Central Valley health officials monitoring farmworkers exposed to measles outbreak in ArizonaHealth officials are monitoring a group of about 140 farmworkers who traveled from Arizona to the Central Valley after being exposed to measles during an ongoing outbreak in that state. Health officials are monitoring a group of about 140 farmworkers who traveled from Arizona to the Central Valley after being exposed to measles during an ongoing outbreak in that state. Health officials are monitoring a group of about 140 farmworkers who traveled from Arizona to the Central Valley after being exposed to measles during an ongoing outbreak in that state. Health officials are monitoring a group of about 140 farmworkers who traveled from Arizona to the Central Valley after being exposed to measles during an ongoing outbreak in that state. FRESNO, Calif. (KFSN) -- Health officials are monitoring a group of about 140 farmworkers who traveled from Arizona to the Central Valley after being exposed to measles during an ongoing outbreak in that state.