From the Guidelines
Herpes zoster and varicella zoster are not the same, although they are caused by the reactivation of the same virus, varicella zoster virus (VZV). Herpes zoster, also known as shingles, is a condition that occurs when the VZV, which remains dormant in the dorsal root ganglia or sensory ganglia of the cranial nerve after a primary varicella infection or chickenpox, reactivates [ 1 ]. This reactivation typically occurs in adults or the elderly when the cellular immune response fails to control the latent replication of VZV.
Key Differences
- Varicella zoster virus (VZV) causes both chickenpox (varicella) and shingles (herpes zoster)
- Chickenpox (varicella) is the primary infection, usually occurring during childhood
- Herpes zoster (shingles) is the reactivation of the dormant virus, typically occurring in adults or the elderly
- Herpes zoster manifests as a painful, vesicular, cutaneous eruption with a dermatomal distribution and can lead to potentially debilitating complications [ 1 ]
Prevention and Complications
The most effective strategy to prevent varicella, herpes zoster, and its related complications is by vaccination [ 1 ]. Herpes zoster can lead to complications such as postherpetic neuralgia (PHN), HZ ophthalmicus, bacterial superinfections, cranial and peripheral nerve palsies, and visceral involvement.
Clinical Considerations
In clinical practice, it is essential to distinguish between varicella and herpes zoster, as the management and treatment of these conditions differ. Vaccination is a crucial preventive measure, especially for adults and the elderly, to reduce the risk of herpes zoster and its complications [ 1 ].
From the Research
Definition and Relationship
- Herpes zoster, commonly referred to as "shingles," is caused by the reactivation of the varicella-zoster virus, which is the same virus that causes chickenpox (varicella) 2, 3, 4, 5, 6.
- The varicella-zoster virus remains dormant in the spinal and cranial sensory ganglia after the primary varicella infection, usually during childhood, and can reactivate later in life to cause herpes zoster 2, 4, 5.
Clinical Manifestations
- Herpes zoster typically presents with a vesicular rash and pain, usually in a dermatomal distribution, and can be accompanied by other symptoms such as malaise, headache, and low-grade fever 3, 6.
- Postherpetic neuralgia (PHN) is a common complication of herpes zoster, characterized by persistent pain in the affected area, which can last for months or even years after the rash has resolved 2, 3, 4, 5.
Management and Prevention
- Herpes zoster can be treated with antiviral medications such as acyclovir, valacyclovir, or famciclovir, which are most effective when started within 72 hours of the onset of the rash 2, 3, 6.
- Vaccination against varicella-zoster virus is available and can help prevent herpes zoster and PHN, especially in older adults 3, 5, 6.
- Two types of vaccines are available: a live attenuated VZV vaccine and a recombinant adjuvanted VZV glycoprotein E subunit vaccine, which can be used in severely immunosuppressed patients 6.