SOME ECOLOGICAL ASPECTS OF THE PROBLEM OF ARTHROPOD-BORNE ANIMAL VIRUSES IN THE WESTERN PACIFIC AND SOUTH-EAST ASIA REGIONS.

In recent years there has been an increasing awareness of the importance of arthropod-borne viruses in the Western Pacific region and in South-East Asia. This realization of the importance of these viruses as causes of human morbidity and mortality and of economic loss due to infection of domestic animals has led to studies attempting to elucidate the basic ecology of some of these viruses. The author reviews the extent of knowledge of the ecology of Japanese and Murray Valley encephalitis viruses and indicates possible mechanisms for the overwintering of the viruses based on experiments in which other viruses were mainly used. He discusses the limited available knowledge on the ecology of dengue and emphasizes the necessity of research on the possibility that this disease is a zoonosis. A brief discussion is also given of the haemorrhagic diseases which are found in these regions and a brief description of the state of knowledge on the ecology of Kyasanur Forest disease and epidemic nephroso-nephritis. A brief discussion is also included on the ecology of the tick-borne Russian spring-summer encephalitis.