In 2005 a paper came out that showed the flu shot becomes less effective the more you get it, and in the elderly, increases, not decreases the risk of death. 
In 2012 Canada, noticing the US had no way to measure flu deaths, instead they estimated so Canadians invented a way (by counting flu deaths) and got some big award for it.  On a personal note my ex wife, Tressa Kirby, died of flu in 2011, the coroner's report said H1Na Flu, yet she was not among those counted. Our country reported zero H1N1 flu deaths that year. So I'm not sure if records haven't been updated yet or the system is less than perfect. Any system involving humans is subject to 20% error on average, these things happen - rjs)
The 2015 flu shot was mismatched and didn't offer any protection. The 2016 shot was matched and even offered less. At this point our health people had begun to give up on it.
By the US government own tests, even a small dose of vitamin C worked better . Tamiflu works less well (Cheney's company convinced governments worldwide to stockpile it. Ooops) 
The Atlantic had an article on it in 2009 , the CBC covered all the major details over the years. If you think all doctors suggest the shot you'd be wrong. Dead wrong. Many have been complaining about it for a while.
Note that I am personally not anti-vax. I vaccinated all four od my kids and myself and If I was gong to a place with Yellow Fever I'd get the shot for it. But I have only had maybe 2 flu shots at best over all these years. The ones that are safe and effective are good things. The flu shot is neither though I'm afraid. Not by the numbers, anyway, now that we have accurate ones finally.
A blanket condemnation (or promotion!) of vaccines is inappropriate, as is the insistence of a mono-culture of it. The myth there is nothing we can do about viruses was debunked just after WWII and the decisions made can be shown to have based on politics not not science. 
The H1N1 flu went through here in 09/10. I did as these vitamin guys suggest and was only sick for two days with it then back to work. Either that or I experienced spontaneous remission. it doesn't matter what you call it - ignore labels and examine th evidence.
My mum and youngest daughter went downhill for two weeks and when given a choice of emerg or vitamins, were suddenly better the next day in both cases when they chose the latter. The ex, stubborn little thing she was died of it after going downhill for 6 weeks; the coroner's report said H1N1. That's a lot of coincidental spontaneous remission. But it is consistent with a plethora of other clinical reports over the past 75 years, citations in Medline given in Levy. 
So, until there is clinical evidence the shot works and no longer increases the risk of death, there is no reason to get one and every reason to take vitamins instead. In short: C, B1, B3, D. Brazil nuts help because of the selenium, they're cheaper than pills.
Nobody died of flu with ascorbate in their blood. It's a medical impossibility. Just that one drug alone has brought people back from the brink of death from flu. Imagine how that could change people's lives.
"That's lower than we would like to see, but it's an improvement over the previous year, because it couldn't be worse, frankly"
Skowronski said the vaccine was well-matched, but overall, the protection was disappointing
'There's no use promoting a vaccine that isn't working well.' - Dr. Danuta Skowronski, BC Centre for Disease Control
 "Klenner's paper (Klenner FR. The treatment of poliomyelitis and other virus diseases with vitamin C. J. South. Med. and Surg., 111:210-214, 1949.) on curing 60 cases of polio in the epidemic of 1948 should have changed the way infectious diseases were treated but it did not." - Robert Cathcart
2010 Osterholm: Flu shot less than 60% effective, most vaccines are 90%
2018 Rice: Study predicts 2018 flu vaccine will likely have 20 percent efficacy
2019 AP: Flu shot protection drops from 47% to 9% in 2019 - A shot that didn't even work half the time dropped to 1 in 10 by end of season.
2019 CDC: Methodology
2019 NBC: Vaccine no match against flu bug that popped up near end
2019 UMN: Poor late-season protection limited flu vaccine impact for 2018-19
2019 WebMD: Last Flu Season's Vaccine Only 29% Effective: CDC
avian: Here is why it is a big deal that the flu shot does not work.
business: How vaccines became big business
chcs: Practitioners are paid for each flu shot they administer
ChildAndMom2019: "The flu shot this year also has little protection"
imm: More data
market: Global vaccine market revenues from 2014 to 2020