Unvaccinated measles passenger rode Amtrak through SIX California counties as fourth US death is confirmed
From the Newshound archive · first published 19 September 2026 · last updated 20 September 2026.
An unvaccinated traveller arrived in Los Angeles from Chicago on 12 September, triggering a measles exposure alert spanning six California counties and extending to Colorado.
An unvaccinated passenger carrying measles travelled by Amtrak train and thruway bus across California before being hospitalised, setting off a widespread public health notification. Arriving from Chicago in Los Angeles on 10 September, the individual continued north through Bakersfield, Stockton, Oroville, Sacramento and Emeryville, then departed for Denver. Authorities are now working urgently to identify and contact the thousands of passengers who may have been exposed. The warning follows Pennsylvania's confirmation of a fourth measles-related death during the worst US measles resurgence since 1991.
The infected passenger moved through Alameda, Butte, Kern, Los Angeles, Sacramento and San Joaquin counties over five days before crossing into another state.
California's assistant health officer Dr Rita Nguyen cautioned that measles 'can lead to severe life-long consequences including permanent brain damage and can also be fatal, especially for children.'
The US has now recorded 3,471 confirmed measles cases this year across 45 states and Washington DC, the highest caseload since 1991.
