MANAGEMENT OF PREGNANT WOMEN EXPOSED

TO VARICELLA (IMMUNE STATUS UNKNOWN)

Exposure To Varicella
ß

IgG + IgM -	IgG + or IgG- IgM +	IgG - IgM -
Past Infection ß	Recent Infection ß	Not Immune ß
Immune Reassure Patient	Watch for pneumonia in mother ß	Give VzIg within 96 hrs of exposure

ß

< 20 weeks gestation	If rash develops < 5 days before or < 2 days after delivery
* Counsel for embryopathy (2.2% risk) * Refer for detailed ultrasound at 16-20 weeks * Neonatal ophthalmologic examination after birth	* 20% risk of neonatal varicella (30% mortality) * Give VzIg to infant

* IgG = Immunoglobulin G.
* IgM = Immunoglobulin M.
* VzIg = Varicella zoster immunoglobulin.

If possible, birth should be delayed until at least 5 days after the onset of the mother's illness. Administering VZIG to neonates born to mothers with onset of disease 5 days before to 2 days after delivery significantly reduces newborn complications, even though it does not entirely prevent mortality or alter the attack rate. Although neonates born to mothers experiencing varicella more than 5 days before or more than 2 days after delivery are not at increased risk for complications, some experts recommend VZIG in this setting, too. Some pediatric infectious disease experts may give acyclovir preemptively to exposed newborns, especially if birth occurs preterm.

VZV vaccination prior to pregnancy or postpartum is increasingly considered as a way to decrease susceptibility to VZV-induced maternal, fetal, and neonatal morbidity and to mitigate excess costs and liability. Such strategies will likely prove most effective in groups of women who are serosusceptible and at high risk of exposure (child-care providers, health-care providers) and in those who are at higher risk of severe disease (immunosuppressed). The present varicella vaccine employs the live Oka strain and should not be used in pregnancy.

REFERENCES

1. Crane JMG. Prenatal exposure to viral infections. Can J of CME 1988:61-74.
2. Centers for Disease Control and Prevention. Prevention of varicella: recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR. 1996;45(RR-11):1-36.
3. Feder HM Jr. Treatment of adult chickenpox with oral acyclovir. Arch Intern Med. 1990;150:2061-2065.
4. Haake DA, Zakowski PC, Haake DL, et al. Early treatment with acyclovir for varicella pneumonia in otherwise healthy adults: retrospective controlled study and review. Rev Infect Dis. 1990:12:788-789.
5. Landsberger EJ, Hager WD, Grossman JH 3d. Successful management of varicella pneumonia complicating pregnancy. A report of three cases. J Reprod Med. 1986;31:311-314.
6. Paryani SG, Arvin AM. Intrauterine infection with varicella-zoster virus after maternal varicella. N Engl J Med. 1986;314:1542-1546.
7. Rajan P, Rivers JK. Varicella zoster virus. Recent advances in management. Can Fam Physician. 2001;47:2299-2304. Review.
8. Shields KE, Galil K, Seward J, et al. Varicella vaccine exposure during pregnancy: data from the first 5 years of the pregnancy registry. Obstet Gynecol. 2001;98:14-19.
9. van Der Zwet WC, Vandenbroucke-Grauls CM, van Elburg RM, et al. Neonatal antibody titers against varicella-zoster virus in relation to gestational age, birth weight, and maternal titer. Pediatrics. 2002;109:79-85.