Varicella-Zoster Virus infections - chicken pox, herpes zoster

• What are neurotropic viruses? Do they all have envelope?
• What are some other viruses that invade the nervous system? Which of these are peripheral like VZV?
• What happens when Herpes Zoster is in the central nervous system?
• What happens when geniculate ganglion is affected by VZV?

Herpesviridae

8 infect humans in this family.

1. HSV 1
2. HSV 2
3. VZV
4. EBV
5. Cytomegalovirus
6. HHV 6
7. HHV 7
8. Kaposi’s sarcoma associated herpes virus

Chicken Pox

Herpes Zoster

Images

• on S1 dermatome
• T11-T12 with pseudohernia

VZV encephalitis

Confused with Herpes Viral encephalitis (by HSV1) and therefore less studied.

Ophthalmic Zoster

Trigeminal nerve (V) - opthalmic branch

Hutchinson’s sign

Because the nasociliary branch of the trigeminal nerve innervates both the cornea and the lateral dorsum of the nose as well as the tip of the nose.

There is a Hutchinson’s nail sign (Subungal melanoma) and a Hutchinson’s triad (congenital syphilis)

Ramsay Hunt Syndrome