The last such shift that became an epidemic was the Hong Kong flu of 1968-1969, in which 34,000 Americans died instead of the usual 20,000 or so. This new flu has been verified to be a bonafide shift. But that's been the ONLY major cause for worry. Consider factor two. There is no evidence that this strain is highly contagious.
Nobody is known to have passed it to a family member.
Further, remember, Hong Kong is one of the most crowded places on earth. Since few Americans come into contact with living Chinese fowl, this is quite good news for us. Finally, there is the issue of deadliness. Horrible stuff, not to mention a slur on Spain since the first recorded cases were in the United States. But the yellow journalists appear to be out of luck this time.