Excerpt

The picornaviruses are small (22 to 30 nm) nonenveloped, single-stranded RNA viruses with cubic symmetry. The virus capsid is composed of 60 protein subunits, each consisting of four poly-peptides VP1–VP4. Because they contain no essential lipids, they are ether resistant. They replicate in the cytoplasm. The picornaviruses that affect humans are the enteroviruses, found primarily in the gut; the rhinoviruses, found in the upper respiratory tract and hepatovirus (Hepatitis A virus) in the intestine and liver. Subclinical infections with the picornaviruses are common. The hepatitis A virus is discussed in Chapter 70, “Hepatitis Viruses.”

Copyright © 1996, The University of Texas Medical Branch at Galveston