Herpes simplex virus (HSV) is the prototype of a family of large, enveloped, double‐stranded
DNA viruses, the Herpesviridae, which cause significant morbidity and mortality in humans.
Productive replication of HSV in cells in culture results in definitive changes in cellular
physiology and metabolism, ultimately leading to lysis. These definitive aspects of viral‐host
interactions enable diagnosis of HSV infections. In this unit, a series of methods are
described for the propagation, quantification, and storage of HSV. Infectious center assays …

Newcastle disease virus (NDV) is a prototype paramyxovirus used to define basic steps in
the life cycle of this family of viruses. NDV is also an ideal virus system for elucidating
determinants of viral pathogenicity. Some strains of this virus are important agricultural
pathogens that cause disease in poultry with a high mortality while other strains are avirulent
and used for vaccines. Methods for preparation and titration of virus stocks are essential for
all of these purposes. Procedures for growth and purification of NDV stocks in embryonated …