2004-19 the flu vaccine was never more than 60% effective and in two years it was less than 20%. Science is shooting at a moving target. It could mutate into a more benign virus or a more aggressive virus next year. And it will mutate. What's promising is in two months of investigation with actual samples (China did not share very well in December and January) our scientist have identified the virus and are working on multiple vaccines to test. For those of us who remember the polio summers in the early 50's, this is reminiscent. But as a point of reference polio virus was identified in 1908 and a safe vaccine was on the market in 1955.