Emerging Infectious Diseases (Oct 2019)

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,
  • Bart L. Haagmans

DOI
https://doi.org/10.3201/eid2510.190051
Journal volume & issue
Vol. 25, no. 10
pp. 1868 – 1877

Abstract

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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.

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