TRANSMISSION ELECTRON-MICROSCOPIC STUDY OF THE HEMORRHAGIC SPOTS IN PATIENTS WITH EPIDEMIC HEMORRHAGIC-FEVER IN THE EARLY-STAGE

Epidemic hemorrhagic fever (EHF) virus particles were found in the squ amous epithelial cells and the capillary endothelial cells of the pete chial spots located on the mucous membrane of the soft palate in 3 pat ients with severe early-stage EHF with transmission electron microscop y. The virus particles were round or oval in shape, about 100 nm in di ameter, with a two-layer lipid envelope from which spikes were protrud ing. The nucleocapsid of the virus appeared to be hollow microfilament oid or dense granules. Meanwhile, budding virus particles with a diame ter of 80 nm were found in the enlarged Golgi apparatus. The infected cells displayed an enlarged and proliferating Golgi apparatus. The mor phological characteristics of the viron mentioned above coincided with those of the virus particles of the family Bunyaviridae. This study i s the first to demonstrate that the squamous epithelial cells on the m ucous membrane of the soft palate are the target cells of EHF infectio n and to provide subcellular morphological evidence of petechial hemor rhage at the soft palate.