Lynne, disease is definitely an issue, albeit remote - heavy gloves advised because, obviously, they can bite and are known to carry a variety of bacteria which is known to cause osteomyelitis. This can seriously inconvenience you. Probably over-cautious, but having had a fox bite clean through heavy bridle leather (it appeared to be trying to take it away for reasons best known to itself...), you'll be in a better condition to look after it if it doesn't fang you. Sarcoptic mange is otherwise known as scabies - it's not difficult to treat if you can make the animal amenable to treatment, but it is transmissable to peoples.
Good luck to you and the fox.