David A. Simpson

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In continuation of a series of studies of arboreal mosquitos as virus vectors in Uganda, 12 strains of Zika virus and one strain of another Group B arbovirus were isolated between November 1961 and June 1963 from pools of Aedes (Stegomyia) africanus caught on a 120-foot (36.5-m) tower in Zika forest. For five strains it is known at what height the mosquitos(More)
Eleven rhesus monkeys were monitored intensively during experimental infection with Ebola virus. Prominent neutrophilia with left shift and lymphopenia were the earliest abnormalities and were statistically significant by day 4 (P less than .02 and P less than .01, respectively). By day 4 falls in platelet counts were not statistically significant, whereas(More)
Patients with severe viral infections such as Lassa or Ebola may be denied adequate laboratory investigations because of justifiable fears among laboratory staff. This study in monkeys was designed to provide comprehensive haematological and biochemical monitoring in a contained environment during all stages of Ebola infection. Marked neutrophilia,(More)
Arbovirus infection and presence of haemagglutination-inhibiting antibodies in small mammals, birds and livestock were examined over a period of five years on the Kano Plain in western Kenya. Eleven isolations were made from mammals and birds. The viruses were identified as Arumowot and Germiston while three different agents could not be shown to be related(More)
Experimental infection of rhesus and vervet monkeys with Ebola virus produced a uniformly fatal illness. The course of the disease resembled that found in man with weight loss, anorexia, fever, haemorrhages and skin rash being frequently seen. Viraemia was obvious within two days of infection and persisted until death which occurred between days five and(More)