Hygiene Hypothesis: Exposure To Allergens In Early Life

INTRODUCTION

Hygiene hypothesis states that exposure to allergens in the environment in early life reduces the risk of developing allergies by boosting the immune system activities.1 Therefore individuals exposed to clean environments in their early life turn the immune system towards allergy promoting responses. This is referred to as the hygiene theory.1 Our body have been destroyed by an accelerated reduction in number and variety of microorganisms that populate our bodies and immediate environment which is the ecosystem for the microorganisms.

Hygiene hypothesis proposes that there is an increase in prevalence of chronic inflammatory disorders in developed countries as a result of decreased exposure to microbial environment which has modified

Hence, cleaner environments has brought about a situation where the body is not exposed to these infections and leading to attacks on grass pollen, dog hair and other irritants by the immune system which predisposes one to allergies.

These immunological basis include;

Effects of IgE

IgE is the main type of antibody involved in acting against parasitic infections. It is also the primary mediator of allergy symptoms.

IgE targets organisms that are large such as, helminths. This usually leads to huge inflammatory response at the site of contact with the microorganisms. This will usually produce different symptoms depending on the site of action. For example if it was in the eye, you will get itchy which leads to watery eyes.

Th2 (T Helper Cells 2) Response

The bacterial and parasitic immune systems have pathways which differ. The Th1 response is the bacterial pathway, while the Th2 response is the parasitic pathway. Both are based on the types of immune cell (T cell) that is