The Huffington Post states there are 3 Sure-Fire Ways to prevent the swine flu (or H1N1)
Hygiene, Chiropractic, and Masks.
The media has not done a great job of covering the immunoprotective benefits of chiropractic care despite the research.
The Huffington Post states:
2. Chiropractic– One of the most important studies was performed by Ronald Pero, Ph.D., chief of cancer prevention research at New York’s Preventive Medicine Institute and professor of medicine at New York University. It showed the positive effect that chiropractic care can have on the immune system and general health.
Dr. Pero measured the immune systems of people under chiropractic care as compared to those in the general population and those with cancer and other serious diseases. His initial three-year study was of 107 individuals who had been under chiropractic care for five years or more. The chiropractic patients were found to have a 200% greater immune competence than those people who had not received chiropractic care, and they had 400% greater immune competence than those people with cancer and other serious diseases. The immune system superiority of those under chiropractic care did not appear to diminish with age. Dr. Pero stated:
When applied in a clinical framework, I have never seen a group other than this chiropractic group to experience a 200% increase over the normal patients. This is why it is so dramatically important. We have never seen such a positive improvement in a group. 
Another study from Patricia Brennan, Ph.D., leading a team of researchers, conducted a study that found improved immune response in her test subjects following chiropractic treatment. The study specifically demonstrated the “phagocytic respiratory burst of polymorphonuclear neutrophils (PMN) and monocytes were enhanced in adults that had been adjusted by chiropractors.” 
Life Chiropractic University produced an incredible study from the Sid Williams Research Center in 1994. The researchers took a group of HIV positive patients and adjusted them over a six-month period. What they found was that the “patients that were adjusted had a forty-eight percent (48%) increase in the number CD4 cells (an important immune system component).” These measurements were taken at the patients’ independent medical center, where they were under medical supervision for the condition. The control group (the patients that were not adjusted) did not demonstrate this dramatic increase in immune function, but actually experienced a 7.96% decrease in CD4 cell counts over the same period. 
The immune system is affected by the nerve system through the connections with the endocrine and the autonomic nervous system. And chiropractic care improves the function of the nerve system through improving the movement of the spinal bones that encase and protect the spinal cord.
Stressful conditions lead to altered measures of immune function, and altered susceptibility to a variety of diseases. Many stimuli, which primarily act on the central nervous system, can profoundly alter immune responses. The two routes available to the central nervous system are neuro-endocrine channels and autonomic nerve channels. 
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