Climate change and allergies

Patients with chronic respiratory allergic diseases such as asthma and allergic rhinoconjunctivitis are at particular risk due to increased exposure to pollen, as well as the increased concentration and distribution of air pollutants. In fact, CC has both increased the intensity of the pollen season as well as prolonged its duration. Changes in pollen led to increased respiratory allergic disease, evident from correlations between pollen and respiratory disease exacerbations. 

 

We know that climate change has worsened allergies in those with established respiratory allergic disease, but the authors of this review hypothesize that the relationship between climate change and immunologic diseases such as allergies may be more extensive.

 

CC and global warming may result in an erratic immune system and consequently, the emergence of allergic and autoimmune disease in disease-naïve populations.

 

Climate change has dramatically altered the profile of antigens our bodies are exposed to. While many of these

 

antigens are benign, it is possible that the extent of this change has overwhelmed the immune system’s long-standing ability for antigen-specific tolerance, and the increasing molecular mimicry due in part to increasing exposure to allergens, is leading to a rise in immunologic disease.

 

CC can also alter the microbiota composition.

 

The microbiota plays an important role in the maturation of the immune system, in T-cell differentiation and in the tolerance development.

 

Disruption of the microbiome, known as dysbiosis, can lead to a variety of secondary effects within the body.

 

Loss of biodiveristy induced by CC can affect microbiota.

 

A 2019 global report released by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) announced that biodiversity “is declining faster than at any time in human history”. Climate change was cited as a leading factor for this decline.

 

A reduced contact between people and a biologically diverse natural environment may adversely affect the microbiota and its immunomodulatory capacity.

 

The World Allergy Organization (WAO) declared that “biodiversity loss leads to reduced interaction between environmental and human microbiotas, which in turn may lead to immune dysfunction and impaired tolerance mechanisms.

 

The WAO suggested that these changes may account in part for the increase in the prevalence of asthma, allergy and inflammatory disease.

 

The impact of CC and global warming on health and in particular on allergic respiratory diseases appear more and more relevant. CC is no longer an issue for future generations. It is affecting every one of us, now.

 

 

 

Carly Ray and Xue Ming. Climate Change and Human Health: A Review of Allergies, Autoimmunity and the Microbiome. Int. J. Environ. Res. Public Health 2020, 17, 4814; doi:10.3390/ijerph17134814

Article by Marcella Lauletta