A 6-year-old girl from Delhi presents with her father reporting a 5-day history of painful pustules on her right forearm and hand. The lesions began as small red papules that progressed to pustules with surrounding erythema and edema. The child had a minor abrasion from a playground fall 2 days before the rash appeared. On examination, she has multiple pustules with purulent drainage, some coalescing into larger lesions. The regional lymph nodes (epitrochlear and axillary) are enlarged and tender. There is no systemic fever or constitutional symptoms. A culture from the pustule grows methicillin-sensitive *Staphylococcus aureus* (MSSA). The child's mother reports that the girl had a similar episode 6 months ago that resolved with oral antibiotics. What is the most appropriate management to prevent recurrence?