2802. Occupational Exposure to the Ugandan Strain of Zika Virus in a Laboratory Worker in the United States: Clinical Presentation, Viral Persistence, and Antibody Response

Abstract

BackgroundA laboratory worker suffered an accidental needle stick resulting in infection with the Ugandan strain (MR766) of Zika virus (ZIKV), a strain that has rarely been studied in humans. We report the clinical presentation and outcomes, molecular and serological diagnostic results, and immunological response. A 34-year-old Brazilian-born female laboratory researcher, presented with malaise, skin rash, myalgia and joint pain 10 days after an accidental needle stick while inoculating a mouse with ZIKV-MR766. On physical examination she had bilateral maculopapular rash on the cheeks, and tender effusions at the metacarpal and proximal interphalangeal joints and ankles. Symptoms and signs resolved within 3 weeks. ZIKV infection was confirmed by Nucleic Acid Amplification Test (Lab Corp®) in urine. Serological testing using the ZIKV IgM ELISA test from Lab Corp®, and a confirmatory plaque reduction neutralization test (PRNT) in accordance with the Centers for Disease Control and Prevention (CDC), results were negative.MethodsWhole blood, plasma, urine, saliva, and a vaginal swab were collected from day (D) 14 post exposure (PE) to D104 PE. A novel, antibody competition-based ZIKV diagnostic test (highly specific for ZIKV antibodies) was performed in serum, and detection of ZIKV-MR766 genomic RNA was performed in all body fluids longitudinally.ResultsAntibody response revealed broad IgM response to both ZIKV-Paraiba (strain from the 2015 outbreak) and ZIKV-MR766 during the acute phase of the infection, suggesting cross-reactivity. There was no cross-reactivity against dengue or yellow fever viruses. An IgG response was detected against both ZIKV strains and increased until D104 PE. ZIKV RNA was detected in whole blood, saliva, urine, and the vaginal swab at D14 PE. At D20 PE, virus was only detectable in whole blood at a value of less than 37 copies per mL. At D23 PE, there was no detectable virus. (figure).ConclusionThis case highlights the potential for ZIKV occupational exposure. Findings may be useful for the development of diagnostic tests against ZIKV as we were able to accurately determine time of exposure, presence of virus in body fluids, development of symptoms, and antibody responses after a well-documented infection. Disclosures All authors: No reported disclosures.