Recurrent chickenpox infections are extremely rare because primary infection with varicella-zoster virus (VZV) typically confers lifelong immunity. When recurrent varicella (chickenpox) occurs, it is usually due to either an initial misdiagnosis, reinfection in immunocompromised individuals, or reactivation of latent virus manifesting as herpes zoster (shingles) rather than true recurrent chickenpox Products.
Causes of apparent recurrent chickenpox include:
- Immunosuppression: Individuals with compromised immune systems (due to conditions such as cancer, immunosuppressive therapy, or HIV) may have impaired immunity allowing either reinfection or atypical presentations of VZV infection Products; Tayyar & Ho 2023.
- False initial diagnosis or incomplete immunity: Some individuals may not develop full immunity after the first infection or vaccination, especially if the initial infection was mild or subclinical, potentially allowing reinfection Products; English 2003.
- Reactivation of latent virus: VZV remains dormant in dorsal root ganglia after primary infection and can reactivate later as herpes zoster, which is clinically distinct from chickenpox but may be confused with recurrent varicella Products; Arvin 1996.
True recurrent chickenpox is uncommon because the immune response to the primary infection usually prevents reinfection. However, in immunocompromised patients, the virus can cause more severe or atypical disease, including recurrent varicella-like illness Products; Tayyar & Ho 2023. The UK guidelines emphasize that a history of chickenpox or vaccination generally confers immunity, and recurrent chickenpox should prompt consideration of immune status and specialist referral Products; NICE CKS.