It brings much of China’s economy to a halt and strains transport systems, not to mention waistlines. Chinese New Year is an annual ritual of family reunification and overindulgence. The scale of the migration is astounding: While an estimated 116 million Americans were on the move around the Christmas and New Year’s holidays, Chinese citizens will rack up about 3 billion trips during this year’s travel-fest. A widening pneumonia outbreak that began in December has added some complications this