MERS-CoV antibody testing
Altogether 148 serum samples from sheep (n=55), goats (n=45), and cattle (n=48) were available in sufficient volumes to perform MERS-CoV antibody testing. MERS-CoV spike protein-based immunofluorescence assay (IFA) was done as described previously . Initial screening was performed with sample dilutions of 1:40, retesting of putative positive (questionable) samples was done with a dilution series of 1:10 – 1:320. Detection was facilitated using 1:200 dilutions of donkey-anti sheep, donkey-anti goat, or goat-anti bovine secondary antibodies, all labelled with Alexa Fluor 488 (Dianova, Hamburg, Germany).