[Source: US Centers for Disease Control and Prevention (CDC), Emerging Infectious Diseases Journal, full page: (LINK). Abstract, edited.]
Volume 25, Number 10—October 2019 / Research
Sensitive and Specific Detection of Low-Level Antibody Responses in Mild Middle East Respiratory Syndrome Coronavirus Infections
Nisreen M.A. Okba, V. Stalin Raj, Ivy Widjaja, Corine H. Geurts van Kessel, Erwin de Bruin, Felicity D. Chandler, Wan Beom Park, Nam-Joong Kim, Elmoubasher A.B.A. Farag, Mohammed Al-Hajri, Berend-Jan Bosch, Myoung-don Oh, Marion P.G. Koopmans, Chantal B.E.M. Reusken, and Bart L. Haagmans
Author affiliations: Erasmus Medical Center, Rotterdam, the Netherlands (N.M.A. Okba, V.S. Raj, C.H. Geurts van Kessel, E. de Bruin, F.D. Chandler, M.P.G. Koopmans, C.B.E.M. Reusken, B.L. Haagmans); Utrecht University, Utrecht, the Netherlands (I. Widjaja, B.-J. Bosch); Seoul National University College of Medicine, Seoul, South Korea (W.B. Park, N.-J. Kim, M.-D. Oh); Ministry of Public Health, Doha, Qatar (E.A.B.A. Farag, M. Al-Hajri)
Middle East respiratory syndrome coronavirus (MERS-CoV) infections in humans can cause asymptomatic to fatal lower respiratory lung disease. Despite posing a probable risk for virus transmission, asymptomatic to mild infections can go unnoticed; a lack of seroconversion among some PCR-confirmed cases has been reported. We found that a MERS-CoV spike S1 protein–based ELISA, routinely used in surveillance studies, showed low sensitivity in detecting infections among PCR-confirmed patients with mild clinical symptoms and cross-reactivity of human coronavirus OC43–positive serum samples. Using in-house S1 ELISA and protein microarray, we demonstrate that most PCR-confirmed MERS-CoV case-patients with mild infections seroconverted; nonetheless, some of these samples did not have detectable levels of virus-neutralizing antibodies. The use of a sensitive and specific serologic S1-based assay can be instrumental in the accurate estimation of MERS-CoV prevalence.
Keywords: MERS-CoV; Serology; Seroprevalence.