Formulations for immune prophylaxis:
(1) ZIG (zoster immune globulin): derived from patients with herpes zoster infections; must be administered within 96 hours of exposure to ensure efficacy
(2) VZIG (varicella-zoster immune globulin): must be administered within 96 hours of exposure to ensure efficacy
(3) ZIP (zoster immune plasma)
Exposure criteria:
(1) Exposure to a person with chickenpox or zoster and
(1a) continuous household contact
(1b) playmate for more than 1 hour indoors
(1c) hospital contact, such as sharing the same room or prolonged face-to-face contact
(1d) mother
(2) Time elapsed since exposure <= 96 hours (4 days), preferably <= 72 hours (3 days)
Candidates for passive immunization, provided a significant exposure has occurred
(1) immunocompromised, susceptible children
(2) immunocompetent, susceptible adolescents (>= 15 years of age) and adults, especially pregnant women
(3) newborn infants of mothers with onset of chickenpox < 5 days before or < 2 days after delivery
(4) hospitalized premature infant >= 28 weeks of gestation when mother has no history of chickenpox
(5) hospitalized premature infant < 28 weeks gestation and/or birthweight <= 1000 grams, regardless of maternal history
