Update on Human Rhinovirus and Coronavirus Infections

Abstract

Human rhinovirus (HRV) and coronavirus (HCoV) infections are associated with both upper respiratory tract illness ("the common cold") and lower respiratory tract illness (pneumonia). New species of HRVs and HCoVs have been diagnosed in the past decade. More sensitive diagnostic tests such as reverse transcription-polymerase chain reaction have expanded our understanding of the role these viruses play in both immunocompetent and immunosuppressed hosts. Recent identification of severe acute respiratory syndrome and Middle East respiratory syndrome viruses causing serious respiratory illnesses has led to renewed efforts for vaccine development. The role these viruses play in patients with chronic lung disease such as asthma makes the search for antiviral agents of increased importance.

Fig. 1

(A) Genome structures of SARS-CoV and MERS-CoV. The single-stranded, positive-sense coronavirus genomes encode the structural proteins (blue), membrane (M), spike (S), envelope (E), and nucleocapsid (N), two replicase polyproteins (purple), ORF1a and ORF1b, and unique accessory proteins (red) that perform important functions in coronavirus replication and pathogenesis, such as blocking the innate immune signaling pathway. (B) Transmission routes. SARS-CoV transmission is thought to be from bats harboring SARS-like viruses to palm civet cats, which infected humans. SARS-CoV could also have been transmitted from bats to humans directly. MERS-CoV is thought to be transmitted from camels to humans, with the possibility that at some point bats infected camels. The dashed line identifies a low-level transmission event, the thin solid line identified a potential transmission event, and the thick solid line identifies a probable transmission event. CoV, coronavirus; MERS, Middle East respiratory syndrome; SARS, severe acute respiratory syndrome. (Reproduced from Coleman CM, Frieman MB. Coronaviruses: important emerging human pathogens. J Virol 2014;88:5209. doi: 10.1128/JVI.03488-13 with permission of the American Society for Microbiology.)