The prevalence of allergic diseases and asthma are increasing worldwide, particularly
in low and middle income countries. Moreover, the complexity and severity of allergic
diseases, including asthma, continue to increase especially in children and young
adults, who are bearing the greatest burden of these trends. In order to address this
major global challenge that threatens health and economies alike it is important to
have a global action plan that includes partnerships involving different stakeholders
from low-, middle-, and high-income countries.
Allergic diseases include life-threatening anaphylaxis, food allergies, certain forms
of asthma, rhinitis, conjunctivitis, angioedema, urticaria, eczema, eosinophilic disorders,
including eosinophilic esophagitis, and drug and insect allergies. Globally, 300 million
people suffer from asthma and about 200 to 250 million people suffer from food allergies
. One tenth of the population suffers from drug allergies and 400 million from
rhinitis . Moreover, allergic diseases commonly occur together in the same individual,
one disease with the other. This requires an integrated approach to diagnosis and
treatment and greater awareness of the underlying causes amongst family physicians,
patients as well as specialists
A report from the World Allergy Organization, the WAO White Book on Allergy (originally
published in 2011) and updated in 2013 summarizes the burden of allergic diseases
worldwide, the risk factors, impact on quality of life of patients, morbidity, mortality,
their socio-economic consequences, recommended treatment strategies, future therapies,
and the cost-benefit analyses of care services. It also offers “high level” recommendations
for action on allergy education for health care professions and enhanced patient service
provision. WAO is concerned about the rising global burden of allergic diseases and
is committed to increased cooperation at a global level engaging governments and policy
makers to channel resources and efforts to recognizing allergic diseases as a public
health issue. WAO has updated the original WAO Book on Allergy, in 2013 to contain
new information, providing the latest data, evidence, and treatments with a new chapter
on Severe Asthma, updated introduction and executive Summary and several updated chapters.
For instance, asthma prevalence is rising in several high as well as low and middle
income countries and the prevalence and impact of allergic diseases continue to grow.
According to the World Health Organization, the number of patients having asthma is
300 million and with the rising trends it is expected to increase to 400 million,
by 2025. Patients with asthma and allergic diseases have a reduced quality of life.
According to the World Health Organization asthma causes 250,000 deaths annually.
Moreover, asthma in infancy often goes unrecognized and thus untreated. In the United
States, 23 million people including 7 million children suffer from asthma and the
prevalence is increasing. The economic costs of asthma are high both in terms of direct
and indirect costs  (Table 1) especially in severe or uncontrolled asthma. In the
United States, pediatric asthma results in 14 million missed days of school each year,
which in turn result in lost workdays — and lost wages — for caregivers . As asthma
continues to affect more children in lower-income countries, this will lead long-term
consequences for their education and perpetuation of their poverty. We need to find
ways to control indoor and outdoor air pollution, to train health care professionals
to diagnose and treat asthma in children, and to ensure that asthma medications are
affordable for all who need them. Educational programs for self-management of asthma
and national efforts to tackle asthma as a public health problem have produced remarkable
benefits resulting in dramatic reductions in deaths and hospital admissions [1,3].
The economic burden of allergy
Year costs calculated
Total costs estimated
A$ 1.1 billion
A$ 8.3 billion
A$ 9.4 billion
Up tp US$ 9.7 billion
Up to $20.9 billion
A few global facts and figures for two common allergic diseases: asthma and rhinitis.
*Direct costs: Expenditure on medications and health care provision.
**Indirect costs: Cost to society from loss of work, social support, loss of taxation
income, home modifications, lower productivity at work, etc.
Extracted from Ref . Pawankar R et al.
The upsurge in the prevalence of allergies is observed as societies become more affluent
and urbanized. An increase in environmental risk factors like outdoor and indoor pollution
like tobacco smoke combined with reduced biodiversity also contributes to this rise
in prevalence. In many low- and middle-income countries including in rural areas in
India, people rely on solid fuel (wood, cow dung or crop residues) that they burn
in simple stoves or open fires for domestic energy . Secondhand smoke has become
more common as parents become affluent enough to buy cigarettes. Together, these factors
generate indoor air pollution that is estimated to be as much as 5 times as severe
in poor countries as in rich ones . In rural Bangladesh, the prevalence of wheezing
in rural children over a 12 month period was 16% . The White Book highlights data
from China that reports outdoor pollution as a cause of 300,000 deaths annually .
Moreover climate change, reduced biodiversity , change in ambient temperatures,
changes in weather during pollen seasons can cause both biological and chemical changes
to pollens and have direct adverse consequences on human health by inducing disease
exacerbations especially in urban and polluted regions. Appropriate environmental
control measures of risk factors like indoor tobacco smoke, outdoor pollution and
biomass fuel can have huge health benefits. There is also other complex but measurable
associations between early life circumstances like maternal and childhood nutrition.
Such evidences indicate early life opportunities for interventions targeted towards
the prevention of allergies and asthma.
Persons with allergic diseases like asthma also often have other comorbid conditions
like diabetes, obesity, cardio-vascular disease, gastro esophageal diseases leading
to more complex situations and worse outcomes associated with these complications.
Furthermore, owing to the high health care costs, morbidity, impact on quality of
like, absenteeism, poorer work performance and socio-economic costs, allergic diseases
result in a socio-economic burden to the affected families as well as countries. The
costs for treating rhinitis in the US have doubled in 5 years to 11 billion US$. In
the developed countries, the financial burden of asthma ranges from US$ 300 to 1300
per patient per year annually. In developing countries, like Vietnam it is estimated
to be US$184 per patient per year and in India, the monthly cost of medication for
an asthmatic child can amount to one third of an average family’s monthly income.
In the light of this ever-increasing threat of allergic diseases, high-, middle-,
and low-income countries need to come together to develop a common strategy to find
solutions at the levels of policy, health care delivery, health communication, and
education under a platform of global cooperation. In fact, many developing countries
are now caught in a stage of transition in which they face a growing burden of allergic
diseases amongst other non-communicable diseases on top of the ongoing health problems
of communicable diseases.
Efforts targeting allergic diseases are still very fragmented. The WAO White Book
on Allergy not only presents data on the growing epidemic of allergy worldwide, but
also puts forward a set of recommendations the
“Declaration of Recommendations
” targeted towards governments and health care policy makers, 1) need for epidemiological
studies to assess the true burden of allergic diseases globally; 2) need to implement
appropriate environmental control measures to reduce triggers and risk factors like
smoking and outdoor pollutants and develop adequate preventative measures; 3) need
to increase the availability of adequate trained personnel to diagnose and treat allergic
diseases as well as make provisions for better availability and affordability of drugs;
4) need to bridge the knowledge gap in allergic diseases and asthma leading to increased
capacity building; 5) need to increase the clinical expertise in treating allergic
diseases and asthma; 6) need to make efforts to increase public awareness and work
towards developing innovative preventative strategies.
Global partnerships may encourage rapid and cost-effective scientific innovations.
Large multicounty consortia are also needed to provide data from multiethnic populations
for studies of genes and epigenetic phenomena, which could unravel the pathophysiological
mechanisms behind some noncommunicable diseases; such consortia could also help to
develop interventions that promote health globally. While the World Allergy Organization
has been making constructive steps in various ways in the last years towards addressing
this public health issue, a collaborative effort by the American Academy of Allergy
Asthma and Immunology (AAAAI), the European Academy of Allergy and Clinical Immunology
(EAACI), the American College of Allergy Asthma and Immunology (ACAAI) and the World
Allergy Organization (WAO) called International Collaboration in Asthma, Allergy and
Immunology (iCAALL) has been working towards addressing allergic diseases through
dissemination of knowledge and raising awareness at various levels.
Globalization is creating an interdependence that affects both the risks of disease
and their potential solutions. Global connections are much more apparent in the case
of communicable infectious diseases, since viruses and bacteria are more readily perceived
as cross-border threats; consequently, these diseases prompt global cooperation, as
evidenced by the Global Fund to Fight AIDS, Tuberculosis, and Malaria, among other
initiatives. Although we must continue to address these threats, we must also increase
the sense of urgency regarding noncommunicable diseases that are “communicated” by
means of the global promotion of products and lifestyles, lest they insidiously undermine
the health and wealth of nations. We have a great opportunity: global noncommunicable
diseases can unite high-, middle-, and low-income countries in a common purpose, given
their common causation, increasingly similar mortality rates and economic burdens
worldwide, and generalizable preventive and curative solutions. The first challenge,
however, will be to energize policymakers to recognize the need and that opportunity.
Therefore efforts should be targeted towards a common goal of reducing the burden
of allergic diseases, developing cost-effective innovative preventive strategies and
a more integrated, holistic approach to treatment thereby preventing premature and
unwanted deaths and improving the quality of life of patients.