The Middle East Respiratory Syndrome—How Worried Should We Be?

Perlman, Stanley

A notable feature of the MERS-CoV infection is that the virus does not appear to induce an interferon (IFN) or proinflammatory innate immune response in primary human airway epithelial cells or in cultured cells (16, 17) . A relative lack of IFN induction is a common feature of all coronavirus infections and may reflect both specific virus-mediated inhibition of cytoplasmic RIG-I-like sensing pathways and general evasion of cytoplasmic sensors via sequestration of viral macromolecular proteins inside membranous structures. In any case, this feature may allow MERS-CoV replication in the host prior to initiation of the immune response, contributing to enhanced virus levels and poor outcomes. On the other hand, MERS-CoV is more sensitive to IFN treatment than are other coronaviruses, such as SARS-CoV, suggesting a possible therapeutic intervention in infected patients (16, 17) .