HOUSTON, Aug. 18 (Xinhua) -- Health authorities in the U.S. state of Texas have issued a measles alert due to a sharp increase of cases this year. About a dozen people have been confirmed to have measles in Texas so far this year, local media outlet Houston Chronicle on Sunday quoted state health authorities as saying. Texas had six reported cases of measles in 2011, while no cases were reported in 2012, according to the report. Given the alarming rise, state health officials are urging immunization and asking health care providers to watch for potential exposures and patients with measles...