About 20% of the general population has an allergic diathesis or genetic predisposition to manifest with symptoms of allergic disease, most notably allergic rhinitis and conjunctivitis often accompanied by eczema or atopic dermatitis. This inherent propensity to develop the above clinical disorders remains the same regardless of whether the individual lives in a rural or urban environment.
As with most medical disorders, clinical or phenotypic expression can vary from the mildest to the most severe for obscure reasons. However, there is evidence supporting the relative benefit of a rural environment on the severity and outcome of allergic disease.
It has been reported in most industrialized countries that individuals who live in urban areas tend to become more greatly affected by allergic disease than those living in rural areas. A major factor is greater air pollution in urban areas which has been demonstrated to significantly increase the frequency and severity of allergic respiratory disease. Industrial pollutants such as ozone, nitrogen oxide and sulfur dioxide as well as road traffic gaseous particles and emissions have been demonstrated to have a bronchoconstrictor effect in the lungs.
In addition, air pollutants have the potential to damage the airways mucosal surfaces facilitating the penetration of allergens intensifying the disease process. A Mongolian study demonstrated a significantly higher sensitivity to pollen in urban as opposed to rural areas. This was supported by research investigators in African countries such as Ghana, Zimbabwe and South Africa.
Furthermore, in accordance with the hygiene hypothesis, it has been reported that allergic disease has a higher prevalence with improved hygiene in urbanized communities associated with less microbiological or infectious disease exposure.
The views expressed are solely those of the author, based on his knowledge and expertise and do not necessarily represent the views of the manufacturer.
If you think you are experiencing allergy symptoms, please consult your health care professional for a definitive diagnosis.