Physicochemical characterization of human herpesvirus 6 infectivity

Infectivity of human herpesvirus 6 (HHV-6) was physicochemically characterized. Virus particles were excreted from infected cord blood mononuclear cells into the culture supernatant at a concentration of 10(8) to 10(9) virus particles/ml. The virus particle/infectivity ratio of HHV-6 in the culture supernatant was approximately 10(3):1 and that in the sonicated infected cells was 10(4):1. Infectivity was stable below 37 degrees C and at neutral pH (7.0 to 8.5). These fundamental data may be useful for serological and biological research on HHV-6.