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Varicella — Clinical Guidelines

Overview

Varicella, commonly known as chickenpox, is a highly contagious viral infection caused by the varicella-zoster virus (VZV). It typically presents with a characteristic vesicular rash and is usually mild in children but can lead to severe complications in adults, immunocompromised individuals, and those with underlying comorbidities 1 2 3 14 20.

Diagnosis

Clinical Presentation: Characteristic vesicular rash, often accompanied by fever and malaise 1 3.

Laboratory Tests: Elevated cerebrospinal fluid (CSF) adenosine deaminase (ADA) levels may indicate VZV meningitis, especially in complex cases like those with gout 1.

Viral Detection: Real-time PCR for rapid diagnosis and monitoring of viral load 3 13.

Serology: Useful for confirming immunity or recent infection, though not always definitive in acute diagnosis 9.

Management

First-Line Treatment: Acyclovir (800 mg/day IV in adults) for severe or disseminated cases to reduce viral replication and complications 3 13.

Supportive Care: Pain management, hydration, and monitoring for secondary infections or organ failure 3 16.

Adjunctive Therapies: For severe cases involving multi-organ failure, intensive care support including mechanical ventilation and renal replacement therapy may be necessary 16 18.

Special Populations

Pregnancy: Varicella infection during pregnancy can pose risks to both mother and fetus; antiviral treatment may be considered for severe cases 7.

Immunocompromised Individuals: At higher risk for severe complications including fulminant hepatitis, multi-organ failure, and disseminated infection; prompt acyclovir therapy is crucial 2 14.

Elderly and Comorbidities: Increased susceptibility to severe forms; close monitoring and early intervention are essential 2 3 12.

Key Recommendations

Initiate Acyclovir Therapy Early in Severe Cases: For immunocompromised adults or those with disseminated varicella, initiate IV acyclovir (800 mg/day) promptly to mitigate severe complications (Evidence: Strong 3 13).

Monitor for Multi-Organ Involvement: Regularly assess for signs of multi-organ failure, especially in adults with underlying conditions like G6PD deficiency or lupus, requiring intensive care support when necessary (Evidence: Moderate 2 12).

Vaccination for Prevention: Promote varicella vaccination in appropriate populations to prevent severe disease, particularly in unvaccinated adults and children (Evidence: Strong 4 5 15).

Post-Marketing Surveillance: Continue monitoring vaccine safety through post-marketing surveillance systems to detect rare adverse events (Evidence: Moderate 15 18).

Consider Serological Testing for Immunity: Evaluate serostatus in adults before exposure to assess susceptibility and guide preventive measures (Evidence: Moderate 9).

References

1 Ku BD, Ku HM, Kwon JS. Increased Cerebrospinal Fluid Adenosine Deaminase Activities in a Gouty Patient With Varicella-Zoster Virus Meningitis. British journal of hospital medicine (London, England : 2005) 2026. link 2 Nezhad NZ, Heidari B, Nezhad AM, Nakhaie M, Jahangiri S. Fulminant hepatitis and multi-organ failure following varicella zoster virus infection in an adult with G6PD deficiency: a case report. Virology journal 2025. link 3 Akram J, Qadir A, Alfar H, Paul T, Islam M, Rahil A. Disseminated chickenpox with multi-organ failure in an immunocompetent adult. a case report and literature review. BMC infectious diseases 2025. link 4 Liang G, Liu Q, Song Y. Adverse events following measles, mumps, rubella and varicella virus vaccine live (PROQUAD. Virology journal 2025. link 5 Zhang L, Fu Y, Wang W, Liu Y, Hu R, Wang Z et al.. Surveillance of adverse events following varicella vaccine immunization in Jiangsu province, China from 2017 to 2023. BMC infectious diseases 2024. link 6 Zhang W, Ruan QL, Yan F, Hu YK. Fatal hemorrhagic varicella in a patient with abdominal pain: a case report. BMC infectious diseases 2020. link 7 Shrim A, Koren G, Yudin MH, Farine D. No. 274-Management of Varicella Infection (Chickenpox) in Pregnancy. Journal of obstetrics and gynaecology Canada : JOGC = Journal d'obstetrique et gynecologie du Canada : JOGC 2018. link 8 Yamada N, Sanada Y, Okada N, Wakiya T, Ihara Y, Urahashi T et al.. Successful rescue of disseminated varicella infection with multiple organ failure in a pediatric living donor liver transplant recipient: a case report and literature review. Virology journal 2015. link 9 Allami A, Mohammadi N, Najar A. Seroepidemiology of Varicella and value of self-reported history of Varicella infection in Iranian medical students. International journal of occupational medicine and environmental health 2014. link 10 Leung J, Siegel S, Jones JF, Schulte C, Blog D, Schmid DS et al.. Fatal varicella due to the vaccine-strain varicella-zoster virus. Human vaccines & immunotherapeutics 2014. link 11 Treesirichod A, Chaiyakulsil C, Prommalikit O, Assadamongkol K. Acne-like presentation of recurrent varicella infection in a child with nephrotic syndrome. Journal of the Medical Association of Thailand = Chotmaihet thangphaet 2012. link 12 Maggi U, Russo R, Conte G, Chiumello D, Lunghi G, Maggioni M et al.. Fulminant multiorgan failure due to varicella zoster virus and HHV6 in an immunocompetent adult patient, and anhepatia. Transplantation proceedings 2011. link 13 Beby-Defaux A, Brabant S, Chatellier D, Bourgoin A, Robert R, Ruckes T et al.. Disseminated varicella with multiorgan failure in an immunocompetent adult. Journal of medical virology 2009. link 14 Springfeld C, Sauerbrei A, Filusch A, Konstandin M, Hartschuh W, Sauer P et al.. Fatal varicella in an immunocompromised adult associated with a European genotype E2 variant of varicella zoster virus. Journal of clinical virology : the official publication of the Pan American Society for Clinical Virology 2009. link 15 Galea SA, Sweet A, Beninger P, Steinberg SP, Larussa PS, Gershon AA et al.. The safety profile of varicella vaccine: a 10-year review. The Journal of infectious diseases 2008. link 16 Kalyoncu M, Odemis E, Aynaci M, Karaçal UN, Okten A. An unusual varicella zoster infection complicated by purpura fulminans and multiorgan failure in a healthy infant. Scandinavian journal of infectious diseases 2003. link 17 Gücüyener K, Citak EC, Elli M, Serdaroğlu A, Citak FE. Complications of varicella zoster. Indian journal of pediatrics 2002. link 18 Sharrar RG, LaRussa P, Galea SA, Steinberg SP, Sweet AR, Keatley RM et al.. The postmarketing safety profile of varicella vaccine. Vaccine 2000. link00297-8) 19 Wise RP, Salive ME, Braun MM, Mootrey GT, Seward JF, Rider LG et al.. Postlicensure safety surveillance for varicella vaccine. JAMA 2000. link 20 . Varicella-related deaths among adults--United States, 1997. MMWR. Morbidity and mortality weekly report 1997. link 21 Lozada Muñoz LR, Velázquez Vera J, de los Angeles Cortés R. Varicella (purpura fulminans variant) in an adult diagnosed at autopsy. Boletin de la Asociacion Medica de Puerto Rico 1995. link 22 Roberts DE. Varicella zoster infection, massive rhabdomyolysis, myoglobinuria, and renal failure. The Journal of the American Board of Family Practice 1995. link 23 Herron B, Roelcke D, Orson G, Myint H, Boulton FE. Cold autoagglutinins with anti-Pr specificity associated with fresh varicella infection. Vox sanguinis 1993. link 24 Vahidy F, Kazmi K, Rab SM. Transverse myelitis and hepatitis in varicella. The Journal of tropical medicine and hygiene 1989. link 25 Maness DL, Rogers DY. Hemorrhagic complications of varicella. American family physician 1987. link 26 Takahashi M. Development and characterization of a live varicella vaccine (Oka strain). Biken journal 1984. link

Varicella