An outbreak of Plasmodium inui malaria in a colony of diabetic rhesus monkeys.

: Plasmodium inui malaria is an infrequently reported disease of Macaca mulatta. In this report a total of 21 of 48 monkeys in a closed colony of diabetic animals developed hematological evidence of P. inui infection with five showing overt clinical signs of the disease. Diagnosis was confirmed morphologically, serologically and by transmission studies. Since six of these animals were born in the colony, a means of transmission was sought and it was determined that multiple use of a syringe to administer intravenous anesthesia was the probable means of cross transmission.