By July 2015, MERS-CoV cases had been reported in over 21 countries, in Europe, North America and Asia as well as the Middle East.

[11] Egyptian virologist Ali Mohamed Zaki isolated and identified a previously unknown coronavirus from the man's lungs.

[11] Among animal reservoirs, CoV has a large genetic diversity yet the samples from patients suggested a similar genome, and therefore common source, though the data were limited.

It was determined through molecular clock analysis that viruses from the EMC/2012 and England/Qatar/2012 date to early 2011, suggesting that these cases were descended from a single zoonotic event.

It appeared the MERS-CoV had been circulating in the human population for more than a year without detection, and suggested independent transmission from an unknown source.

[20][21] Due to the clinical similarity between MERS-CoV and SARS-CoV, it was proposed that they may use the same cellular receptor; the exopeptidase, angiotensin converting enzyme 2 (ACE2).

As would be expected, the amino acid sequence of DPP4 is highly conserved across species and is expressed in the human bronchial epithelium and kidneys.

[25] On 13 February 2013, the World Health Organization stated that "the risk of sustained person-to-person transmission appears to be very low.

It is possible for MERS to be symptomless, and early research has shown that up to 20% of cases show no signs of active infection but have MERS-CoV antibodies in their blood.

[citation needed] Examination of the sequences of 238 isolates suggested that this virus has evolved into three clades differing in codon usage, host, and geographic distribution.

[43] Countries like Saudi Arabia and the United Arab Emirates produce and consume large amounts of camel meat.

[44] In 2013 MERS-CoV was identified in three members of a dromedary camel herd held in a Qatar barn, which was linked to two confirmed human cases who have since recovered.

[47] On 6 June 2014, the Arab News newspaper highlighted the latest research findings in the New England Journal of Medicine in which a 44-year-old Saudi man who kept a herd of nine camels died of MERS in November 2013.

His friends said they witnessed him applying a topical medicine to the nose of one of his ill camels—four of them reportedly sick with nasal discharge—seven days before he himself became stricken with MERS.

"[54] Dr. Zaki was fired from his job at the hospital as a result of bypassing the Saudi Ministry of Health in his announcement and sharing his sample and findings.

[55][56][57][58] At their annual meeting of the World Health Assembly in May 2013, WHO chief Margaret Chan declared that intellectual property, or patents on strains of new virus, should not impede nations from protecting their citizens by limiting scientific investigations.

[59] Erasmus MC responded that the patent application did not restrict public health research into MERS and MERS-CoV,[60] and that the virus and diagnostic tests were shipped—free of charge—to all that requested such reagents.