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What is Subacute sclerosing panencephalitis virus (SSPE) is best described by which of the following statements? and explain in detail?
SSPE is a late and rare manifestation of measles. It is a progressive encephalitis involving both white and gray matter. Demyelination is seen only at an advanced stage of the disease in a few cases. In 1985, viral RNA was demonstrated in brain cells from a patient with SSPE by the use of in situ hybridization.