Persistence of protective immunity after postexposure prophylaxis of varicella with oral aciclovir in the family setting

Abstract

The persistence of protective immunity after postexposure prophylaxis against varicella using oral aciclovir was evaluated in the family setting. Sixty one of 78 recipients of oral aciclovir were assessed by questionnaire, and 13 of 61 were evaluated for serum antibody to varicella zoster virus (VZV) using the fluorescent antibody to membrane antigen method. The observation period ranged from 33 to 50 months. None of those (n = 44) who had initially seroconverted to VZV after aciclovir prophylaxis developed breakthrough varicella. All 13 who had serology repeated still had titres > 4. Antibody titres in those who had histories of re-exposure to the virus were significantly higher than in those who had not (p<0.01).

Aciclovir and Varicella-zoster-immunoglobulin in solid-organ transplant recipients

“…Studies revealed that the use of aciclovir prophylaxis in immunocompetent children exposed to a household contact with active varicella significantly decreased the transmission rate of VZV [27][28][29]. Most important for cases of reexposure, these children developed subclinical infection with a prolonged humoral immunity against VZV [29].…”

Chickenpox in the immunocompromised child

“…If prophylaxis is delayed until day 11, varicella is not prevented, perhaps because viral replication rate and viraemia is past its peak by then 14. Studies suggest that aciclovir interferes with viral replication sufficiently to suppress clinical disease while still allowing effective immunity to develop 15–17. Many departments have already changed their practice and now use aciclovir instead of VZIG 18.…”

Profylaktisk behandling etter varicellaeksponering

“…Norsk barnelegeforening anbefaler en profylaksevarighet på 14 dager fra dag 7 (12). Det er viktig å sjekke immunstatus etter profylakse for å undersøke om pasienten trenger vaksinasjon (18,31). Hvorvidt immunresponsen etter en subklinisk infeksjon i forbindelse med aciklovirprofylakse er nok til å beskytte mot senere infeksjoner og utvikling av zoster, er ikke godt nok studert.…”

“…Hvorvidt immunresponsen etter en subklinisk infeksjon i forbindelse med aciklovirprofylakse er nok til å beskytte mot senere infeksjoner og utvikling av zoster, er ikke godt nok studert. Små observasjonsstudier tyder på at immuniteten holder seg i alle fall i 2 1 /2-3 år hos friske barn (18,31).…”