Michael N. Oxman, MD
Herpes Simplex Viruses and Varicella-Zoster Virus
June 1, 2011
Herpes Simplex Virus and Varicella-Zoster Virus
Michael N. Oxman, MD in collaboration with Bridget A. Quinn
Herpes Simplex Virus (HSV) and Varicella-Zoster Virus
Key Features of the Human Herpesviridae (HSV-1, HSV-2, VZV, CMV, EBV, HHV-6,-7,-8)
Herpesviruses are large and complex viruses.
Herpesviruses encode many enzymes, including enzymes involved with nucleic acid synthesis and nucleic
This is important because these viral enzymes are potential targets for antiviral drugs like
Members of Herpesviridae all have a similar virion structure:
(Remember, enveloped viruses acquire their lipid membrane from the host
Between the envelope and the capsid is an amorphous protein-filled region called the
linear double stranded DNA genomes
genomes consist of UL and US regions bounded by inverted repeats (IR)
However, the exact arrangement of the genome differs in different Herpesviruses.
Virus replication and assembly occurs in the nucleus of the infected cell,
although late steps in virion
assembly may take place in the cytoplasm.
There are no common Human Herpesvirus Family antigens
All members of the Herpesviridae
can establish latency
in their natural host.
Members of the Herpesvirus Family are subdivided into subfamilies, primarily on the basis of their biologic properties
and/or their genome organization and DNA sequence homology.
(HSV-1, HSV-2, VZV) have a relatively broad host range; a short replication
cycle; produce CPE in cell cultures and in vivo that is characterized by eosinophilic intranuclear inclusion
bodies, multinucleated giant cells, and subsequent cell death; and establish latent infections, primarily in
(CMV, Roseolaviruses [HHV-6, HHV-7]) have a relatively restricted host range, a
long replication cycle, produce slowly progressive infections in cell culture, and produce CPE characterized
by cell enlargement (cytomegalia). Persistent or latent infections are readily established in secretory glands,
in reticuloendothelial cells, in the kidney and in other tissues.
(EBV, HHV-8) have a very restricted host range.
They replicate in
and tend to be specific for either T- or B-lymphocytes, in which they may either
establish a latent or a productive lytic infection.
Latency is frequently demonstrated in lymphoid tissue.
EM of a Herpesvirus
Key Features of the Alpha (
(HSV and VZV)
The double stranded DNA genome of the alpha
herpesviruses have the following arrangements:
Alpha Herpesvirus Genomes