TOPLINE:

Sensitization to an increasing number of cat or dog allergen molecules was associated with a higher prevalence of asthma symptoms upon pet exposure.

METHODOLOGY:

• Researchers analyzed the prevalence of allergen molecules and assessed whether molecular sensitization to cats and dogs is linked to asthma or rhinoconjunctivitis in 595 teenagers from northern Sweden in 2018.
• The allergen molecules analyzed were Fel d 1, 2, and 4 for cat and lipocalin Can f 1, 2, 3, 4, 5, and 6 for dog.
• A participant was considered sensitized to cat and dog if the serum showed specific immunoglobulin (Ig)E antibody levels ≥ 0.10 kU/L; sensitization to allergen molecules was confirmed using a threshold of ≥ 0.30 ISU for allergen-specific IgE.

TAKEAWAY:

• Among dog‑sensitized participants, Can f 5 allergen was most prevalent, detected in 51.6%.
• Fel d 1 dominated cat sensitization, occurring in 91.2% of participants sensitized to cat.
• Among participants exposed to dogs and cats, sensitization to an increasing number of allergen molecules was associated with an increase in prevalence of asthma.
• Among participants exposed to dogs and cats, sensitization to an increasing number of allergen molecules was associated with an increase in prevalence of rhinoconjunctivitis, but the increase leveled off after co‑sensitization to three.

IN PRACTICE:

"Sensitization to an increasing number of pet specific allergen molecules was associated with an increased risk of having asthma or rhinoconjunctivitis upon cat and dog exposure. This was especially true for sensitization to lipocalins,” the authors wrote. 

SOURCE:

Anna Winberg , PhD, with Umeå University, Umeå, Sweden , was the corresponding author of the study, which was published online on January 15, 2026, in International Archives of Allergy and Immunology.

LIMITATIONS:

This study was limited by its reliance on self ‑ reported symptoms and by the small numbers of participants sensitized to some individual allergen molecules, which reduced the power for subgroup analyses.

DISCLOSURES:

This study was financially supported by the Swedish Heart-Lung Foundation, the Swedish Foundation for Health Care Sciences and Allergy Research, the Swedish Asthma and Allergy Foundation, a regional agreement between Umeå University and Västerbotten County Council, the VISARE NORR fund: Northern County Councils Regional Federation, and Norrbotten County Council. The authors reported having no conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.