Interesting about the side effects. I found this:
Does the flu vaccine give you the flu?
Contrary to popular belief, all experts argue that you cannot get the flu from the flu vaccine because it contains no 'live' virus just the molecules that prime the body's immune system to fight off the potential virus.
Despite that, many people complain of feeling unwell afterwards. There are many possible reasons for this.
The NHS leaflet on flu immunisation warns that "some people may experience mild flu-like symptoms for up to 48 hours after immunisation as their immune system responds to the vaccine, but this is not flu".
And side-effects stipulated by the vaccine manufacturers include a sore arm at the site of injection, headache, fatigue, sweating, a slight temperature, pins and needles, shivering and aching muscles.
Read more:
http://www.dailymail.co.uk/health/article-367978/Do-need-flu-jab.html#ixzz0Wjzs6XNk