its really simple, ive had the test flu when I was younger, cold chills, head, runny noce the whole kabang, all you really need for prevention of the test flu is a GOOD multi-vitamin. it should be taken on a daily basis. I do have a few freinds who use test as well and ive had a few of them come to me and say the got the test flu, I asked them if they had been taken their vitamins and theyre reply was no. for the ones who haver taken their vitamins they never got it. Plain and simple we all should be taking a good multi-vitamin anyways. anyone who has done their research would no that test increases the amount of red blood cells in your body and anytime you have that increase to where your white blood cell stay the same you are going to be more prone to illness thats the main reason why we take vitamins to boost up our white blood cell count.