South Carolina measles outbreak spreads to Washington with five new cases

South Carolina’s measles outbreak jumped to Washington state five times in two weeks, health officials said on Tuesday, marking the first time the disease has moved across the country at that speed since the pandemic‑era decline in international travel. The cases were identified in three counties in western Washington, all linked to travelers who had recently visited the Charleston area where the outbreak began in early August. The Washington State Department of Health confirmed that all five patients tested positive for the measles virus within a 10‑day span.

The shift matters because measles was once considered eliminated in the United States, thanks to high vaccination rates and strict border screening. In recent years, most U.S. cases were imported by travelers returning from countries where the disease is still endemic. That pattern changed last month when a cluster of unvaccinated children in South Carolina sparked a local surge, prompting the CDC to issue an advisory. Low vaccination coverage in certain communities, fueled by misinformation and vaccine hesitancy, created a pocket of susceptibility that allowed the virus to spread unchecked. The outbreak coincided with a regional music festival that attracted out‑of‑state visitors, providing a conduit for the disease to travel inland.

The CDC reports that the South Carolina cluster involved 27 confirmed cases, with 19 of those in children under five who had not received two doses of the MMR vaccine. In Washington, the five new cases are the first measles infections in the state since 2019, and all patients are currently in isolation. State health officials have begun contact tracing and are urging anyone who attended the same events or who has not been vaccinated to get a dose of MMR immediately. Local hospitals have stocked additional vaccine doses and are prepared to treat complications such as pneumonia or encephalitis.

Health authorities say the outbreak underscores the need for nationwide vigilance. The CDC will continue to monitor the situation and may expand its travel advisory if more states report linked cases. Officials are urging schools and workplaces to verify immunization records and to offer on‑site vaccination clinics. If vaccination rates rise above the 95 % threshold needed for herd immunity, experts say the virus will struggle to find new hosts and future cross‑state jumps could be prevented.