264 



PLASMODRTM, HAEMOPROTEUS AND LEUCOCYTOZOON 



Malaria is primarily a disease of 

 warmer climates nowadays, but at one 

 time it was common in the temperate zone. 

 Nevertheless, malaria is still the most 

 important human disease from a global 

 standpoint. Of the 1955 world population 

 of 2, 653 million, 1070 million lived in 

 malarious areas, and 696 million of these 

 were protected poorly or not at all from 

 malaria. In 1955 there were still 200 to 

 225 million cases of malaria in the world, 

 with more than 2 million deaths (Diehl, 

 1955). 



Malaria control has eliminated or al- 

 most eliminated malaria from many parts 

 of the world (Pampana and Russell, 1955; 

 Russell, 1956, 1958; Anonymous, 1956), 

 largely by use of residual spraying with 

 DDT and other insecticides. At the end 

 of World War II there were about 4 million 

 cases of malaria a year in southern Europe 

 from Spain to Bulgaria. In 1956 there 

 were less than 10,000 cases in the same 

 area. 



Malaria was one of the causes of the 

 decline of the Roman empire. The swampy 

 land of the Roman Campagna made it al- 

 most uninhabitable because of the disease. 

 There were 411, 602 cases of malaria in 

 Italy in 1945. Systematic spraying with 

 DDT was begun in 1946, and as a result 

 only 12 cases of indigenous malaria (both 

 primary cases and relapses) were reported 

 in 1953. In 1955 there were only 3. 



During World War I, the British and 

 French landed armies at Salonika, Greece, 

 with the objective of driving into Germany 

 thru the back door. Malaria wrecked 

 their plans and immobilized their armies. 

 There were 2 million cases of malaria in 

 Greece in 1942. In 1950 there were 

 50,000, and in 1952 only 408. 



In the Eastern Mediterranean coun- 

 tries, with a population of about 170 mil- 

 lion, there were about 40 million cases of 

 malaria a year in 1949. There are now 

 about 14 million, and it has been shown 

 that it is technically possible to eliminate 

 malaria from the area. 



Malaria has been completely elimina- 

 ted from Sardinia and Sicily, and it is 



practically gone from Venezuela, Brazil, 

 British Guiana, Argentina, Cyprus, Ceylon 

 and parts of India, to mention a few of the 

 places. 



In the United States there were a mil- 

 lion cases of malaria a year among a pop- 

 ulation of 25 million in 12 southern states 

 during 1912 to 1915. Before that, malaria 

 was an important disease thruout the mid- 

 west. Ackerknecht (1945) has given its 

 history in that region from 1760 to 1900. 

 The decrease of malaria in this country 

 was due only in small part to measures 

 aimed directly at the disease, but more to 

 agricultural development and to other, 

 still unknown, factors. It was almost en- 

 tirely eliminated from the midwest, for 

 instance, by farm land drainage. 



After World War II an intensive cam- 

 paign was started to wipe out malaria from 

 this country. Residual spraying of dwell- 

 ings, outhouses, barns, etc. was practiced 

 in malarious areas. Mosquito larval con- 

 trol measures were intensified. An attempt 

 was made to follow up every case diagnosed 

 as malaria, to get a blood smear in order 

 to be sure that it actually was malaria, and 

 to treat it immediately in order to prevent 

 it from being a source of further cases. 



During 1949 less than 5000 cases were 

 reported in the U. S. During 1955, 477 

 cases were reported. Of these, 64 were 

 appraised by the U. S. Public Health Serv- 

 ice, and only 29 were confirmed by blood 

 smear as malaria. Only 4 were primary 

 indigenous cases. Two were in California, 

 1 in Arizona, and the fourth--acquired by 

 blood transfusion--in Illinois. In 1957, 

 157 cases were reported, of which 138 

 were appraised by the Public Health Serv- 

 ice; 102 were confirmed, and 11 of these 

 were primary indigeiious cases (Dunn and 

 Brody, 1959). In 1958, 94 cases were re- 

 ported, of which 61 were confirmed. Seven 

 of these were primary indigenous cases, 4 

 of them resulting from blood transfusions, 

 and 1 natural case each originating in Cal- 

 ifornia, Arizona and possibly Pennsylvania 

 (Brody and Dunn, 1959). 



One outbreak of malaria illustrates 

 what can happen if conditions are right 

 (Brunetti, Fritz and Hollister, 1954). It 



