Sampling
Sampling was performed at the largest national livestock market in the UAE, the Al Ain central market in the emirate of Abu Dhabi, in October 2019. The market is divided into three main areas, with mostly mixed sheep and goat pens located between camel and cattle stalls (Fig. 1). The distance between camel pens and the closest pens holding sheep and goats is approximately 20 m.
In total, we sampled 152 animals, which appeared healthy at the time of sampling. Nasal swabs and blood samples were taken from 55 sheep (41 female and 14 male) with an age range from three months to four years (mean of 19 months), and 45 goats (31 female and 14 male) from three to 40 months old (mean of 12 months). In addition, we collected blood samples from 52 cattle (43 female and nine male) from one to six years (mean of 3.8 years). Nasal swabs were collected in tubes containing a virus inactivation solution (DNA/RNA Shield, ZymoResearch, Irvine, CA, USA). Serum was separated from each blood sample by centrifugation. All samples were then stored at -80°C at the laboratory of the College of Medicine, Mohammed Bin Rashid University of Medicine and Health Sciences, Dubai, UAE, before shipment on dry ice to the University of Veterinary Medicine, Vienna, Austria, for virological and serological investigations.