A measles outbreak in South Carolina that infected nearly 1,000 people has officially ended, health officials announced. The outbreak represents the largest measles outbreak in recent United States history.

Measles is a highly contagious viral disease that can cause serious complications, particularly in young children, pregnant women, and immunocompromised individuals. The disease spreads through respiratory droplets when infected individuals cough or sneeze.

The outbreak's scale underscores ongoing public health challenges related to vaccine-preventable diseases. Measles was declared eliminated from the United States in 2000, meaning the disease was no longer continuously transmitted within the country, though isolated cases and small outbreaks have occurred since then.

Health officials typically declare an outbreak over when no new cases have been reported for two incubation periods of the disease, which for measles is approximately 42 days. The measles vaccine is highly effective at preventing the disease when administered according to recommended schedules.