Measles causes a fever, rash and cough, among other symptoms, and can be particularly harmful for babies and young children, according to the Centers for Disease Control and Preve

According to the society, the last US measles death was in 2015. A measles infection can have particularly devastating complications for pregnant women and young children, including pneumonia, neurological impairment, hearing loss and death.

An unvaccinated child has died as the Texas measles outbreak reaches 124 cases. Public health officials also warn of potential spread in San Marcos and San Antonio.