Zoonotic Transmission of Middle East Respiratory Syndrome Coronavirus from Camels to Humans and Barriers to Biosecurity Interventions in Jordan

Since the first detected cases of Middle East Respiratory Syndrome Coronavirus (MERS-CoV), a respiratory virus capable of causing severe human illness, surveillance and research have focused on identification of the source of primary human MERS-CoV infections. Within the One Health framework which recognizes the interconnectedness of human, animal, and environmental health, various animal hosts were investigated as sources of human infection because most emerging infectious diseases are zoonoses – pathogens spilling over from an animal host to a human. A systematic literature review was conducted to synthesize knowledge about MERS-CoV infections in livestock animals and zoonotic transmission of MERS-CoV to humans. Dromedary camels are the presumptive source of primary human MERS-CoV infections, but the importance, frequency, and specific mechanisms of camel-to-human MERS-CoV transmission have not been well characterized. Further, it is unknown what potential barriers will be faced when implementing basic biosecurity interventions to prevent zoonotic transmission at occupational sites where individuals regularly work or interact with dromedary camels. This dissertation addressed these knowledge gaps through a study of MERS-CoV serology and knowledge, attitudes, and beliefs about camel-to-human disease risks and basic biosecurity interventions in Jordan. This study detected individuals with low MERS-CoV neutralizing antibody titers in Jordan and found an association between regular work or interaction with dromedary camels or their living environments and evidence of MERS-CoV infection. Specific behavioral practices were not associated with evidence of MERS-CoV infection among those who regularly work or interact with dromedary camels or their living environments in Jordan. The study also identified multiple important barriers that may be faced when implementing basic biosecurity interventions in this population, including personal protective equipment (PPE) use and frequent handwashing. There were widespread ingrained beliefs that dromedary camels cannot transmit disease to humans and that camel milk and camel urine are beneficial to human health. Among camel workers, reported PPE use was low and frequent handwashing was uncommon. Only a few camel workers felt they would use PPE even if made freely available at their place of work. In conclusion, this dissertation provides further evidence that dromedary camel exposure is an important pathway in the epidemiology of primary human MERS-CoV infections in Jordan. The findings also support the notion that an intervention that simply provides basic biosecurity materials such as PPE and handwashing stations is likely to be ineffective in this population, and that identified barriers should be addressed to motivate behavioral change. Future studies are proposed including a longitudinal cohort study of individuals at risk for MERS-CoV that can detect individual seroconversion over time, track antibody responses among those who seroconvert, and evaluate key sub-exposures among those who are occupationally exposed to dromedary camels; as well as a pilot study to evaluate the feasibility, acceptability, and sustainability of a multifaceted biosecurity intervention that provides materials as well as training and education targeting the knowledge, attitude, and belief barriers identified.