A novel human coronavirus: Middle East respiratory syndrome human coronavirus

Geng, HeYuan; Tan, WenJie

In June 2012, a Saudi man in his sixties got an acute respiratory tract infection in Saudi Arabia with symptoms of fever, cough, expectoration and shortness of breath. The patient who was previously well, was severely ill and presented with acute pneumonia and later renal failure with a fatal outcome 11 days after hospitalization [10] . Clinical specimens were collected and the patient's sputum was used to inoculate Vero and LLC-MK2 cells for viral culture. Cytopathic effect (CPE) was observed and, upon passaging of the culture supernatant to fresh cells, the same CPE was observed, suggesting viral replication. All known respiratory tract pathogens including the influenza A virus, influenza B virus, adenovirus, enterovirus, parainfluenza viruses types 13, respiratory syncytial virus, human metapneumovirus, human bocavirus, rhinovirus, and human herpesvirus types 13 were tested and all yielded negative results from the sputum and cell culture supernatant. However, the pancoronavirus real-time reverse transcription polymerase chain reaction (RT-PCR) assay used to detect coronaviruses revealed the expected size of the PCR fragments, and found that they corresponded to a conserved region of ORF1b of the replicase gene of a coronavirus. Phylogenetic analysis of this fragment with other known coronaviruses genes showed that this novel virus together with the bat coronaviruses HKU4 and HKU5 belonged to subgroup 2c of the linage Betacoronavirus, indicating the emergence of a novel coronavirus [11] . The complete genome of the virus was subsequently sequenced at the Erasmus Medical Cerner (EMC) in Rotterdam in the Netherlands and was named human coronavirus EMC (HCoV-EMC), later named MERS-CoV (GenBank accession number: JX869059).