In Avoiding the Swine Flu, Dr. Michael Eades says:
This swine flu is a type A influenza, which is a type that can usually be warded off prophylactically with amantidine (Symmetrel), an inexpensive drug that is readily available. But from my reading, it looks like this particular strain of influenza A is resistant to that drug. There are a couple of other drugs that are effective in the treatment of this flu – Tamiflu and Relenza – but I wouldn’t use them as a prophylactic. Keep them in reserve in the unlikely event that you should actually contract this flu. …
As far as I’m concerned, the single best thing you can do is to make sure your vitamin D levels are where they are supposed to be. On days that I’m not in the sun, I always take a 5,000 IU vitamin D3 capsule. If I feel like I’m coming down with something or if I’m going on a long flight, I’ll take a 50,000 IU capsule.
In addition to the vitamin D, the other things you can do are as follows:
Eat plenty of good quality protein and fat. Your immune system is made of protein and fat, so eat what it needs.
Avoid sugar and refined carbohydrates. A number of scientific studies have shown that sugars and refined carbohydrates increase inflammation and, consequently, occupy much of the capacity of the immune system.
Get plenty of sleep. Sleep is a great immune enhancer. Remember all the times you’ve shorted yourself sleep and ended up catching a cold.
Wash your hands frequently and keep them away from your nose and eyes.