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Which diseases are caused by the varicella-zoster virus?
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infectious disease
Birds are the primary reservoirs of West Nile virus. The virus is transmitted to humans and horses by mosquitoes that have bitten infected birds.
The varicella-zoster virus (VZV) is the causative agent of two distinct clinical conditions:
- Chickenpox (varicella): This is the primary infection, typically occurring in childhood, characterized by an eruption of itchy, fluid-filled blisters across the body.12
- Herpes zoster (shingles): This condition results from the reactivation of the virus after it has remained latent in the body's sensory nerve ganglia for years or even decades following the initial chickenpox infection. It typically manifests as a painful, localized rash of blisters along a specific nerve pathway (dermatome).123
While a person with herpes zoster can transmit the virus to someone who has never had chickenpox or been vaccinated, that individual will develop chickenpox, not shingles. Vaccination is available to prevent both the primary infection and the reactivation of the virus in older adults and immunocompromised individuals.123