What links dust mites, shellfish, and insect food allergies?

New research from subtropical Spain shows how exposure to common household mites may prime the immune system to react to edible insects, even in people who’ve never tried them.

Study: The Allergy Crossroads of Subtropical Regions: Mites, Crustaceans, and the Rise of Edible Insects. Image Credit: Choksawatdikorn / Shutterstock

In a recent article published in the journal Nutrients, researchers in Santa Cruz de Tenerife, Spain, investigated how 634 people living in a subtropical area with high exposure to storage mites and house dust responded to edible insects (EIs) to understand links between emerging food sensitivities and cross-reactivity. They observed that approximately 22% of participants reacted to at least one EI, and that nearly 96% of reactive individuals also responded to mite allergens, suggesting that EI sensitization may be influenced by environmental factors rather than being incidental.

Background

As EIs gain attention as a sustainable food source, concerns about their potential to cause allergies are increasing. The European Commission recently approved a powder derived from yellow mealworms for consumption, but the European Food Safety Authority has cautioned about allergy risks, particularly for individuals allergic to mollusks, mites, and crustaceans.

Proteins such as arginine kinase and tropomyosin are shared across mites, crustaceans, and insects and are known to cause immune responses due to their cross-reactivity. This has raised concerns about allergic reactions in individuals sensitized to house dust mites (HDMs), even in the absence of direct exposure to EI.

Reports of such cross-reactivity have led to the term ‘mite-EI syndrome.’ Environmental factors, including allergen exposure and climate, could further shape these immune responses. Researchers can now precisely identify patterns in allergen sensitization using advanced molecular diagnostic tools.

About the study

The research team investigated how mite exposure in a subtropical region may contribute to EI sensitization in individuals with no prior EI consumption, providing insights into emerging food allergies. Tenerife, Spain, provided a relevant setting to explore this issue.

They employed a retrospective study design, utilizing data from 634 patients who sought care at an allergy clinic in 2024. Patients with immunoglobulin E (IgE)-mediated allergic reactions and a suggestive clinical history were included in the study. Individuals taking certain supplements or undergoing specific treatments, as well as those who were pregnant or breastfeeding, were excluded.

Sensitization to edible insects such as locusts, house crickets, and mealworms was assessed using specialized allergy tests. Blood samples were collected, stored at –40°C, and analyzed for total IgE (tIgE) and specific IgE (sIgE) against 282 allergens.

The assay measured sIgE levels ≥ 0.3 kUA/L and included a cross-reactive carbohydrate determinant (CCD) inhibitor to minimize false positives. Sensitizations to arginine kinase and tropomyosin were identified using multiple markers. Results were categorized into five reactivity classes.

Seventeen mite-derived allergens were analyzed along with pan-allergens like arginine kinase, tropomyosin, and troponin-C. Statistical tests used included ANOVA, Kruskal–Wallis, Mann–Whitney U, and Chi-square tests, with logistic regression used to adjust for confounders.

The study’s observational design identifies associations but does not establish causality between mite exposure and EI sensitization.

Findings

About 22% of participants (138 people) showed sensitivity to one or more EIs. Most were male (69%), with a median age of 17. Nearly 60% had both respiratory and food allergies; 16% had food allergies alone, and 26% had respiratory issues like rhinitis or asthma.

Half of those with food symptoms also had seafood allergies. High tIgE levels and a strong family history of atopy were common.

Among sensitized individuals, tropomyosin was the most frequent allergen (64%), followed by troponin-C (29%), arginine kinase (27%), and sarcoplasmic calcium-binding protein (9%). About 47% reacted to all three EIs; some reacted to only one.

Interestingly, 23% showed no reactivity to known pan-allergens, and only 3% did not react to any of the molecules in the test, suggesting the presence of unidentified allergens. Patients with respiratory allergies were also sensitized to dust mites, though reactivity to pan-allergens was rare in this group.

Statistically significant correlations were found between EI sensitization and certain mite allergens, especially tropomyosin (e.g., Blo t 10 and Der p 10). The arginine kinase correlation (e.g., Der p 20) was weaker and may be less clinically relevant.

Conclusions

This study highlights significant cross-reactivity between edible insects and allergens, such as those from mites and crustaceans, due to the shared proteins tropomyosin and arginine kinase.

In mite-prevalent areas, exposure may trigger EI sensitization even without direct consumption. However, 23% of participants showed no known pan-allergen reactivity, indicating the potential presence of novel allergens or low-level responses beyond current detection.

Some individuals were sensitized to EIs without reacting to other known allergens, suggesting EIs may act as primary sensitizers in rare cases.

Limitations include the observational design and lack of clinical food challenges, which are necessary to confirm allergic reactions. More research is needed to explore novel allergens and regional patterns of sensitization.

Although the presence of food-specific IgE doesn’t always indicate a clinical allergy, diagnosing EI allergy requires a comprehensive history, laboratory tests, and possibly oral food challenges.

As EIs become more prevalent, they may independently trigger allergies or act through cross-reactivity, making personalized diagnostics increasingly important.