92 



development of the spirochaete. Several cases of direct transmission 

 from man to man have occurred under exceptional circumstances, 

 such as by contact with, and subsequent absorption of the virus from, 

 freshly shed infective blood, and the possibility of direct infection is 

 proved by experiments here described. 



Scott (J. W.). Experimental Transmission of Swamp Fever or 

 Infectious Anemia by means of Insects. — Jl. Amer. Vet. Med. 

 Assoc, Washington, D.C., ix, no. 5, February 1920, pp. 448-454. 



Feeding exj)eriments have shown that swamp fever is not transmitted 

 naturally by way of the ahmentary canal. Inoculation is possible 

 through scratches or cuts in the skin or by agents actually carrying 

 infected blood from one horse to another, such as is known to be true 

 of certain biting insects. 



Abrasions of the skin are, however, excluded as avenues of infection, 

 as they do not conform in incidence to the seasonal occurrence of 

 swamp fever. Lice, scab mites and ticks are ehminated on similar 

 grounds. The only other agents in Wyoming are mosquitos and 

 certain biting flies. 



Experiments with mosquitos gave negative results, but experiments 

 with Stomoxys calcitrans and Tabanus septentrionalis, so conducted 

 as to ehminate other possible sources of infection, showed that these 

 flies, and probably certain other biting flies, are capable of transmitting 

 the disease to horses. Consequently remedial methods should be on 

 the following lines. Cases of swamp fever should be killed or carefully 

 isolated, particularly in the season when flies are abundant, and the 

 bodies of horses that have died of the disease should be burned or 

 buried. Suspected horses should be carefully v/atched, but healthy 

 carriers probably afford the most important method of spreading the 

 disease. Their detection is very difficult. If detected, they should on 

 no account be moved from one place to another. AU movements of 

 horses from an infected area, during or some time after the infective 

 season, should be suspended. Horses introduced from such an area 

 should be isolated for at least three months and kept under observation 

 [see also R.A.E., B, vii, 165]. 



Herms (W. B.). What shall we do with ohf Information concerning 

 Malaria in California? — MtJilij. Bull. California State Bd. Health, 

 Sacramento, xv, no. 6, December 1919, pp. 181-189. [Received 

 22nd March 1920.] 



The control of malaria presents the chief rural sanitary problem in 

 California at the present time, although the malaria rate for the State 

 as a whole has been reduced by 60 per cent, in the last ten years.- 

 Irrigation need not involve malaria, if correct methods are employed, 

 including in particular adequate drainage. Rice culture in itself need 

 not increase malaria. [R.A.E., B, V; 142.] 



Though CaUfornia's death-rate from the disease (4-8 per 100,000) 

 seems low, the State should not be regarded as a whole to appreciate 

 the position. Thirteen counties (20,000 square miles) harbour 

 three-fifths of the malaria in the State and had in 1916 a death rate 



