Clinical and laboratory findings of the first imported case of middle east respiratory syndrome coronavirus to the United States

Background. The Middle East respiratory syndrome coronavirus (MERS-CoV) was discovered September 2012 in the Kingdom of Saudi Arabia (KSA). The first US case of MERS-CoV was confirmed on 2 May 2014. Methods. We summarize the clinical symptoms and signs, laboratory and radiologic findings, and MERS-CoV-specific tests. Results. The patient is a 65-year-old physician who worked in a hospital in KSA where MERS-CoV patients were treated. His illness onset included malaise, myalgias, and low-grade fever. He flew to the United States on day of illness (DOI) 7. His first respiratory symptom, a dry cough, developed on DOI 10. On DOI 11, he presented to an Indiana hospital as dyspneic, hypoxic, and with a right lower lobe infiltrate on chest radiography. On DOI 12, his serum tested positive by real-time reverse transcription polymerase chain reaction (rRT-PCR) for MERS-CoV and showed high MERS-CoV antibody titers, whereas his nasopharyngeal swab was rRT-PCR negative. Expectorated sputum was rRT-PCR positive the following day, with a high viral load (5.31 × 10⁶ copies/mL). He was treated with antibiotics, intravenous immunoglobulin, and oxygen by nasal cannula. He was discharged on DOI 22. The genome sequence was similar (>99%) to other known MERS-CoV sequences, clustering with those from KSA from June to July 2013. Conclusions. This patient had a prolonged nonspecific prodromal illness before developing respiratory symptoms. Both sera and sputum were rRT-PCR positive when nasopharyngeal specimens were negative. US clinicians must be vigilant for MERS-CoV in patients with febrile and/or respiratory illness with recent travel to the Arabian Peninsula, especially among healthcare workers.