Due to mild Asthma attacks a few years back, I got a flu vaccine for 5 consecutive years (2013-2018). But after around 8 months after my first shot in 2013, I was diagnosed with Major Depressive disorder. I learnt Depression is one of the side effects of Flu vaccine and coincidentally my Depression started right after a few months. I've been depressed since then and the condition is fluctuating and I've been trying many antidepressants with no or little improvement. Is it because of the flu vaccine? If yes, what can I do to treat my depression?