Americans returning home from Thanksgiving break faced strict new coronavirus measures around the country Monday as health officials brace for a disastrous worsening of the out-of-control surge because of holiday gatherings over the long weekend.Los Angeles County imposed a stay-at-home order for its 10 million residents, and Santa Clara County, in the heart of Silicon Valley, banned high school, college and professional sports and decreed a quarantine for those who have traveled more than 150 miles outside the county.In Hawaii, the mayor of Hawaii County said trans-Pacific travelers arriving without a negative COVID-19 test must quarantine for 14 days, and even those who have tested virus-free may be randomly selected for another test upon.