Estimation of the potential ability of nanoparticles (NP) to affect human health has generated a need for developing rapid, sensitive, and efficient laboratory tests of the toxicity of nanomaterials. The purpose of the investigation was to study the cytotoxic effect of NP of silver (Ag) and silicon dioxide (SiO2). The transplantable Vero cells treated with NP at different concentrations were used as target cells. Some experiments examined the combined effects of nanopowders and herpes simplex virus type 2 (HSV-2) on Vero cell viability and the direct effect of NP on the reproductive potential of HSV-2 in the culture. SiO2 NPs at concentrations of 1.0 to 0.1 mg/ml were found to cause a marked cytotoxic effect that was in the complete destruction of the cell monolayer. Ag HPs were more toxic than silicon nanopowders and induced a complete degradation of the cell monolayer at substantially lower concentrations. The results of the study formed the basis for the development of a rapid (24-48-hour), reliable, and efficient test for the toxicity of nanomaterials, by using the cultured cells in the laboratory setting. It was also shown that silicon NPs did not noticeably affect the reproductive potential of HSV-2 while nano silver suppressed the capacity of HSV-2 for multiplication, by significantly reducing viral progeny titer in the cell culture.