Searching for the Animal Reservoir(s) of MERS-CoV

The World Organisation for Animal Health (OIE), organized in the 1920s, is an international organization of member countries established to promote global transparency of animal diseases, to collect scientific information relating to international animal disease control, and to develop standards for international trade of animals and animal products. The OIE is also tasked with disseminating information about emerging zoonotic diseases that have the potential for transmission to humans.

Recently, the OIE provided a summary of its current understanding of the Middle East Respiratory Syndrome Coronavirus (MERS-CoV) in Update August 2014 - Questions & Answers on Middle East Respiratory Syndrome Coronavirus (MERS-CoV). This update provides general information about the MERS-CoV, but also has a detailed discussion about potential animal reservoirs for this coronavirus.

Several patterns or mode of human transmission of MERS have been identified by the World Health Organization. Human MERS infections can be transmitted in hospital settings and through close human to human contact. Both of these transmission settings require an infected individual. It is uncertain how the initial MERS cases in these situations became infected. These sporadic or community acquired infections could result from an environmental source or direct or indirect contact with animals.

The OIE points out that there is strong evidence that camels may be an animal host for this coronavirus, but perhaps not the only host. A number of confirmed MERS human cases had contact with camel or exposure to camels or camel products prior to infection. But not all sporadic MERS cases can be linked to camel or camel product exposure. The OIE specifically states “there remains the possibility that other animal species may be involved in the maintenance and transmission of the MERS-CoV”. The OIE concludes that more scientific research is necessary to determine whether other animal species, besides camels, may represent primary or intermediate hosts for MERS-CoV.