172 



harmless to them, though repeated investigations have failed to reveal 

 them in the proboscis. Experimental infection with Stomoxys is 

 being tested. 



Russ (V.) and others. Studien iiber die Malaria in Niederosterreich, 



[Studies on Malaria in Lower Austria.] — Veroffentlichungen des 

 Volksgesundheitsamtes, Vienna, no. xiv, 1921, 39 pp. 



This publication comprises five sections, of which four are noticed 

 here. Of these the introductory notes, the section on the epidemiology 

 of malaria in Lower Austria, and the concluding notes, are by Dr. 

 Russ, whilst that dealing with the distribution of Anophelines is by 

 Dr. Franz Maidl. 



The fact that the collapse of the Austrian front occurred at the 

 end of October 1918, when the malaria season was ended, permitted 

 measures to be taken against an epidemic in 1919. These included 

 the formation of a Malaria Sanitary Column, which comprised a 

 medical and a zoological side. The latter carried out a system of 

 Anopheline surveys from May 1919 onwards, the method usually 

 followed being a search for larvae, adults being looked for in special 

 cases only. Both the species foimd in Lower Austria, A . maculipennis, 

 Mg. {claviger, F.) and A. bifurcahis, L., are recognised carriers of 

 malaria. 



A long list of infested localities is given. Definite Anopheline areas 

 are the plains, such as the Vienna basin and the Danube valley. From 

 these the mosquitos appear to have penetrated into the valleys of the 

 smaller rivers and streams, and their distribution is practically universal, 

 occurring wherever conditions are favourable. In several localities 

 A. maculipennis and A. bifurcatus occurred together, with a general 

 predominance of the former. Neither the plains nor the mountain 

 valleys appear to favour either of them specially. Larvae were found 

 in both stagnant and running water, as well as in waters that were 

 both clean and foul. 



They were less abundant away from villages and in uninhabited 

 situations, probably owing to the lack of winter shelters. The adults 

 are chiefly found in privies and in the shelters of domestic animals 

 of all kinds, though cattle sheds adjoining horses' stables appear to 

 be preferred to the. latter. The date of appearance of the larvae 

 depends principally on the temperature of the water. Floods and 

 high water-levels destroy the larvae, and drought, involving the dis- 

 appearance of breeding places, has a like result. In spring and summer 

 larvae of various sizes occur together, and this explains why there 

 is no distinct periodicity in the abundance of larvae and adults. 



The epidemiological observations that were made lead to the con- 

 clusion that malaria in Lower Austria is not an exotic disease, but 

 is even now one of long standing and somewhat rare occurrence. 



As malaria carriers (chiefly from Italy and Albania, and nearly all 

 cases of benign tertian or of a mixed infection of benign and malignant 

 tertian — quartan being very rare) and Anophelines are abundant 

 in Lower Austria, the absence of epidemics in 1919 and 1920 point 

 to the absence of a third factor needed to complete the chain. This 

 appears to be the climate, which seems to prevent either the union 

 of the gametes or their development subsequent to union. Dr. Russ 

 inclines to the opinion that this climatic factor was not peculiar to 

 1919 and 1920, but that the mean summer temperature is normally 

 too cold. 



