Objective: To describe a single U.S. perinatal center's ongoing experience with evaluating pregnant patients with potential exposure to Zika virus infection.
Methods: This is an institutional review board-approved longitudinal observational study from January to August 2016 from a single perinatal referral center. Patients who had traveled to or had sexual contact with a person who traveled to a region with documented local Zika virus transmission were included in the study. The aim of the study was to identify the rate of confirmed infection among pregnant women referred to our center with established risk factors for Zika virus acquisition. We also sought to characterize travel patterns that constituted risk, to identify rates of symptoms suggesting infection, and to potentially describe findings suggestive of congenital Zika virus infection in prenatal ultrasound evaluations.
Results: We evaluated 185 pregnant women with potential Zika virus exposure. Testing was offered in accordance with the version of the Centers for Disease Control and Prevention guidelines in place at the time of the consultation visit. Geographic exposure data showed Mexico (44%), the Caribbean (17%), North America (16%), South America (13%), and Central America (9%) to be the most common areas in which potential exposure occurred. One hundred twenty-three (67%) patients reported insect bites and 19 (10%) patients reported symptoms. Overall, five (3% of all) patients had prenatal ultrasound findings suggestive of possible fetal Zika virus infection; all their Zika virus test results returned negative. These findings included microcephaly, echogenic intracardiac foci, and ventricular calcifications. Of the 153 Zika virus screening tests ordered, eight (5%) immunoglobulin M results returned positive or equivocal with only one positive through confirmatory testing. Overall, 1 of 185 (0.5%) of all those consulted and 1 of 153 (0.7%) of those tested had a confirmed Zika virus infection with no confirmed fetal or neonatal infections.
Conclusion: We identified low rates of confirmed maternal Zika virus infection in our cohort, but the number of patients described here demonstrates the magnitude of concern existing among both patients and physicians regarding possible perinatal Zika virus infection. It also underscores the need for health care providers to be prepared to answer questions, explain laboratory and ultrasound results, and describe testing options for concerned patients and their families.