Field and Laboratory Studies on Equine Encephalitis

THE epidemiologic and clinical features of human infections with the virus of eastern equine encephalomyelitis in Massachusetts have been described recently by Feemster.1 2 3 The present paper will discuss the research activities that have been carried on in the State since 1938 to throw light upon the possible reservoir hosts and vectors of the disease. At the time of the outbreak in horses and human beings in 1938 the only known laboratory vectors of the equine viruses were eight species of mosquitoes belonging to the aedes genus. Most of the laboratory experiments had been carried on with the western virus, but . . .