Actually there are lots of Eastern Medicine/Herbal drinks that develop resistance to flu. There are actually non-medicinal drinks that people can drink regularly like those exotic fruit drinks (but taste horrible) which at times even end up curing softer cases of flu. But healthy drinks won't feed the medical-industrial complex. There are too many types of flu and most of them are not even fatal. Fortunately in my country almost nobody gets flu shots. They just get some pills from the doctor and bed rest.
I personally don't even see the doc most of the time. I let my body naturally fight it and don't even take paracetamol most the time. Healthy immune system is what we need. Health is a lifestyle. You can't fix it with pills and shots.
I completely agree with you. I only took vaccines when I was 6(sadly),and now I barely go to the doctor(except when I need checkups, but I don't take any meds). I also drink at least a liter of water everyday! I used to get sick a lot about 2 years ago, but when I stopped eating meat and started eating healthy, not taking meds and dressing less(so I can handle more cold weather), now I am never sick!