Food allergies in developing and emerging economies: need for comprehensive data on prevalence rates

Food allergy is the consequence of maladaptive immune responses to common and otherwise innocuous food antigens [1]. The most common allergenic foods are cow’s milk and dairy products, hen’s egg, peanuts, nuts, gluten containing cereals (e.g., wheat, rye, barley), sesame, soybeans, mustard, fish, crustaceans and shellfish [2-6]. These specific food substances are frequently referred to as “priority food allergens” as they account for over 90% of all food allergic reactions. Other less common allergenic foods include legumes, and some fruits and fruit juices (e.g., kiwifruit, apple, grape) and vegetables (e.g., celeriac, carrots, onions).Rising prevalence of food allergy and intolerance in the developed world has attracted much attention in the last two decades. Consequently, there is a growing body of knowledge about the prevalence, health and social impacts of food allergy in many developed countries. Work done by the Food Allergy Research and Resource Program (FARRP) and other institutions in the United States of America (USA) have allowed allergy prevalence rates in the country to be estimated at 3.5-4.0% [7,8]. A nationwide study in the USA specifically focusing on peanut and tree nut allergy reported 1% overall prevalence rate of allergy to these foods [9]. Various international initiatives such as the InformAll database and EuroPrevall, a European Union funded project which focused on the prevalence, cost and basis of food allergy in Europe have provided very useful data on prevalence rates across Europe [10,11]. Estimates of prevalence based on food challenge studies ranged from 0% to 3% for milk, 0% to 1.7% for egg and 1% to 10.8% for any food. In Canada, Ben-Shoshan et al.[12] reported probable prevalence rates of 0.9%, 1.1%, 0.5%, 1.4% and 0.1% to peanut, tree nut, fish, shellfish (specific type not specified) and sesame. Similar studies have been conducted in Australia and Japan [13]. Together, such studies have helped to raise awareness of food allergies