A child presents with fever and vesicular rashes on the hands, feet, and mouth. Which pathogen is most responsible for this presentation?

Hand, Foot, and Mouth Disease (HFMD) is a highly contagious viral illness most commonly caused by Coxsackievirus A16 (and Enterovirus 71) in children. It presents with: fever, painful vesicular lesions/ulcers on the oral mucosa (tongue, buccal mucosa, palate), and a maculopapular/vesicular rash on the palms, soles, and sometimes the buttocks. It is self-limiting and requires only supportive care. HSV-1 causes herpetic gingivostomatitis (oral lesions only). Measles causes Koplik spots (white oral lesions), not vesicular rash. Rubella causes a systemic maculopapular rash without the characteristic HFMD distribution.