Type of virus: double-stranded DNA virus; herpesvirus
Transmission: respiratory route
Reservoir: humans
Pathogenicity: incubation approximately 2 weeks; relatively mild childhood disease; more than 2 million cases occur each year in the US of which the CDC reports there are only 100 deaths from encephalitis or viral pneumonia. Primary infection - repiratory tract to skin cells; vessicles form the last 3 to 4 days and then scab over; lesions usually confined to face, throat, and back, but may also be found on the chest and shoulders.
Treatment: vaccine marketed in 1995; active attenuated vaccine; must be administered before 12-13 years of age; immunity may last 5 to 10 years; booster may be required.
Other: occasional severe complications due to Reye's Syndrome but the death rate is now down to less than 30%; more severe infection develops in adults with a significant mortality rate.
* After infection, the virus remains latent in the body after entering peripheral nerves and moving to the dorsal root ganglion near the spine. It persists there indefinitely as viral DNA. If reactivated, the virus moves along the peripheral nerves to the cutaneous sensory nerves of the skin to cause a secondary infection called shingles. Burning rash develops normally in the waist area but may also appear on the face, chest and back. Exposure to shingles can cause a chicken pox infection to develop.
LINKS
