Dr. Graham Rook, an immunologist at University College, London, and one of the most enthusiastic proponents of the hygiene hypothesis, surmises that the immune system benefits from exposure to mycobacteria, a family of bacteria species that live primarily in soil and fresh water. Mycobacteria don't live in the human body, so grubbing around in the dirt is the best way to meet them. Most city kids don't see much soil, and what they do see outside is less than inviting. Just such a method was used in a recent study of Japanese kids, who had been given a tuberculosis vaccination consisting of a weakened form of T.B. mycobacteria. Results showed that they had a much lower rate of allergies and asthma.
Similar studies are underway regarding the treatment of asthma.
Rook is among the researchers conducting studies to see if inhaling or injecting mycobacteria can prevent asthma attacks. Preliminary results suggest that the immune system can be at least partly reprogrammed in adulthood. Professor Tony Basten, director of the Centenary Institute of Cancer Medicine and Cell Biology in Sydney, Australia, envisions a future vaccine, to be given to children with a family history of asthma, that would contain genes from dust mites. All rights reserved.