State of World Allergy Report 2008: Allergy and Chronic Respiratory Diseases

Increasing Prevalence

Asia is the world's most populous continent, with a population of almost 4 billion people and many emerging economies. According to recent epidemiological data from ISAAC phase III, asthma and allergic rhinitis have increased in several areas, mostly in low-and middle-income countries.^7,8 The prevalence of allergic diseases in Asia varies widely but was found to have increased (from 0.8% to 29.1% for asthma and from 5% to 45% for allergic rhinitis) as communities adopted modern lifestyles and became urbanized.

Time trends in the prevalence of asthma symptoms also showed different regional patterns, that is, a decrease in current wheezing in children aged 13 to 14 years in western Europe and an increase in wheezing children of the same age group in the Asia-Pacific region. Even within the Asian region, there was a wide variation among countries. The prevalence of asthma in Japan increased from 3.5% in 1982 to 4.6% in 1992⁹ to 9.1% in 2006 (A. Akasawa, M.D., Ph.D., unpublished data, 2006) and was accompanied by an increase in allergic rhinitis of up to 32% (A. Akasawa, M.D., Ph.D., unpublished data, 2006). Similarly, 2 surveys performed in Taiwan using an identical method showed that the prevalence of childhood asthma had increased from 1.3% in 1974 to 5.07% in 1985.¹⁰ More recent ISAAC III data showed that in 13-and 15-yearold children in Taiwan, the overall cumulative and 12-month prevalences of wheezing and rhinitis in the younger children were 8.2% and 44.4%, respectively, and those in the older children were 6.9% and 42.2%, respectively.¹¹ The percentage of children in Singapore who had experienced asthma at least once increased from 5.5% in 1967 to 13.7% in 1987 and to 20.7% in 1996. In Singaporean preschoolers aged 4 to 6 years, the cumulative and previous 12-month prevalences of wheezing were 27.5% and 16.0%, respectively. Asthma was reported by 11.7% of this group of children, and the current prevalence of rhinitis was 25.3%.

A field study conducted in four major cities in India with the use of a validated questionnaire showed the overall prevalence of asthma in 2006 to be 2.38%.¹² In a recent study in rural Bangladesh, the prevalence of asthma in children was 16.1%.¹³ In contrast, in nonrural Lhasa, Tibet, the prevalences of current wheezing and diagnosed asthma were 0.8% and 1.1%, respectively.¹⁴ The prevalence of allergic rhinoconjunctivitis in Tibet was 5.2%. Even within the same country, the prevalence of asthma differed among various populations.^7,8 Although overall regional data for adults are scant, between 1% and 10% of adults are estimated to have asthma, and between 10% and 32% are estimated to have allergic rhinitis.

Triggers And Risk Factors

Aeroallergens that trigger allergy and asthma vary from area to area in geographically diverse Asia. Although house-dust mites are the major triggering allergen in most of Asia, pollens, such as Japanese cedar pollen, are a major cause of allergic rhinitis in Japan. In a study of the prevalence of allergen sensitization among asthma patients in Thailand, house-dust mites (both Dermatophagoides species and Blomia tropicalis) were the most common sensitizing allergens in both pediatric and adult patients with asthma.¹⁵ Other important allergens, in order of priority, were cockroach and oil palm pollen. In contrast, less than 5% of patients were sensitive to other pollens and spores. Similarly, in a study of the sensitization profile of the general population in Southeast Asia to house-dust mites, subjects with rhinitis were most sensitive to B. tropicalis, followed by Dermatophagoides pteronyssinus (73% and 50%, respectively).¹⁶ Dual sensitization was common.

Although genetic factors are important in the manifestation of asthma and allergic rhinitis, the rapid increase in the prevalence of these disorders cannot be attributed to genetic factors alone. Changes in environmental factors also need to be taken into account. In a survey that compared the prevalence of asthma and atopic disorders in Chinese children aged 12 to 18 years in three Asian cities (Hong Kong, Kota Kinabalu, and San Bu, with Hong Kong being the most developed and westernized city), the prevalence of asthma and allergic disorders in children from Hong Kong was 2 to 6 times that in children from the other 2 cities.¹⁷ Allergic sensitization was a significant factor associated with asthma. The prevalence of atopy in Kota Kinabalu was high (64%), yet the prevalence of asthma was low (1.9%). In a cross-sectional prevalence analysis of wheezing, rhinitis, and eczema in Singaporean preschoolers aged 4 to 6 years, the main risk factors for current wheezing and self-reported asthma were family history of allergy, concurrent rhinoconjunctivitis, concurrent chronic flexural rash, and previous respiratory tract infection.¹⁸ In rural Bangladesh, risk factors associated with wheezing were pneumonia (at ages 0 to 12 months and 13 to 24 months), maternal asthma, paternal asthma, and maternal eczema.¹³

Despite extensive research on genetic, environmental, and lifestyle causes of asthma and on asthma risk factors--including pollution, tobacco smoke, diet, urban lifestyle, reduced early exposure to infections, and viral infections--no single factor has been identified as responsible for the marked geographic variation in or the increasing prevalence of asthma.

Morbidity and Mortality

Patients with asthma and allergic rhinitis have a reduced quality of life, and the burden of asthma, as assessed by disability-adjusted life-years, ranks 22nd among all diseases worldwide.¹⁹ Moreover, asthma in infancy often goes unrecognized and thus untreated.

The Asthma Insights and Reality in Asia-Pacific Study, which looked at patient perceptions of asthma management across Asia, concluded that patients experience frequent and unnecessary symptoms and exacerbations because of a lack of adequate asthma control.²⁰ Indeed, 27% of adults and 37% of children with asthma in the Asia-Pacific region reported that this condition had resulted in an absence from school or work in the previous year, and 40% reported being hospitalized, visiting the emergency department or making unscheduled emergency visits to other health care facilities in the previous year. The severity of asthma varied, with Vietnam and China reporting the most patients with severe persistent symptoms. Work absence was highest in the Philippines (46.6%) and lowest in South Korea (7.5%). In another survey of parents of children with asthma from four Asian countries, most of the children (73%) had preexisting symptoms of allergic rhinitis at the time when asthma was diagnosed, and comorbid asthma and allergic rhinitis substantially affected quality of life and worsened asthma symptoms.²¹

Mortality associated with asthma varies from country to country and seems to be high in countries where access to essential drugs is low. The Global Initiative on Asthma estimates that approximately 250,000 persons die of asthma annually, and the death rate per 100,000 persons with asthma aged 5 to 34 years in highly populated China is greater than 10%.²² However, asthma can be controlled with optimal treatment. This has been proven in countries where an asthma management plan was implemented and the morbidity rate subsequently decreased.²³

Socioeconomic Burden

The annual costs of treating asthma and allergic rhinitis--both direct costs (hospitalization, medications) and indirect costs (time lost from work, premature death)--are substantial and represent an even heavier burden in societies with emerging economies. The Asthma Insights and Reality in Asia-Pacific survey of urban centers in eight countries in the Asia-Pacific region showed that the annual per-patient direct costs ranged from US $108 in Malaysia to US $1010 in Hong Kong.²⁴ Total per-patient costs, including productivity costs, ranged from US $184 in Vietnam to US $1189 in Hong Kong. Urgent care costs were 18% to 90% of the total per-patient direct costs. The economic burden in the Asia-Pacific region was higher than that in the United States in relation to the per capita gross domestic product (13% in the Asia-Pacific region compared with 2% in the United States) and per capita health care spending (300% in the Asia-Pacific region compared with 12% in the United States).^24,25 Approximately US $20 billion are spent globally each year in relation to allergic rhinitis--a figure that includes the costs associated with medications, lost work productivity, and physician consultations. Approximately US $3 billion are spent in Japan alone.

Working Group on Health Promotion and Prevention of Chronic Respiratory Disease and Allergies

Everyone has the right to live and work in a clean environment. Exposure to an unhealthy environment can cause severe and debilitating chronic obstructive pulmonary disease, asthma, cardiovascular diseases, and cancer. Complete elimination of risk factors is the only way to remove the risk, and this strategy applies equally to tobacco smoke, indoor and outdoor air pollutants, occupational hazards, and allergens. This working group will encourage countries to implement policies to reduce the burden of tobacco smoke, indoor and outdoor pollution, occupational hazards and other risk factors relevant to chronic respiratory disease.

Working Group on Diagnosis of Chronic Respiratory Disease and Allergies

The first initiative for the Diagnostics Working Group is to survey WAO Member Societies (national and regional allergy and clinical immunology societies worldwide) to define the most relevant allergens in each country. This will enable the group to ensure the development of low-cost tests for immunoglobulin E sensitization against the most common respiratory and food allergens in any country or region. A second survey was created to obtain information about which in vivo and in vitro tests are most commonly used worldwide to detect respiratory, food, and drug allergies.

The Diagnostics Working Group will also conduct allergy skin prick tests for immunoglobulin E sensitization using either standardized manufactured allergens (in high-and middle-income countries) or locally produced reliable extracts (in middle- and low-income countries). Central to this is the detection of relevant regional allergens, done in cooperation with the WAO Emerging Societies Program (see Developing the Specialty of Allergy Worldwide), which has placed pollen traps in countries where major airborne allergens need to be identified.

Working Group on Control of Chronic Respiratory Disease and Allergies

The GARD action plans should be tailored to each country's needs, priorities, health services, and resources.

Working Group on Pediatric Chronic Respiratory Disease and Allergies

Approximately 70% to 80% of asthma in children is allergic in origin, and 5% to 15% of the global pediatric population is thought to have asthma.⁴ The Pediatrics Working Group believes that future increases in asthma prevalence will likely be greatest in the developing world. The group has outlined objectives for the diagnosis and management of pediatric asthma in high-, middle-, and low-income countries. The priorities are to develop an asthma-symptom algorithm to aid health care practitioners in making diagnoses and to provide "Is it asthma?" symptom cards, developed by GARD, to facilitate such diagnoses. Pamphlets and posters will also be developed to increase awareness about asthma. Emphasis will continue to be placed on the importance of avoiding tobacco smoke. Finally, prevalence studies will be conducted in preschool children.

The WAO Emerging Societies Program

The WAO Emerging Societies Program encourages the development of new national allergy societies throughout the world, particularly in low-income countries. The program is provided in collaboration with the American College of Allergy, Asthma, and Immunology. While enabling the sharing of practical experiences and alerting aspiring societies to the criteria required for WAO membership, the program helps to create local support networks for allergists through partnerships with established allergy societies within the same region and fosters a relationship with WAO. At the same time, the WAO leadership learns about the challenges and opportunities faced by colleagues in developing countries. Membership in WAO enables fledgling societies to become a part of the global allergy community and to have a voice in WAO's House of Delegates, where the societies can help to determine the organization's future activities.

The WAO is planning a network of local summer schools that will provide hands-on training in allergy diagnostic techniques and methods of treatment delivery in areas where allergy services are newly established. In 2008, the Emerging Societies Program will hold a summer school for primary care physicians in Latin America, an area where allergy services are deficient. The summer school will provide training in the fundamentals of allergy diagnosis and treatment.

The Emerging Societies Program has loaned pollen traps to centers in Pakistan, Ukraine, and Georgia. These traps are helping allergists identify the major local airborne pollens and molds responsible for allergic respiratory diseases in these countries, and the hope is that the information acquired will eventually lead to the availability of appropriately directed diagnostic materials and immunotherapy vaccines. The distribution of more pollen traps is an urgent priority.

Allergy Learning and Educational Programs

The WAO offers a variety of educational and learning programs that reflect the diversity of learning needs within the global allergy environment. The Global Resources in Allergy (GLORIA) program provides educational materials in the form of didactic lectures on major topics in allergy; these lectures are available on the WAO Web site so that the organization's 35,000 members can use the GLORIA materials in teaching programs.¹⁰ The Seminars and Conferences Program provides invited lecturers to speak at member societies' meetings on topics selected to specifically meet the learning needs of the societies' local clinical and scientific allergy community. In 2007, WAO provided lectures on various aspects of allergy to more than 25 allergy and clinical immunology societies throughout the world and will provide even more in 2008.

To further improve education worldwide, WAO has just created an online clinical journal, The World Allergy Organization Journal, to be a major academic resource for the world's allergy community.¹¹

Focusing on the knowledge objectives for physicians as defined by the Specialty and Training Council,⁸ WAO is also developing learning programs aimed at meeting the learning needs of the diverse range of physicians who care for patients with allergic diseases. A major strategy of this goal is online education, which is increasingly accessible worldwide and is a cost-effective way of providing learning and educational materials asynchronously at a convenient time for global users. New initiatives for 2008 include a series of 11 online lectures on the basic immunology underlying allergic disease and a series of online learning programs based on complex clinical case histories, through which users are guided through the wealth of educational materials that are available on the WAO Web site.

Promoting Allergy Research

The WAO Research Council awards annual short- and long-term research fellowships enabling junior clinicians to visit an international expert center to learn a clinical or scientific technique that is not available at the home institution or to participate in a research study. These programs aim to help the students' home institutions establish new research programs, and particular emphasis is given to encouraging research in low-income countries. Fellowships are directed toward three broad research priorities:

Best-Practice Recommendations and Position Statements

The WAO collaborated with the WHO to develop recommendations for the prevention of allergy and allergic asthma based on the recommendations of a group of international allergy experts representing all WHO regions. The document, published in 2004, summarized current knowledge on the prevention of allergy and allergy-related asthma and made recommendations for future research to address knowledge gaps.⁴

The WAO Research Council oversees the creation of position statements on major topics in allergy. "Recommendations for Standardization of Clinical Trials With Allergen Specific Immunotherapy for Respiratory Allergy: A Statement of a World Allergy Organization Taskforce" was published in 2007 to ensure that new clinical trials on allergen immunotherapy are conducted in a standardized way that will enable worldwide comparability of results.¹²

The WAO is conducting studies on the current availability of epinephrine and on the local management of anaphylaxis in all member society countries. In parallel with these studies, the organization is developing global recommendations on the use of epinephrine for the treatment of anaphylaxis. Although epinephrine is the drug of choice for the treatment of anaphylaxis, this drug is not yet globally available. The hope is that WAO initiatives will assist national societies in persuading health care funding bodies of the importance of making epinephrine widely available for the treatment of anaphylaxis.

Communication

The WAO Web site (http://www.worldallergy.org) is a major tool for disseminating education and information. A monthly e-newsletter reaches more than 26,000 allergists and is available in eight languages. The newsletter provides reviews on current scientific literature and books, updates on WAO activities, and opportunities for member societies to apply for educational programs and fellowships. The WAO Web site contains extensive educational resources and contact information and provides links to all WAO member societies' Web sites and selected allergy resources on the World Wide Web.

World Allergy Day takes place every two years and is themed on activities at the biennial World Allergy Congress. This event provides an opportunity for wider dissemination of knowledge on major topics in allergic disease, with participating member societies, local media, and patient groups focusing on those aspects of allergic disease that have the greatest impact on local communities.

All WAO resources and services are designed to increase the knowledge and awareness of allergic disease and enhance the clinical practice of allergy. The WAO's role is to support member societies in promoting the specialty at a national level and to provide information to help in negotiations to obtain optimal resources for the care of allergy patients. Thus, development of the specialty of allergy, physician education and information, best-practice recommendations, promotion of allergy research, and creation of an awareness of the global allergy burden are critical responsibilities of WAO. Because of the enormous global burden of allergic disease, most patients with allergy will not be seen by an allergist; therefore, non-allergists must be educated to recognize, diagnose, and treat patients with uncomplicated allergy and to know when and how to refer patients with complex disease to an allergist.

Climate Change

Recently, much attention has focused on climate change and the impact of climate on allergy. Experts from the World Health Organization discussed the impact of climate on allergy in May 2007, and numerous articles on this topic have appeared in the literature and on the Internet.^1-19 Climate affects many aspects of allergy and allergen exposure, including the type and frequency of allergens in any particular geographic location, exposure to food and insect allergens, cross-reactivity among allergens, and the prevalence of allergy-related diseases.

The world is in the initial stages of a global climate change that will alter flora and fauna everywhere, creating changes in the profile of local allergens and potentially lengthening pollen allergy seasons. As temperatures increase, plant species are moving into previously temperate regions and to higher elevations; similarly, when temperatures decrease, these same plant species may recede back to the original habitat, whereas other plant species that typically grow only in colder locales or at higher elevations may spread farther into previously warmer areas. As warm seasons lengthen, so will many plant pollination seasons; therefore, human exposure to allergenic pollens will increase. Increases in temperature will result in increases in humidity in many places, which in turn will provide a better environment for mold growth and an increase in the number of airborne mold spores. Increases in temperature in desert regions are reducing the amount of fertile land available for agriculture, which leads to the migration of large numbers of workers into urban areas. This rural to urban migration has already been shown to result in an increase in the number of patients with asthma and allergy symptoms. Changes in climate will affect crop patterns and increase the likelihood of new inhalant allergens being introduced into a locality. In addition, insect species will continue to migrate to new locations as temperatures increase. Allergies to stinging insects may increase as new insects are introduced into the environment, and the number of cockroaches and house-dust mites--and thus, the allergen load--will increase in accordance with increases in heat and humidity.

Cross-reactivity of allergens currently in the environment with new allergens that are introduced through plant and insect migration could result in the development of multiple immunoglobulin E (IgE) antibodies against these allergens. This in turn will cause patients to react to more allergens, increase the number of allergy patients, and lead to the development of more complex manifestations of allergic disease.

Although attempts to reduce pollution are gaining importance in some parts of the world, pollution is dramatically increasing in other developing areas. To confound this issue, measures aimed at reducing atmospheric pollution will likely result in a decrease in the number of patients with chronic respiratory diseases, such as bronchitis. However, in areas such as the former East Germany, the number of patients with allergy-related respiratory diseases reportedly increased as chronic respiratory diseases decreased.

Allergy has been called "the 21st century disease" because as people live cleaner, healthier, less infection-prone lives, allergies increase in frequency. A theory on how improved hygiene leads to a shift in immune responses favoring an allergic-type response has strong scientific support. Thus, as the world develops to a more industrialized less agriculturally based economy, allergies will continue to increase and plague those very areas where lifestyles are improving.

Dietary Changes Caused by Industrialization

Allergy clinicians are seeing an epidemic of food allergies in developed countries.^20,21 Up to 10% of children in the United States and Europe will develop food allergies during the first decade of life, with the highest incidence in the first one or two years of life. A reduction in breast-feeding by working mothers has led to an increase in exposure at an early age to foreign proteins such as those in cow's milk. Moreover, these bottle-fed babies are ingesting foreign proteins that would ordinarily be broken down by the mother's digestive and immune system during the formation of breast milk. Greater use of processed foods and preservatives may also increase the exposure to more allergenic proteins. Genetic modification of food can introduce an allergen into a previously "safe" food, rendering the food allergenic to those who are sensitized to the modifying protein.

Decreases in the Number of Trained Physicians for the Projected Increase in Allergy Patients

Estimates indicate that up to 20% to 25% of the population of every developed nation will develop some form of allergic disease.^22,23 As countries develop more comfortable lifestyles and life-threatening infections are eliminated, allergies not only will continue to increase, but will affect this increasing segment of the population for a lifetime and lead to increased losses in productivity both at school and in the workforce, and thereby result in greater costs to society. With further reductions in breast-feeding and increases in exposure to processed food, food allergies will become more serious and more widespread. Accurate diagnosis and treatment of IgE-mediated food allergy will become ever more important. As the Third World moves to the First World and as the prevalence of allergy increases globally, the need for more allergy practitioners and new allergy treatments will increase.

Clearly, there are not enough allergists to diagnose and treat the projected increased number of patients with allergy.²⁴ This shortage of appropriately trained health care providers is compounded by the fact that in many highly industrialized countries, the overall rising costs of health care have dictated a reduction in the specialty care provided by allergists, with the expectation that allergy can be treated adequately by family practitioners. Many patients with allergies are treated by physicians who have had an extremely limited exposure to allergy diagnosis and treatment during medical school and postgraduate training.

The WAO, speaking for all 77 allergy and immunology member societies worldwide, has just published two position statements addressing these issues: the first, "What Is an Allergist,"²⁵ defines the special clinical skill sets of a trained allergist; the second, "Requirements for Physician Competencies in Allergy: Key Clinical Competencies Appropriate for the Care of Patients With Allergic or Immunologic Diseases,"²⁶ delineates exactly what training is required for physicians at all levels to care competently for allergy patients. The WAO Specialty and Training Council is now developing a recommended training syllabus in Allergy and Clinical Immunology to provide a standardized basic curriculum that can be adapted for local use around the world. The hope is that the governing bodies of the world's medical communities will attend to these position statements and not only recognize the current and future deficiencies in the numbers of well-trained allergists, but also encourage specialty training in allergy diagnosis and treatment on a more local level. New WAO initiatives will address the importance of including allergy and clinical immunology in undergraduate medical training and of the special skill sets required for physicians treating children with allergic diseases.

Antihistamines

Oral antihistamines have traditionally been the first-line therapy for rhinoconjunctivitis and allergic skin conditions. Histamine is at least partly responsible for most or all of the primary symptoms of allergy, both in the mucosa of the nose and eyes and in the skin. Countless patients worldwide have benefited from the use of oral antihistamines, which reduce sneezing, itching, and rhinorrhea. In recent years, newer non-sedating antihistamines have become available and are recommended because these agents cause less sedation, have more selective mechanisms of action, and are longer lasting. Because oral antihistamines are accepted and are available worldwide, these drugs will likely remain the standard treatment of choice for allergic diseases, and the use of nonsedating antihistamines will likely increase. Nasal antihistamine sprays have also become available more recently and are very effective. In the future, both oral and nasal antihistamines will likely be used to treat rhinitis, and oral antihistamines will likely be used to treat cutaneous disorders.^27,28

Corticosteroids

Recognition that topical corticosteroids are the most effective treatments available for rhinitis and asthma should lead to an increase in the use of these drugs for the treatment of these diseases worldwide. Some of the mature corticosteroid products are very inexpensive; therefore, well-trained practitioners can prescribe these modern medicines even in regions where resources are limited.

The WAO anticipates that the emphasis will likely be to use more topical rather than systemic treatments for rhinitis and asthma. The combination of topical nasal corticosteroids and antihistamines actually potentiates the activity of each drug in the treatment of rhinitis, and such a combination product, once marketed as a dual-acting nasal spray, is likely be the preferred choice for treating both allergic and nonallergic rhinitis. Surgical treatment of sinusitis will inevitably become less popular as the understanding of this condition increases and effective treatments, including corticosteroids developed in vehicles that allow instillation within the sinuses, become more widely available.^29-31

Predictably, the medications currently used to treat allergy may not all be used in the future. Many modern medications are cost prohibitive and are therefore unavailable to much of the world. Future advances in pharmaceuticals may provide relatively inexpensive treatments, which will be particularly cost effective if used appropriately by both clinicians and patients.

Immunomodulation

Modulation of the immune system to decrease the production of IgE, and thereby reduce the incidence of allergic disease, should become a reality. In contrast, immunomodulation to increase the production of IgG might help prevent infectious diseases in patients with IgG deficiencies.

Allergen Immunotherapy

Allergen immunotherapy has become highly standardized as allergens have become characterized, which ensures an accurate diagnosis and treatment with the specific allergen to which patients are sensitized.^32,33 Comparative data indicate that allergen immunotherapy is a potent long-term treatment capable of reducing the severity of allergic rhinitis and asthma. Data indicate that the use of immunotherapy to treat children with allergic rhinitis reduces the subsequent development of asthma. Thus, allergen immunotherapy should be considered for the long-term management of appropriately selected allergic patients.

Traditionally, allergen immunotherapy has been administered via subcutaneous injection. Support for this preferred route of administration is based on 100 years of experience and the results of a multitude of studies on the use of high-dose subcutaneous injection therapy. An alternative form of immunotherapy is the sublingual administration of allergen, the effectiveness of which has been demonstrated in European patients with rhinitis caused by certain allergens, such as grass and house-dust mite. Sublingual immunotherapy has become the preferred treatment of some allergic patients in Europe. Studies examining the efficacy of this treatment in other populations are underway. Because sublingual immunotherapy is self-administered, a strong likelihood exists that this therapy will be preferred by patients once proven and approved throughout the world.

Immunotherapy is the only current treatment that has long-term benefits, that is, effects that last beyond the period of active treatment. Studies have clearly shown that effective allergen immunotherapy can have protective effects that last for years after treatment has ended. Thus, immunotherapy can reduce allergic rhinoconjunctivitis and asthma, can reduce the development of asthma in treated patients, can produce effects that last for years after the completion of a successful program, and may become available as sublingual drops for some patents. An increased use of immunotherapy in the future seems likely. However, well-trained practitioners are essential to ensure the accurate identification of the causative allergen or allergens, to determine when sublingual immunotherapy should be used, to ensure patient safety, and to select allergens that are appropriate to the patient.

Biotechnology

Monoclonal antibodies against IgE and the various cytokines and mediators involved in the allergic cascade are being extensively researched.^34-36 A humanized monoclonal antibody against IgE is already available for use in adults and adolescents with moderate to severe allergic asthma and may soon be indicated for use in children. Studies are underway to determine the full range of atopic conditions for which monoclonal anti-IgE therapy may be efficacious. Cost considerations and the availability of trained allergists to determine the patients for whom this type of therapy will be effective will initially determine the global availability of this class of treatments.

Epinephrine

Anaphylaxis is an acute life-threatening condition that affects about 1% of the population of most developed countries. More than 200 patients are estimated to die of anaphylaxis in the United States each year. Autoinjected epinephrine (adrenaline) is an extremely effective treatment of acute anaphylaxis because this drug reverses all of the life-threatening processes involved in a matter of minutes.^37,38 Practitioners in countries where this therapy is licensed can readily provide epinephrine-containing devices to patients at risk for anaphylaxis from stinging insects, food allergies, and other causes of anaphylaxis.

The fact that many countries still do not license epinephrine injectors for prescription purposes is amazing. The WAO's leadership believes that autoinjectors of epinephrine need to become more widely available and that physicians need to be instructed in how and when to use these injectors for the treatment of anaphylaxis. In countries where epinephrine autoinjectors are available, anaphylaxis can be successfully managed by patients who are trained to use these devices correctly. However, epinephrine injectors should be prescribed only by practitioners with the knowledge to: accurately diagnose the symptoms of anaphylaxis, diagnose the causative allergens, advise patients on strategies to avoid the offending allergen, and train patients in the proper use of this life-saving treatment. Recognizing, even in 2007, that self-injectable epinephrine devices are still not available in many countries with huge populations, WAO will continue to campaign for the global availability of this essential therapy.