Most children with hand, foot and mouth disease have an oral rash or ulcers. It is painful to eat, and if you eat eggs it is recommended to cook them into an egg custard and serve them in a semi-fluid shape. Eggs themselves are rich in protein and can promote the repair of rashes and ulcers, so they are definitely okay to eat. Hand, foot and mouth disease is an infectious disease caused by enteroviruses, usually with an acute onset, mostly affecting children between six months and five years of age. The disease is self-limiting, with most children recovering from mild cases within a week or so, and only about 2% of children developing severe HFMD.