The Course of the Blood-Induced Plasmodium berghei Infection in White Mice

Abstract

There is a prepatent period of 3-6 days, avg. 3.98 [plus or minus] 0.12; a patent period of 4-19 days, avg. 10.34 [plus or minus] 0.43; a peak parasitemia at 5-13 days, avg. 8.38 [plus or minus] 0.40. Death, in most cases, occurs 24 hours after the peak; mortality rate is 100%. On the 2d day of patency the number of merozoites per segmenter ranged from 3 to 16, avg. 8.04 [plus or minus] 0.35; during the terminal stage of the infection the range was 12-14 merozoites per segmenter, avg. 12.8 [plus or minus] 0.49. The normal red cell count of 9.82 million per cu. mm. dropped to 1.17 million per cu. mm. shortly before death. Physical signs of the infection were ruffling of the fur, loss of the normal pink color of the eyes, ears, and extremities, loss of weight, and inactivity. These signs were intensified at the terminal stage of the disease when they were accompanied by labored breathing and somnolency.