Detection of the Middle East Respiratory Syndrome Coronavirus Genome in an Air Sample Originating from a Camel Barn Owned by an Infected Patient

Azhar, Esam I.; Hashem, Anwar M.; El-Kafrawy, Sherif A.; Sohrab, Sayed Sartaj; Aburizaiza, Asad S.; Farraj, Suha A.; Hassan, Ahmed M.; Al-Saeed, Muneera S.; Jamjoom, Ghazi A.; Madani, Tariq A.

Although the source of MERS-CoV and its mode of transmission are not fully understood, zoonotic transmission from an unknown reservoir or through an intermediate host to humans was suggested (7) (8) (9) . Phylogenetic analysis showed that MERS-CoV belongs to bat-associated clade 2c betacoronaviruses (2, 9, 10) . Detection of MERS-CoV-related viruses in Old World insectivorous bats from the family Vespertilionidae (11, 12) and the isolation of small genomic fragments identical to the sequence of the Erasmus Medical Center (EMC)/2012 MERS-CoV Essen isolate (GenBank accession number KC875821) from a Taphozous perforatus bat in Saudi Arabia (13) suggested that insectivorous bats could be the original source of MERS-CoV. However, due to the limited direct contact between humans and bats and to the detection of neutralizing antibodies to MERS-CoV in dromedary camels from countries like Oman, the United Arab Emirates, Qatar, Egypt, and Saudi Arabia (8, (14) (15) (16) , dromedary camels were proposed to be involved in the cross-species transmission of MERS-CoV. This was further supported by the detection and partial genome sequencing of MERS-CoV RNA in samples collected from camels in Qatar and Saudi Arabia (17, 18) . Anti-MERS-CoV antibodies have also been detected in samples collected from dromedary camels in Saudi Arabia since 1992 (18) . While these studies provide a convincing link between humans, camels, and MERS-CoV and indicate that MERS-CoV has been circulating in dromedary camels for a long time, they do not prove that camels passed the virus to humans.