The labs almost never get the flu vaccine right because by the time they make it the flu has mutated. Last year the vaccine gave you a 45% protection. We have oil of oregano and elderberry tincture that we take during flu season. So far so good.
We stopped taking the flu shots years ago. I have been making the elderberry tincture instead.
We start taking a very small prophylactic dose (about a teaspoon) every day starting in November. We haven't gotten the flu in years and very seldom get a cold. If we start getting symptoms we immediately up the dosage to the "illness dosage" and it always seems to knock out what ever we were getting.
Elderberry tincture is great stuff. It is easy to make although you can buy it over the counter in Sambucol. But it is much cheaper to make it yourself and it keeps for years.