Middle East Respiratory Syndrome (“MERS-CoV”), a coronovirus that causes respiratory illness in humans, was first reported in Saudi Arabia in 2012. As reported by the World Health Organization (“WHO”) more than 635 cases of MERS-CoV were recorded as of May 2014.
Camels have been repeatedly implicated in the spread of this virus even though there is little epidemiologic evidence proving that they are the source of the human infections.
The Office International des Epizooties (“OIE”), also called the “World Organisation for Animal Health,” cautions against concluding that camels are the source of human infections until the “epidemiological aspects of the disease, including its transmission and the potential relationship between human and animal infections with MERS-Co-V” are further investigated and better understood.
The CDC describes the transmission of the virus as spreading “from ill people to others through close contact, such as caring for or living with an infected person.”
Two reported cases in the U.S. have been traced back to Saudi Arabia.
It is not surprising that many assume the source of this newly emerging human disease began in camels. In 2003, another newly identified coronovirus, Severe Acute Respiratory Syndrome (“SARS”) was linked to exposure to animals. SARS ultimately killed 774 of the more than 8,000 people infected with that virus.
Overall, the link between animal and human disease is well known. According to the OIE, “[a]pproximately 60% of existing human pathogens and many of those that have appeared during the past 20 years, can be traced back to animals and several of them have a proven link with wildlife.”
But before panic sets in about potential exposure to MERS-CoV from camels, scientifically sound epidemiological investigations must be performed. Testing for the virus must be specific enough to confirm that it, and not a related virus, is present.
Recently, “[h]ealth experts and veterinarians called for stepped-up monitoring, investigations and immediate reporting of cases of . . . MERS-CoV during a meeting convened by the Food and Agricultural Organization (FAO) in Oman.” Any confirmed cases of MERS-CoV in animals are required to be reported to the international community if identified in an OIE-member country, “as an ‘emerging disease’ in accordance with article 1.1.3 of the OIE Terrestrial Animal Health Code.”
But that is only the first step in this investigation. Then scientists must link the virus in camels to respiratory illness in humans.
The proof that infected animals can spread the disease to humans is a critical component in determining the epidemiology of this newly emerging disease. Collaboration between human and animal health officials is critical for the success of such studies.