child with vesicle on the hard palate with history of malaise for 3 days what is the possible diagnosis.. herpes simplex child with vesicle on the hard palate with history of malaise for 3 days what is the possible diagnosis: 1- herpes simplex.*** 2- erythema multiform. Share This: Facebook Twitter Google+ Stumble Digg Email ThisBlogThis!Share to XShare to Facebook