1.White neurosyphilitic patients were infected with foreign Plasmodium vivax malaria, both by blood inoculation and by mosquito bite. Infections resulting from mosquito transmission showed the averaged prepatent period to be 12.8 days and the average incubation period to be 14.2 days. These periods were significantly shorter for the Mediterranean strains than for strains from the Pacific.
2.In the mosquito transmitted infections, the first maximum fever usually preceded the maximum parasitemia by several days. The average of the first maximum fever was 106.0° F. The maximum parasitemia averaged 13,900 parasites per cmm.
3.In the blood transmitted infections, the first maximum fevers and the maximum parasitemias usually occurred at about the same time. The maximum parasitemias were higher than in mosquito induced infections.
4.The tertian type paroxysms showed an average periodicity of 44.5 hours, ranging from 43.6 to 45.1 hours. None showed a 48-hour periodicity.
5.Chills accompanied the fevers in 73.2 per cent of the cases. Chills were less frequently present with the first 5 fevers than with the later fevers.
6.The types of fever at onset of mosquito induced infections were: quotidian, 50 per cent; remittent, 42 per cent; and tertian, 8 per cent. These types were often succeeded by a different type.
7.Sodium bismuth thioglycollate was reliable in changing remittent and quotidian paroxysms to tertian occurrence.
8.Usually, the primary infections produced over 10 paroxysms.
9.Little or no heterologous immunity was demonstrated between 5 foreign strains and the St. Elizabeth strain of P. vivax.
10.The foreign malarias appear to be satisfactory as a therapeutic agent to treat white neurosyphilitic patients. This was not true of Negro patients.
Now Assistant Dean, Emory University Medical School.