You can thank the anti-vaccination movement for much of this: Reported outbreaks of measles (red), mumps (brown), and whooping cough (green) in the U.S. from 2008 to this year.

By Michael Hiltzik

February 19, 2014, 2:18 p.m.

In yet another sign of the perils and irresponsibility of the anti-vaccination movement, thousands of riders of the Bay Area Rapid Transit system are being warned that they may have been exposed to measles — a disease that was declared eliminated in the U.S. in 2000 but has since returned.

The latest threat comes from an unnamed and unvaccinated UC Berkeley student who apparently contracted the disease while traveling in the Philippines during an outbreak there. Public health officials in Contra Costa County say people who rode BART during the morning or evening rush hours from Feb. 4 through Feb. 7 may have been exposed by the carrier, who is unidentified.

That could be hundreds of thousands of people. Health officials say those who have been immunized or have had the disease are probably still protected. But measles is highly communicable, and many unprotected individuals who came in contact with the source could become infected.

More: The Anti-Vaccination Movement Brings the Measles Threat Back Home