Methods for propagating fastidious human viruses and for producing purified suspensions thereof

A method to determine the infectivity of a sample of a fastidious human virus selected from the group consisting of human papillomavirus, varicella-zoster virus, cytomegalovirus, and gastroenteritis virus comprising the steps of:

• preparing serial dilutions of said sample;
• incubating each of said serial dilutions with pieces of human tissue known to be susceptible to said virus;
• placing each of said pieces of human tissue beneath the renal capsule of an immuno-compromised animal;
• allowing each of said pieces of human tissue to remain in said immuno-compromised animal for a period of time sufficient to produce an effect in said tissue that is caused by said virus when said virus infects said tissue;
• determining if said effect has been produced in each of said pieces;
• and
• determining the infectivity of said sample by determining which of said serial dilutions produced said effect in one half of the pieces of human tissue incubated with said dilution.

A method for testing a chemical or biological substance to determine its antiviral activity against a fastidious human virus selected from the group consisting of human papillomavirus, varicella-zoster virus, cytomegalovirus, and gastroenteritis virus comprising the steps of:

• infecting human tissue known to be susceptible to said fastidious human virus with said virus;
• placing said infected tissue beneath the renal capsule of an immuno-compromised animal;
• administering said substance to said animal;
• allowing said tissue to remain in said animal for a period of time sufficient to produce an effect in said tissue that is caused by said virus when said virus infects said tissue;
• and
• determining if said effect has been produced.