We have shown previously that in infected HEL cells varicella-zoster virus (VZV) causes a shift from polar to neutral lipid synthesis and that some strains of the virus depressed total lipid synthesis. In this report we show that VZV produces a similar effect on the lipid metabolism of infected human embryonic kidney cells. The pattern of lipid synthesis in human embryonic kidney cells infected with either of two strains of influenza type A virus was similar to that of control uninfected cells, whereas the greatest difference and the pattern closest to that seen with VZV was produced by influenza type B strains. These findings are discussed in light of the association of prior infections with influenza B virus and chickenpox and the subsequent development of Reye’s syndrom