Cytopathic changes in LLC-MK2 cells infected with SV4 virus, observed with the electron microscope and using acridine orange staining and fluorescent microscopy, have been shown to be similar to that caused by picornaviruses and members of the Columbia-SK virus group. The virus was found to be stabilized against heat in the presence of molar magnesium chloride, and to be stable at pH 3.5. The virus was non-pathogenic for suckling mice, failed to agglutinate sheep and human "O" red blood cells, but agglutinated rhesus monkey erythrocytes at 4 °C. On the basis of these properties and those already known, it was suggested that SV4 virus be placed in the group Enteroviruses of lower animals.
Evaluation of the Direct Acridine Orange Staining Method for Diagnosis of Malaria
