Healthcare-associated Exposure to the Varicella-Zoster Virus (VZV)
The VZV is transmitted from person-to-person primarily by direct contact with vesicular fluid; inhalation of droplet nuclei from infected respiratory secretions; and less frequently, by contact with freshly contaminated articles and environmental surfaces. If VZV exposure occurs in a healthcare setting, all case-patient contacts should be evaluated immediately for presumptive evidence of immunity.13 Persons are considered immune only if they have documentation of:
physician-diagnosed varicella (chickenpox)
physician-diagnosed herpes zoster
laboratory evidence of VZV immunity
age-appropriate vaccination against the VZV.
All susceptible HCP exposed to the VZV should receive PEP with two subcutaneous doses (4-8 weeks apart) of the varicella-zoster vaccine (Varivax) as soon as possible, but ideally no later than 120 hours of an exposure.12 HCP who have received the vaccine more than 5 days after the exposure should be excluded from duty for 8-21 days after exposure.12
Susceptible HCP exposed to the VZV for whom the vaccine is contraindicated should be administered varicella-zoster immunoglobulin (VZIG) no later than 96 hours of an exposure.12 This recommendation also applies to women exposed to the VZV at any stage of pregnancy. The VZIG product currently used in the United States is VariZIG™.