[Studies on diagnosis of falciparum malaria based on amplifying specific SSUrDNA fragment with nested PCR].

Two pairs of primers specific to small subunit ribosomal DNA of Plasmodium falciparum were designed and the expected SSUrDNA fragment was amplified for detecting P. falciparum infection with double-temperature-nested polymerase chain reaction using DNA prepared by boiling method. The results showed that the nested PCR could amplify a constant size of desired SSUrDNA fragment of P. falciparum which was further confirmed by digestion of restriction endonuclease and could detect parasitemia level of 0.8 x 10(-6). It has great potentials for identifying Plasmodium species in ring form of erythrocytic stage and detecting mixed Plasmodium infections. Therefore, it is suggested that this method is sensitive, accurate, simple and rapid in detecting Plasmodium falciparum in blood samples for malaria diagnosis.