What is this mystery flu all about? Doctors call it severe acute respiratory syndrome, or sars, a highly contagious form of pneumonia, which originated in China last November. If you are travelling to Hong Kong, Singapore, Taiwan, Thailand and Vietnam, places where new cases have emerged, be careful and remember to wear a surgical mask in crowded places.According to the who, the symptoms include: fever higher than 100.4 F, cough, shortness of breath and breathing difficulty. The flu has no known cause or treatment. So far, commonly prescribed anti-viral drugs and antibiotics have proven ineffective. Docs in Frankfurt and Hong Kong claimed to have cracked the virus that is causing the killer flu: it resembles a paramyxovirus, the family of microbes that causes measles, mumps and canine distemper.