The abnormal life span of the red blood cell.

Abstract

IN THE PATIENTS infected by simian malaria, anemia was quite mild. The greatest fall in hematocrit level was about 10 points and in most it was no more than 5 hematocrit units. At the same time, most volunteers developed mild reticulocytosis. Those who received Plasmodium vivax had a much more pronounced anemia. The hematocrit level fell to 25, at which time it was necessary to institute therapy; reticulocytosis did not occur until after treatment had been started. We measured the red-blood-cell survival rates for several of these patients, using the Cr 51 technique 1 and labeling cells at the time of onset of the fever. In one patient, however, we labeled the cells 2 days after they were infected by the mosquito. The cell-survival rates of three patients infected with P cynomolgi are shown in the Figure. The shortening of the life span of the red blood cell is