CHAPTER ONE
INTRODUCTION
1.1 Background of the Study
An allergy is a condition in which the immune system reacts abnormally, to a foreign substance. It is true that some animals producemainly more allergens than others, (Soukand et al, 2013).
When allergic reaction is triggered, to protect the body from this perceived threat or allergen, the immune system produces antibodies called immunoglobin E. IgE antibody are found mostly in the lungs, skin, and mucus membranes. They cause mast cells to release chemicals, into the blood stream. This property of IgE is unique to each allergen (Novo et al, 2013) An allergen specific immunoglobin E (IgE) blood test is done o check if there is an allergy to a particular substance. With the recent incident of zoo noses by household rats, to the extent of causing death in human populations, the importance of eradication rats from our environs cannot be over emphasized.