A school-age child in California has died from a rare complication of measles contracted as an infant. Los Angeles County health officials announced the death Thursday.

A school-age child has died from a rare complication of measles contracted in infancy, Los Angeles County health officials said Thursday.

The child, who had been too young to be vaccinated when they were infected by the virus, died of subacute sclerosing panencephalitis, according to the county health department. The incurable disorder causes progressive brain damage and is nearly universally fatal.

About 1 in 10,000 people who get measles develops the disorder, but the risk is 1 in 600 for infants.