Validity of self-reported varicella disease history in pregnant women attending prenatal clinics.
OBJECTIVE
The purpose of this study was to assess the validity of self-reported history for varicella disease relative to serological evidence of varicella immunity in pregnant women attending antenatal care at clinics located in two diverse geographical locations in the U.S. (Antelope Valley, California, and Philadelphia) with high varicella vaccination coverage.


METHODS
Pregnant women attending prenatal care appointments who needed blood drawn as part of their routine care were eligible to participate. Self-reported varicella disease history was obtained via questionnaire. Varicella serostatus was determined using a whole-cell enzyme-linked immunosorbent assay to test for varicella zoster virus-specific immunoglobulin G (VZV IgG) antibodies.


RESULTS
Of the 309 study participants from Antelope Valley and the 528 participants from Philadelphia who self-reported having had chickenpox disease, 308 (99.7%; 95% confidence interval [CI]: 98.2, 100) and 517 (97.9%; 95% CI: 96.3, 99.0), respectively, had serological evidence of immunity to varicella. Only 6.8% (95% CI: 3.9, 11.0) and 17.4% (95% CI: 13.1, 22.5) of women who self-reported having a negative or uncertain varicella disease history in Antelope Valley and Philadelphia, respectively, were seronegative for varicella antibodies.


CONCLUSIONS
Despite the dramatic changes in the epidemiology of varicella that have occurred since 1995 due to the introduction and subsequent widespread use of the varicella vaccine, self-reported history of varicella continues to be a strong predictor of VZV IgG antibodies in pregnant women. Negative or uncertain history remains poorly predictive of negative serostatus.
Watson
Barbara
B
Philadelphia Department of Public Health, 500 South Broad St., Philadelphia, PA 19146, USA. barbara.watson@phila.gov
Civen
Rachel
R
Reynolds
Meredith
M
Heath
Karl
K
Perella
Dana
D
Carbajal
Tina
T
Mascola
Laurene
L
Jumaan
Aisha
A
Zimmerman
Laura
L
James
Abike
A
Quashi
Carlene
C
Schmid
Scott
S
D000293:Adolescent; D000328:Adult; D000914:Antibodies, Viral / Q000097:blood; D002644:Chickenpox / Q000097:blood / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D008875:Middle Aged; D011247:Pregnancy; D011295:Prenatal Care; D015203:Reproducibility of Results; D012698:Serologic Tests
D000914:Antibodies, Viral