Food allergy in Singapore: opening a new chapter

Abstract

R ev iew A r tic le 244 I NTRO D U C TIO NSingapore has rapidly evolved into a modernised city state and currently faces the health burden of noncommunicable diseases (NCDs), resembling that of developed Western nations.(1) In children, allergic diseases, including food allergy, are among the most common NCDs.(2) Food allergy rates are reported to be more than 10% in challenge-proven studies among Australian infants, (3) while in the United Kingdom (UK) (4) and the United States of America (USA), Singapore have not met the expected rise experienced by other highly industrialised countries, it is also uncertain whether the food allergy epidemic will hit our nation. This unclear prediction, together with ever-changing cultural practices and eating habits due to immigration and overseas influence, has opened a new chapter of food allergy in Singapore.A PubMed search of the terms "food allergy" and "Singapore" generated a total of 45 results from January 1999 to January 2014. All the articles generated are in English. Of these, 12 articles are not food-allergy focused, and two are focused on food testing methodology that is not unique to Singapore. Of the remaining 31 articles found, 16 are studies conducted on children, and 9 are review articles on food allergy in Asia or Singapore. EPID EM IO LO GYIn Asia, food allergy data is just beginning to emerge, providing no satisfactory trend. One study from Chongqing, China, reported a doubling in the challenge-proven prevalence rates from 3.5% to 7.7% among 0-2-year-olds over a ten-year period. (8) Conversely, a South Korean study reported that the prevalence of food allergy symptoms in 6-12-year-olds had decreased from 10.9% to 8.9% over five years.(9) Preliminary findings in an ongoing study of young Singaporean children aged 11-30 months demonstrated that overall, self-reported food allergy prevalence could be as high as 5.4% (Lee AJ, unpublished). Unfortunately, the only prior data for comparison was in 6-12-year-olds, where the rates (also by questionnaire) were estimated to be 4%-5% in 1999.Given that the prevalence of food allergy tends to decrease with age, using this data, we surmise that food allergy has probably not increased in Singapore over a 14-year period. SPECIFIC FOOD ALLERGIES IN SINGAPOREWorldwide and regional differences in food allergies mainly depend on diet and culture (although this may not always be the case). For example, shellfish is the most common food allergen in Singapore and is ubiquitous in Southeast Asia, likely by virtue of its high consumption. However, fish, also eaten abundantly in Singapore, is a rare allergen here. Allergy to egg and cow's milk, despite their high consumption worldwide, is comparatively lower in Singapore than in the West. The reverse is true of peanut allergy, which is epidemic in the West compared to Asia. However, the pattern of food allergy in Singapore appears to have changed over the last decade, with peanut allergy increasing in prevalence and being the most common cause of anaphylaxis in Singaporean childr...

An Adjuvant-Free Mouse Model of Transdermal Sensitization and Oral Elicitation of Anaphylaxis to Shellfish

“…SF-specific IgG1, IgG2a, IgE and tIgE ELISAs were optimized, using the general ELISA-based method described by us previously [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,29]. For the plasma tIgE measurement, ELISA plates were coated with a capture anti-mouse IgE antibody per the supplier's protocol (BD Pharmingen).…”

“…Of the major allergenic foods, shellfish (SF), fish, peanuts and tree nuts are more likely to trigger life-threatening systemic anaphylactic reactions [1,2,3,4,5,6]. Furthermore, these 4 types of food allergy have also been identified as persistent, i.e.…”

“…Furthermore, these 4 types of food allergy have also been identified as persistent, i.e. where individuals sensitized to these foods rarely outgrow their clinical reactivity [1,2,3,4,5,6]. The prevalence of SF allergy has risen to significant levels in many westernized countries including the USA (1.3% among children and up to 2% among adults) [7,8], Europe (0.6%) and Canada (1.6%) [9,10].…”

“…SF allergy is a very common food allergy in Western countries, but appears to also have become more prevalent among both children and adults in parts of Asia. For example, in Singapore and the Philippines, the reported prevalence among teenagers is as high as 5.2% [4,11,12]. It is also a significant problem for people working in the seafood industry [1,2,3,4,5,6].…”

“…In mouse models, TDE to hazelnut, milk, cashew nut and sesame seed proteins (without adjuvant) can clinically sensitize mice for anaphylaxis [17,18,19,20,21,22,23]. Although TDE to SF protein is possible for people who work in the seafood industry, it is unclear whether clinically relevant sensitization can occur via this route [2,3,4,5,6,11]. …”