Infected Amtrak rider triggers measles alert in 6 CA counties

State public health officials are warning about a possible measles exposure across multiple California counties after an infected passenger traveled across the country on trains and buses. The California Department of Public Health said the unvaccinated passenger traveled through the state using Amtrak trains and thruway buses with transfers in at least six counties: Alameda, Butte, Kern, Los Angeles, Sacramento and San Joaquin. Measles is a highly contagious viral disease. People who are not vaccinated, particularly young children and pregnant people, face the highest risk of severe illness and even death, according to officials. The passenger arrived in California from an Amtrak train to Los Angeles on Sept. 10, according to officials. After arriving in Los Angeles, they took a route to Bakersfield and then went to Stockton, Oroville, Sacramento, and Emeryville before leaving the state to Denver. Here is the route the passenger took: Sept.