The strain of H5N1 avian influenza circulating in the US is extremely contagious among birds and has infected mammals, “which gives me a little pause for humans,” and anyone working closely with birds should get a flu vaccine, said epidemiologist Maurice Pitesky of the University of California at Davis School of Veterinary Medicine. H5N1 may be spreading more through contact with feces than respiratory droplets, but regardless, it’s never a good idea to get too close to a bird with a virus, and anyone who must have contact with an infected animal should wear a mask, gloves and other protective equipment, says veterinarian Jim Wellehan, an associate professor at the University of Florida College of Veterinary Medicine.