[The impact of heat waves in allergic diseases: Group Report of the Environmental Committee of the Mexican College of Clinical Immunology and Allergy (CMICA)].

BACKGROUND

The increasing frequency and intensity of heat waves, as a consequence of climate change, represents a growing risk to public health, particularly in populations with allergic and respiratory diseases.

OBJECTIVE

A review to describe the available evidence on the relationship between heat waves and the exacerbation of allergic diseases, with emphasis on the environmental and pathophysiological mechanisms involved.

METHODS

A structured search was conducted in Scopus and Web of Science (2015-2025), complemented with regional literature, identifying 304 references. After applying inclusion and exclusion criteria, 120 full-text articles were assessed, and 79 were included in the qualitative synthesis.

RESULTS

Evidence confirms that heat waves are associated with an increase in hospital admissions for asthma and with more frequent consultations for atopic dermatitis in pediatric patients. The mechanisms identified include intensified pollen production and dispersal, synergy with air pollutants, disruption of the epithelial barrier, and activation of transient receptor potential (TRP) channels.

CONCLUSIONS

The lack of well-defined study protocols for managing allergic patients during heat waves represents a gap not only in Mexico and Latin America but also worldwide. Key limitations include the absence of standardized definitions, the scarcity of multi-exposure analysis models, and the lack of comprehensive strategies for urban mitigation and clinical adaptation to protect the most vulnerable groups. In the case of allergic rhinitis, the available data remain inconclusive regarding exacerbations associated with heat waves.