Medscape is available in 5 Language Editions – Choose your Edition here.


Varicella-Zoster Virus

  • Author: Wayne E Anderson, DO, FAHS, FAAN; Chief Editor: Michael Stuart Bronze, MD  more...
Updated: Oct 22, 2015

Practice Essentials

Varicella-zoster virus (VZV) causes chickenpox and herpes zoster (shingles). Chickenpox follows initial exposure to the virus and is typically a relatively mild, self-limited childhood illness with a characteristic exanthem, but can become disseminated in immunocompromised children. Reactivation of the dormant virus results in the characteristic painful dermatomal rash of herpes zoster, which is often followed by pain in the distribution of the rash (postherpetic neuralgia). See the image below.

Typical zoster in the vicinity of right popliteal Typical zoster in the vicinity of right popliteal fossa in a vertebral nerve L4 distribution.

Signs and symptoms

Pain and paresthesia are typically the first symptoms of VZV infection. Until the characteristic vesicular rash erupts, diagnosis may be difficult. A prodromal period during which symptoms may vary is common. Pain occurs in 41% of patients, itching in 27%, and paresthesias in 12%.

During the acute illness, patients may experience the following:

  • Pain (90%)
  • Helplessness and depression (20%)
  • Flulike symptoms (12%)

Herpes zoster (shingles)

  • The most common presentation is the shingles vesicular rash, which most commonly affects a thoracic dermatome
  • After a prodromal illness of pain and paresthesias, erythematous macules and papules develop and progress to vesicles within 24 hours
  • The vesicles eventually crust and resolve
  • Pain and sensory loss are the usual symptoms
  • Motor weakness also occurs and is frequently missed on examination
  • Cases of actual monoplegia due to VZV brachial plexus neuritis have been reported

Zoster multiplex

  • Shingles may appear in multiple dermatomes, both contiguous and noncontiguous, on either side of the body
  • Immunocompromised individuals are more susceptible
  • Terminology depends on the number of involved dermatomes and on whether the condition is unilateral or bilateral (eg, zoster duplex unilateralis refers to the involvement of 2 unilateral dermatomes)
  • Cases of zoster simultaneously occurring in 7 noncontiguous dermatomes have been reported

Zoster sine herpete

VZV infection may reactivate without causing cutaneous vesicles. These patients have severe dermatomal pain, possible motor weakness and possible hypesthesia, but no visible rash or vesicles.

VZV infection may present as acute peripheral facial palsy in 8-25% of patients who have no cutaneous vesicles. This is more common in immunosuppressed patients who use acyclovir (or other agents) as zoster prophylaxis.[1]

Central nervous system deficits

  • More common in immunocompromised individuals, but do occur in the general population
  • CNS involvement may become apparent 3 weeks after the onset of the initial rash
  • The manifestations are usually bilateral
  • The physical findings may progress
  • The underlying pathology typically progresses for 3 or more weeks
  • Progression for 6 months in immunocompromised individuals has been reported
  • Recurrence is rare but has been reported
  • Zoster encephalitis is also rare but is reported in otherwise healthy individuals

Ramsay-Hunt syndrome

This syndrome occurs when the geniculate ganglion is involved. The clinical presentation includes the following:

  • A peripheral facial palsy
  • Pain in the ear and face
  • Vesicles in the external ear canal (not always present)
  • Additional auditory and vestibular symptoms in some cases

Keratitis (herpes ophthalmicus)

  • Caused by reactivation of VZV infection in the ophthalmic division of the trigeminal nerve.
  • The presentation may include conjunctivitis or corneal ulcers
  • Complications include blindness
  • Vesicles do not have to be present
  • Rarely, the virus migrates along the intracranial branches of the trigeminal nerve, causing thrombotic cerebrovasculopathy with severe headache and hemiplegia

See Clinical Presentation for more detail.


When the presentation includes the typical dermatomal rash, additional studies are not required. Studies to consider in specific situations include the following:

  • If the diagnosis is in doubt, a Tzanck smear or culture of vesicular fluid can be performed
  • In cases of zoster sine herpete, DNA analysis via PCR can be used
  • In cases of acyclovir-resistant VZV, detections of mutations in thymidine kinase can be determined by PCR and sequence analysis
  • MRI may be useful if myelitis or encephalitis is suspected
  • Lumbar puncture may be helpful if signs suggest myelitis or encephalitis

See Workup for more detail.


Treatment options are based on the following:

  • Patient age
  • Patient immune state
  • Duration of symptoms
  • Presentation

Antiviral medications decrease the duration of symptoms and the likelihood of postherpetic neuralgia, especially when initiated within 2 days of the onset of rash. Oral acyclovir may be prescribed in otherwise healthy patients who have typical cases. Compared with oral acyclovir, other medications (eg, valacyclovir, penciclovir, famciclovir) may decrease the duration of the patient's pain.

Varicella zoster immune globulin (VariZIG) is indicated for administration to high-risk individuals within 10 days (ideally within 4 days) of chickenpox (VZV) exposure.[2] High- risk groups include the following:

  • Immunocompromised children and adults
  • Newborns of mothers with varicella shortly before or after delivery
  • Premature infants
  • Infants less than younger than 1 year of age
  • Adults without evidence of immunity
  • Pregnant women

See Treatment and Medication for more detail.



Varicella-zoster virus (VZV) is the cause of chickenpox and herpes zoster (also called shingles). Chickenpox follows initial exposure to the virus and is typically a relatively mild, self-limited childhood illness with a characteristic exanthem.

Approximately 1 per 4000 children develops VZV encephalitis, an acute neurologic disorder with potentially severe complications. In addition, immunocompromised children (eg, those receiving chemotherapy for leukemia or those with advanced HIV infection) can develop disseminated VZV infection, a potentially fatal complication.

After primary infection, VZV remains dormant in sensory nerve roots for life. Upon reactivation, the virus migrates down the sensory nerve to the skin, causing the characteristic painful dermatomal rash. After resolution, many individuals continue to experience pain in the distribution of the rash (postherpetic neuralgia). In addition, reactivation of VZV infection can cause a spectrum of atypical presentations, ranging from self-limited radicular pain without rash to spinal cord disease with weakness.



The host immunologic mechanisms suppress replication of the virus. Reactivation can occur if host immune mechanisms are compromised. This may be caused by medications, illness, malnutrition, or by the natural decline in immune function with aging. Upon reactivation, the virus migrates along sensory nerves and produces sensory loss, pain, and other neurologic complications. If motor nerve roots are also involved, weakness can develop in addition to sensory changes. Leptomeningeal involvement is rare but may develop when the ophthalmic branch of the trigeminal nerve is involved.



United States

The rate of occurrence is about 5 persons per 1000 population. Immunosuppression increases this risk. The risk of postherpetic neuralgia increases with age. Approximately 50% of patients older than 60 years may have temporary or prolonged pain syndrome.

The frequency of VZV infection may decrease as the immunized children become adults.


VZV infection occurs with the same frequency in the United States and internationally.



Severe pain and insomnia are most bothersome to patients. About 95% of patients with zoster experience severe pain during the illness.

Other presentations of zoster, including ocular (keratitis) and spinal cord (myelitis) presentations, may result in additional morbidity.

Bacterial superinfection (impetiginization) of vesicular skin lesions can occur.


The vesicular eruption of VZV infection may be more difficult to diagnose in patients with darker skin.


VZV infection occurs with equal frequency in males and females.


After primary infection, zoster can occur at any age. However, the risk of zoster increases with age.

The risk of postherpetic neuralgia also increases with advancing age.

Contributor Information and Disclosures

Wayne E Anderson, DO, FAHS, FAAN Assistant Professor of Internal Medicine/Neurology, College of Osteopathic Medicine of the Pacific Western University of Health Sciences; Clinical Faculty in Family Medicine, Touro University College of Osteopathic Medicine; Clinical Instructor, Departments of Neurology and Pain Management, California Pacific Medical Center

Wayne E Anderson, DO, FAHS, FAAN is a member of the following medical societies: California Medical Association, American Headache Society, San Francisco Medical Society, San Francisco Medical Society, International Headache Society, California Neurology Society, San Francisco Neurological Society, American Academy of Neurology, California Medical Association

Disclosure: Received honoraria from Teva for speaking and teaching; Received grant/research funds from Allergan for other; Received honoraria from Insys for speaking and teaching; Received honoraria from DepoMed for speaking and teaching.

Specialty Editor Board

Francisco Talavera, PharmD, PhD Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Received salary from Medscape for employment. for: Medscape.

Gordon L Woods, MD Consulting Staff, Department of Internal Medicine, University Medical Center

Gordon L Woods, MD is a member of the following medical societies: Society of General Internal Medicine

Disclosure: Nothing to disclose.

Chief Editor

Michael Stuart Bronze, MD David Ross Boyd Professor and Chairman, Department of Medicine, Stewart G Wolf Endowed Chair in Internal Medicine, Department of Medicine, University of Oklahoma Health Science Center; Master of the American College of Physicians; Fellow, Infectious Diseases Society of America

Michael Stuart Bronze, MD is a member of the following medical societies: Alpha Omega Alpha, American Medical Association, Oklahoma State Medical Association, Southern Society for Clinical Investigation, Association of Professors of Medicine, American College of Physicians, Infectious Diseases Society of America

Disclosure: Nothing to disclose.

Additional Contributors

Maria D Mileno, MD Associate Professor of Medicine, Division of Infectious Diseases, The Warren Alpert Medical School of Brown University

Maria D Mileno, MD is a member of the following medical societies: Alpha Omega Alpha, American College of Physicians, American Society of Tropical Medicine and Hygiene, Infectious Diseases Society of America, International Society of Travel Medicine, Sigma Xi

Disclosure: Nothing to disclose.


The authors and editors of Medscape Reference gratefully acknowledge the contributions of prior coauthor Amar Safdar, MD, to the development and writing of this article.

  1. Furuta Y, Fukuda S, Suzuki S, et al. Detection of varicella-zoster virus DNA in patients with acute peripheral facial palsy by the polymerase chain reaction, and its use for early diagnosis of zoster sine herpete. J Med Virol. 1997 Jul. 52(3):316-9. [Medline].

  2. Centers for Disease Control and Prevention (CDC. Updated recommendations for use of VariZIG – United States, 2013. Available at Accessed: July 23, 2013.

  3. Shapiro ED, Vazquez M, Esposito D, Holabird N, Steinberg SP, Dziura J, et al. Effectiveness of 2 doses of varicella vaccine in children. J Infect Dis. 2011 Feb 1. 203(3):312-5. [Medline].

  4. Pahud BA, Glaser CA, Dekker CL, Arvin AM, Schmid DS. Varicella zoster disease of the central nervous system: epidemiological, clinical, and laboratory features 10 years after the introduction of the varicella vaccine. J Infect Dis. 2011 Feb 1. 203(3):316-23. [Medline].

  5. Brink AA, van Gelder M, Wolffs PF, Bruggeman CA, van Loo IH. Compartmentalization of acyclovir-resistant varicella zoster virus: implications for sampling in molecular diagnostics. Clin Infect Dis. 2011 Apr 15. 52(8):982-7. [Medline].

  6. Kubeyinje EP. Cost-benefit of oral acyclovir in the treatment of herpes zoster. Int J Dermatol. 1997 Jun. 36(6):457-9. [Medline].

  7. Ready T. Varicella-Zoster Virus Globulin: New CDC Recommendations. Medscape Medical News. Available at Accessed: July 30, 2013.

  8. Updated Recommendations for Use of VariZIG - United States, 2013. MMWR Morb Mortal Wkly Rep. 2013 Jul 19. 62(28):574-6. [Medline].

  9. Dworkin RH, Barbano RL, Tyring SK, Betts RF, McDermott MP, Pennella-Vaughan J, et al. A randomized, placebo-controlled trial of oxycodone and of gabapentin for acute pain in herpes zoster. Pain. 2009 Apr. 142(3):209-17. [Medline].

  10. Klein NP, Fireman B, Yih WK, Lewis E, Kulldorff M, Ray P, et al. Measles-mumps-rubella-varicella combination vaccine and the risk of febrile seizures. Pediatrics. 2010 Jul. 126(1):e1-8. [Medline].

  11. Hviid A. Measles-mumps-rubella-varicella combination vaccine increases risk of febrile seizure. J Pediatr. 2011 Jan. 158(1):170. [Medline]. [Full Text].

  12. [Guideline] Marin M, Broder KR, Temte JL, Snider DE, Seward JF. Use of combination measles, mumps, rubella, and varicella vaccine: recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR Recomm Rep. 2010 May 7. 59:1-12. [Medline]. [Full Text].

  13. Tseng HF, Smith N, Harpaz R, et al. Herpes zoster vaccine in older adults and the risk of subsequent herpes zoster disease. JAMA. 2011 Jan 12. 305(2):160-6. [Medline].

  14. Schmader K, Levin M, Gnann J, McNeil S, Vesikari T, et al. Efficacy, immunogenicity, safety, and tolerability of zoster vaccine (ZV) in subjects 50 to 59 years of age (Poster/Abstract). Infectious Diseases Society of America. The 48th Annual Meeting of the Infectious Diseases Society of America. 10-21-2010. Vancouver, British Columbia, Canada:Ref Type: Abstract: 3363.

  15. Pierson DL, Mehta SK, Gilden D, et al. Varicella zoster virus DNA at inoculation sites and in saliva after Zostavax immunization. J Infect Dis. 2011 Jun 1. 203(11):1542-5. [Medline]. [Full Text].

  16. Galil K, Choo PW, Donahue JG, Platt R. The sequelae of herpes zoster. Arch Intern Med. 1997 Jun 9. 157(11):1209-13. [Medline].

  17. Rowbotham MC, Fields HL. The relationship of pain, allodynia and thermal sensation in post-herpetic neuralgia. Brain. 1996 Apr. 119 ( Pt 2):347-54. [Medline].

  18. Oaklander AL, Romans K, Horasek S, et al. Unilateral postherpetic neuralgia is associated with bilateral sensory neuron damage. Ann Neurol. 1998 Nov. 44(5):789-95. [Medline].

  19. Baik JS, Kim WC, Heo JH, Zheng HY. Recurrent herpes zoster myelitis. J Korean Med Sci. 1997 Aug. 12(4):360-3. [Medline].

  20. Carreau JP, Gola R, Cheynet F, Guyot L. [Zona of the cranial nerves. Current aspects]. Rev Stomatol Chir Maxillofac. 1998 Oct. 99(3):155-64. [Medline].

  21. [Guideline] Centers for Disease Control and Prevention (CDC); Advisory Committee on Immunization Practices (ACIP). Update: recommendations from the Advisory Committee on Immunization Practices (ACIP) regarding administration of combination MMRV vaccine. MMWR Morb Mortal Wkly Rep. 2008 Mar 14. 57(10):258-60. [Medline].

  22. Cohen JI. Varicella-zoster virus. The virus. Infect Dis Clin North Am. 1996 Sep. 10(3):457-68. [Medline].

  23. Cohen JI, Brunell PA, Straus SE, Krause PR. Recent advances in varicella-zoster virus infection. Ann Intern Med. 1999 Jun 1. 130(11):922-32. [Medline].

  24. Devinsky O, Cho ES, Petito CK, Price RW. Herpes zoster myelitis. Brain. 1991 Jun. 114 (Pt 3):1181-96. [Medline].

  25. Fabian VA, Wood B, Crowley P, Kakulas BA. Herpes zoster brachial plexus neuritis. Clin Neuropathol. 1997 Mar-Apr. 16(2):61-4. [Medline].

  26. Feder HM Jr, LaRussa P, Steinberg S, Gershon AA. Clinical varicella following varicella vaccination: don't be fooled. Pediatrics. 1997 Jun. 99(6):897-9. [Medline].

  27. Gilden DH, Cohrs RJ, Mahalingam R. VZV vasculopathy and postherpetic neuralgia: progress and perspective on antiviral therapy. Neurology. 2005 Jan 11. 64(1):21-5. [Medline].

  28. Goh CL, Khoo L. A retrospective study of the clinical presentation and outcome of herpes zoster in a tertiary dermatology outpatient referral clinic. Int J Dermatol. 1997 Sep. 36(9):667-72. [Medline].

  29. Goldman GS. Universal varicella vaccination: efficacy trends and effect on herpes zoster. Int J Toxicol. 2005 Jul-Aug. 24(4):205-13. [Medline].

  30. Hong JJ, Elgart ML. Gastrointestinal complications of dermatomal herpes zoster successfully treated with famciclovir and lactulose. J Am Acad Dermatol. 1998 Feb. 38(2 Pt 1):279-80. [Medline].

  31. Hovens MM, Vaessen N, Sijpkens YW, de Fijter JW. Unusual presentation of central nervous system manifestations of Varicella zoster virus vasculopathy in renal transplant recipients. Transpl Infect Dis. 2007 Sep. 9(3):237-40. [Medline].

  32. Liang MG, Heidelberg KA, Jacobson RM, McEvoy MT. Herpes zoster after varicella immunization. J Am Acad Dermatol. 1998 May. 38(5 Pt 1):761-3. [Medline].

  33. Mainka C, Fuss B, Geiger H, et al. Characterization of viremia at different stages of varicella-zoster virus infection. J Med Virol. 1998 Sep. 56(1):91-8. [Medline].

  34. Morgan R, King D. Characteristics of patients with shingles admitted to a district general hospital. Postgrad Med J. 1998 Feb. 74(868):101-3. [Medline].

  35. Nagel MA, Gilden DH. The protean neurologic manifestations of varicella-zoster virus infection. Cleve Clin J Med. 2007 Jul. 74(7):489-94, 496, 498-9 passim. [Medline].

  36. Rowbotham MC, Davies PS, Verkempinck C, Galer BS. Lidocaine patch: double-blind controlled study of a new treatment method for post-herpetic neuralgia. Pain. 1996 Apr. 65(1):39-44. [Medline].

  37. Sparks L, Russell C. The new varicella vaccine: efficacy, safety, and administration. J Pediatr Nurs. 1998 Apr. 13(2):85-94. [Medline].

  38. Stein GE. Pharmacology of new antiherpes agents: famciclovir and valacyclovir. J Am Pharm Assoc (Wash). 1997 Mar-Apr. NS37(2):157-63. [Medline].

  39. Sugisaki K, Yoshida H. Varicella zoster virus meningoencephalitis accompanied by sporadic skin lesions in an older immunocompetent adult. J Infect Chemother. 2007 Aug. 13(4):270-2. [Medline].

  40. Svozilkova P, Rihova E, Diblik P. Varicella zoster virus acute retinal necrosis following eye contusion: casereport. Virol J. 2005 Aug 31. 2:77. [Medline].

  41. Vu AQ, Radonich MA, Heald PW. Herpes zoster in seven disparate dermatomes (zoster multiplex): report of a case and review of the literature. J Am Acad Dermatol. 1999 May. 40(5 Pt 2):868-9. [Medline].

  42. Westenend PJ, Hoppenbrouwers WJ. [Fatal varicella-zoster encephalitis; a rare complication of herpes zoster]. Ned Tijdschr Geneeskd. 1998 Mar 21. 142(12):654-7. [Medline].

  43. Galetta KM, Gilden D. Zeroing in on zoster: A tale of many disorders produced by one virus. J Neurol Sci. 2015 Oct 3. [Medline].

Typical zoster in the vicinity of right popliteal fossa in a vertebral nerve L4 distribution.
Human herpesvirus (HHV) type 3. Intraoral herpes zoster closely resembles recurrent HHV-1 infection, but the lesions generally follow a dermatome and stop sharply at the midline, as shown here. However, the rules for common sites of occurrence of HHV-1 and HHV-3 often do not apply to patients who are immunocompromised. Courtesy of Sheldon Mintz, DDS.
All material on this website is protected by copyright, Copyright © 1994-2016 by WebMD LLC. This website also contains material copyrighted by 3rd parties.