South Carolina's measles outbreak has surpassed the number of cases recorded in Texas in 2025, with health officials confirming 789 cases since September in the northwest Spartanburg County area[1]. The outbreak spread rapidly, with nearly 600 new cases in the last month[1]. Measles is a highly contagious disease caused by a virus that spreads through the air when an infected person breathes, sneezes, or coughs[1]. The MMR vaccine is the best way to protect against measles and stop the spread of the disease[3]. South Carolina has seen its worst measles outbreak in 30 years in 2025[4]. Across the United States, there were 2,255 measles cases in 2025, the worst since 1991, and three deaths, all unvaccinated[1]. The decline in vaccination rates in the United States is a major cause of the recent increase in measles cases[4].