South Carolina reported a rapid spread of measles, with the total number of cases reaching 558, according to state officials on Friday. The outbreak, which is the largest in the United States, has nearly doubled in the last week.

The South Carolina Department of Health and Environmental Control (SCDHEC) reported 124 new measles cases in the last three days alone. Dr. Helmut Albrecht, an infectious disease physician with Prisma Health and the University of South Carolina School of Medicine, stated in a briefing that the situation is expected to worsen before it improves. Hundreds of individuals across the state are currently under quarantine or isolation due to potential exposure.

The epicenter of the outbreak is located in Spartanburg County, in the northwestern region of South Carolina. Health officials are investigating the factors contributing to the rapid spread, including a notable increase in nonmedical exemptions from required school vaccinations in the area since the pandemic. New research published this week is examining the correlation between vaccine exemption rates and the measles outbreak.

Measles is a highly contagious viral disease that can cause severe health complications, including pneumonia, encephalitis (brain swelling), and even death. The measles, mumps, and rubella (MMR) vaccine is highly effective in preventing measles infection. Public health experts emphasize that widespread vaccination is crucial to achieving herd immunity and protecting vulnerable populations, such as infants who are too young to be vaccinated and individuals with compromised immune systems.

SCDHEC is urging residents to ensure they and their children are up-to-date on their MMR vaccinations. The agency is also working to provide information and resources to healthcare providers and the public to help control the outbreak. Individuals who suspect they may have measles are advised to contact their healthcare provider immediately and to isolate themselves to prevent further spread of the virus.