Changes in Hematologic Values During Infection of New World Monkeys With Plasmodium falciparum and P. vivax.

Owl (Aotus sp.) and squirrel (Saimiri sp.) monkeys are used frequently in malaria vaccine trials, during which the animals are monitored daily for parasitemia and general well-being. Every 2 weeks, blood samples are taken, and hematology and chemistries are performed. We examined 97 cases of malarial infection in owl and squirrel monkeys, whose parasitemia increased by. 22,000 parasites/uL daily during a 14-day interval. After malaria challenge, unprotected animals had significant changes in hematologic values. These changes could not be completely attributed to the increase in the parasite counts.