California warns of measles exposure in six counties from unvaccinated train passenger
Health authorities work to notify people who were exposed to person who traveled through at least six counties

TL;DR
- An unvaccinated traveler exposed people to measles while traveling through at least six California counties via Amtrak and bus.
- The exposure route included travel from Los Angeles to various cities, eventually leaving California for Denver.
- Passengers on affected trains/buses and individuals in stations on specific dates may have been exposed.
- California health officials emphasize the safety and effectiveness of the MMR vaccine.
- Pennsylvania is experiencing a significant measles outbreak with hundreds of confirmed cases and multiple deaths.
- The US is facing its largest measles resurgence in over 30 years, linked to vaccine hesitancy.
- Questions are being raised about the US health secretary's actions and statements regarding measles deaths and the CDC's data collection methods.