Eastern equine encephalitis causes, Eastern equine encephalitis is caused by what the cause

Eastern equine encephalitis is caused by what the?

(a) causes Eastern equine encephalitis is a

arbovirus group A, the strains of representative strains of Ten Broeck, in the electron microscope, virus particles are spherical RNA viruses, enveloped with a diameter of 40 ~ 60nm, the ether, formaldehyde, UV, oxygen sodium cholate sensitive to trypsin is not sensitive to aggregation 1 day old chicks and adult goose red blood cells, 60 ℃ 10min heating can be inactivated, -70 ℃ to long-term preservation of the virus in pH5.1 ~ 5.7 unstable, the virus In the chick embryo, hamster kidney, guinea pig kidney, monkey kidney, kidney, duck under the group results to develop a good reproduction of the experimental animals such as mice, guinea pigs, chickens have a strong invasion and virulence, intracerebral inoculation and subcutaneous inoculation enables many birds and rodents disease, some birds, rodents, livestock, poultry can be infected.

other in some areas of Central America and South America there is a type of Eastern equine encephalitis virus variants, its antigenicity and Ten Broeck strains were significantly different, the strains in horses can cause acute neurological disease, and rarely cause human disease.

(B) the pathogenesis

arthropod bites an infected, the virus in the local tissue and lymph node replication, viremia continued to depend on the occurrence of local tissue outside the nervous system within the stage of viral replication, monocyte - macrophage system to clear virus speed and the appearance of specific antibodies and therefore quite different clinical manifestations.

the naked eye can see large hyperemia water species, and a wide range of nerve cell degeneration, there are multiple brain hemorrhage, microscopic examination showed neuronal degeneration and necrosis, perivascular lymphocytes, monocytes and polymorphonuclear leukocyte infiltration to form a "set around the vessels," and some glial cell proliferation and accumulation of polymorphonuclear leukocytes in the formation of nodules, lesions were mainly seen in the brain basal ganglia, brain stem gray matter and white matter, cerebellum and spinal cord can also be violated.