyribonucleotides dna probes ribonucleotides rna probes peptide nucleic acid pna probes or combinations or modifications thereof the probes may be single stranded or double stranded and may be prepared by any of a number of standard methods in the art for example the probes may be made by chemical synthesis restriction endonuclease digestion of a vector e g a plasmid containing a sequence corresponding to the probe polymerase chain.