Tamiflu needs to be taken at start of flu. You don't wait around and assess whether or not you think it might be "fatal." The side effect of Tamiflu don't happen to everyone and can be reduced by taking the med with food.
BTW, the flu death statistics are WAY overrated. Only about 700 or so people die in the us from it every year. You can look on the CDC's own website and see that. The "36,000 dead" statistics are just hype to sell the flu vaccine, which will cause so many problems on its own. Gotta keep the pharmaceutical business thriving one way or another, ya know.
not everyone gets sick like that with the flu. It's been a long time since I've had it, but I never threw up with it.
As for death statistics.. I don't know about the 700.. but most of the people that do die from the flu are elderly, the young, or those with compromised immune systems. Outside of that group it is rare.