Gloves
The use of gloves is prudent in many search circumstances to avoid contact with poison oak, getting cut on rusty fence wire, handling objects of unknown origin, and of course handling dogs. A skittish dog may be skeptical while taking a treat from a gloved hand, but if you must actually handle a dog wearing gloves is the best approach. There are gloves advertised as "bite proof", but if you find yourself in those conditions you really shouldn't be handling the dog anyway. A common glove with a blend of fabric, and leather will suffice to lessen to impact of an unexpected bite - or at the very least, reduce the seriousness of a bite by some degree.