On the Study of Encephalitis Virus isolated from Naturally Infected Chicken.

During the epidemics of B type encephalitis in 1954 and 1955 in Fukien,epizootic simulta- neously occurred among chicken causing the loss of several hundred heads.From seven dead or dying birds,three strains of encephalitis virus were isolated from chicken brains,and identified to be B type encephalitis by the following tests:Hemagglutination test of a great variety of red blood cells; hemagglutination inhibition tests with serum prepared with Yakanawa strain;range of animal patho- genicity;cross neutralization and complement fixation tests with known B type encephalitis virus; and,finally,cross protection test in white mice.All the tests clearly indicated that the viruses isolated were not New Castles Disease virus,but B type encephalitis indistinquishable from those isolated from human cases in the same localities. Attempt was made to isolate the virus from Lashiohelea taiwana captured from the chicken crops.However,probably owing to the early season,no positive results were obtained.But the possibility of chicken as a source of infection of B type encephalitis virus must now be consi- dered in the control of this disease.