约氏疟原虫对小鼠具有高度的感染力,每鼠接种5个感染疟原虫的红细胞时,66.6％的小鼠出现原虫血症。伯氏疟原虫的接种剂量如低于1×10~6个感染疟原虫的红细胞,只能使部分小鼠出现原虫血症。两种鼠症原虫用相同剂量接种小鼠后,原虫血症的出现时间前者早于后者。接种约氏疟原虫的阳性小鼠能自然转阴,不引起小鼠死亡;但接种伯氏疟原虫后的阳性小鼠则不能自然转阴。 Plasmodium yoelii has a high infectivity in mice, and parasitemia occurs in 66.6% of mice when inoculated with 5 erythrocytes infected with Plasmodium. Plasmodium berghei vaccination doses of less than 1 × 10 6 infected red blood cells of Plasmodium, only some of the mice parasitemia. After the mice were inoculated with the same dose of the two murine protozoa, the former was earlier than the latter. The positive mice vaccinated with P. yoelii naturally turned negative without causing the mice to die; however, the positive mice after inoculation with P. berghei did not spontaneously turn negative.