Officials with the San Francisco Department of Health are reporting six confirmed measles cases in the Bay area in the past month.
All the cases were unvaccinated and were residents of Santa Clara County (5) and Alameda County (1).
One additional linked case has been confirmed in Nevada.
All cases are linked to an unvaccinated traveler who was exposed in Europe and developed measles after returning to the San Francisco Bay Area. Local health departments in the Bay Area are conducting contact investigations.
Measles is one of the most contagious of all infectious diseases; approximately 9 out of 10 susceptible persons with close contact to a measles patient will develop measles. The virus spreads when an infected person coughs or sneezes. The virus can live for up to 2 hours in the air or on surfaces.
People with measles usually have a rash, high fever, cough, runny nose, and red, watery eyes. Some people also get an ear infection, diarrhea, or a serious lung infection such as pneumonia. Although severe cases are rare, measles can cause swelling of the brain and death.