(Vienna, 25-09-2026) Children and adults with respiratory allergies react to different allergens: children were found to be significantly more frequently sensitised to house dust mites, whilst adults were more frequently sensitised to outdoor pollen allergens. This pattern was observed in two independent cohorts in Algeria and Turkey. At the same time, asthma was more common among the children studied than among the adults. These are the findings of an international study coordinated by the Medical University of Vienna, which was published in the Lancet journal eBioMedicine.
In allergic sensitisation, the immune system produces specific immunoglobulin E (IgE) antibodies against an allergen. Molecular allergy diagnostics can determine very precisely which individual allergen molecules are recognised in this process. For the current study, the researchers examined IgE reactions to 105 different allergen molecules. Initially, 539 children and adults with allergies from the Algiers region were analysed. The research team then verified the results in a further 272 patients from Istanbul and Samsun in Turkey.
Clear difference between indoor and outdoor allergens
A similar pattern emerged in both populations studied: children with respiratory allergies were more frequently sensitised to major house dust mite allergens. Adults, by contrast, were more likely to react to typical pollen allergens from their respective regions. In Algeria, these included olive and grass pollens; in Turkey, olive and ragweed pollens.
“It is particularly interesting that we were able to observe this pattern in two independent populations on different continents. Children and adults clearly differ significantly in terms of which allergens their immune systems are sensitised to,” says study author Rudolf Valenta from the Center for Pathophysiology, Infectiology and Immunology at MedUni Vienna.
The study does not provide a direct explanation as to why sensitisation patterns differ between age groups. The authors discuss, amongst other things, changes in lifestyle, spending more time indoors, and changes in climate, vegetation and air pollution as possible influencing factors. However, these explanations must be tested in further studies.
Possible implications for asthma and allergy treatment
In both study populations, asthma was more common in children with respiratory allergies than in adults. At the same time, children were more frequently sensitised to key house dust mite allergens. However, a causal link between mite sensitisation and asthma cannot be inferred from the cross-sectional study. Further, long-term studies are required for this.
“The results also show why it is important to have as accurate a knowledge as possible of the relevant allergens. Molecular analyses can help to tailor allergy diagnostics, allergen-specific therapy and, in future, preventive measures more precisely to different population groups,” said Valenta.
Publication: eBioMedicine
Age-related molecular IgE sensitisation to indoor and outdoor respiratory allergens: a two-step cross-sectional study in Algeria and Türkiye
Lydia Lamara Mahammed et al.
eBioMedicine (2026)
DOI: 10.1016/j.ebiom.2026.106484