Methods: Observations were made after through study amongst,
- Population living in agricultural farm lands,
- Population from small city,
- 30 infants and children from small city visiting the village farmlands during last 18 years,
- Study of allergy in people migrating to USA for employment and their children born and brought up at USA.
- Comparative study of incidence of allergy from available resources world wide.
Results: In this multicentric study it was observed that the incidence of allergy amongst population related agriculture and farmlands to be 2 %, amongst people from small city to be around 4 % (1995 – 96), all the infants and children getting exposure to farmlands never showed signs of allergy, amongst children born to USA migrants who were born and brought up at USA most of them developed allergy symptoms. thus the population which was exposed to natural immunotherapy acquired better immune tolerance.
Conclusions: Natural immunotherapy done by exposure to allergens develops natural immunotolerance and avoidance of exposure is a disaster for future generations.