24yo with pain in the arm...

A 24-year-old healthy man with no comorbid conditions started developing pain over the arm and forearm of the same side, extending to the thumb and index finger, 2 weeks after the first dose of inactivated virus vaccine. Two days later, he noticed small fluid-filled lesions over the arms and forearms in groups and red-coloured rash on the palms. Examination revealed lesions involving the C6–C7 dermatome. Whats is your diagnosis and treatment suggestion?