Role of Environment in Asthma, Endotoxin and other Factors

Asthma has a high prevalence and a chronic relapsing course. Childhood asthma is a global health problem that imposes a burden on family, health care and society as a whole, and results in a massive social and economic cost to the community. Many but not all cases of asthma are associated with features of allergy such as sensitization to food and inhalant allergens, allergic rhinoconjunctivitis and atopic dermatitis.
Rates of asthma and allergies are increasing with westernization, urbanization and affluence. For example, the prevalence of asthma and atopy among children living in Hong Kong is similar to European figures, whereas much lower rates have been found among children living in Beijing and Urumqui in mainland China. In rural China asthma is almost non existent with a prevalence of less than 1 percent.
Across Europe a north-south and west-east gradient in the prevalence of asthma and allergies has been demonstrated in large surveys enrolling children (ISAAC) and adults (ECRHS). Strong contrasts have, however, also been seen on a much lower spatial scale, i.e. among children raised on a farm as compared to their neighbors living in the same rural area but not on a farm […]