Submitted:
03 April 2026
Posted:
07 April 2026
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Abstract
Background & Aims: Allergic diseases affect 40% of the world's population, a proportion that is increasing due to various factors associated with environmental and meteorological changes related to global warming. However, little has been written about which specific allergens are causing this increase in allergic disease. Changes in lifestyle and food consumption patterns in the population may also be influencing this increase. Methods: We present a longitudinal, real-life observational study conducted over the last five years in our allergic population treated at the Allergy Department of the Rio Hortega University Hospital (HURH), (21,564 sensitized patients, aged between 0 and 99 years) and the student of 5th Medicine course of our University (22-23 years old), (diagnosed by prick test, specific immunoglobulin E positivity, and provocation if necessary) from 2021 to 2025. We aim to find out which allergens are increasing or decreasing, and compare them with the trends in positivity obtained in a group of 683 medical students who underwent the same tests in the practical class included in the teaching report for the Immunopathology and Allergy course. Results: In 2021, after the lockdown due to the pandemic, only 6 allergens were more detected significantly as more risk to sensitize the student group respect to general patients attended in surgery (grasses, olive, cupressus and plane tree pollen and profiline). Food sensitization was not detected. In 2022, nine more relevant allergens were more detected in students than in the general population. Dog and cat appear as important allergens, and 5 food plant allergens were included. These foods are also detected in subsequent years. Anisakis remain highly significant allergen in this young people, despite all students being aware of the freezing measures. Conclusions: There appears to be a clear relationship between climate, lifestyle, economy, and consumption and allergic conditions, which may be based on a possible shift away from the Mediterranean diet due to an increase in pathologies associated with plant panallergens (LTPS and profilins) related to pollen.
Keywords:
allergens
; food allergy
; trends
; climate change
; lifestyle
; economy
; mediterranean diet
Introduction
Allergic diseases affect up to 40% of the world's population, a proportion that is increasing with environmental changes related to global warming [1,2,3].
We often wonder whether this increase in allergies is due to better diagnosis, climate change, pollution, changes in diet, or lifestyle. And if the combination of all these reasons could be the cause.
Recent studies [1] confirm that environmental pollution has increased the incidence of allergic diseases in terms of epidemiology and healthcare burden. The effect of environmental pollution is predominantly caused by pollutants: (NO2) and particles <2.5 µm and respiratory allergic diseases (asthma and rhinitis) and dermatological diseases: atopic dermatitis.
As for food allergies, the annual reports produced by AECOSAN (Spanish Agency for Consumer Affairs, Food Safety, and Nutrition) and the Spanish Ministry of Agriculture, Fisheries, and Food provide comprehensive information on the consumption of food and beverages by residents in Spain since 2021 [4], and even among university students [5].
An analysis of population trends, tourism, and the number of households shows that over the last five years, Spain's population has remained stable compared to the previous year, with a slight increase of 0.2%, bringing Spain's population to 49.15 million in May 2025, compared to 47.326.687 in 2021 (data from the National Institute of Statistics) [6].
This growth is driven by an increase in households made up of young people and independent adults, single-parent households, adult couples without children, and retirees. However, there has been a decrease in the number of households with children, regardless of age, as well as households made up of young couples without children.
The current situation is marked by recovery from the global health crisis caused by COVID-19, the conflict between Ukraine and Russia, Gaza and Middle Eastern wars, economic changes promoted by the US presidency, and rising inflation in general. The gradual return to normality after the pandemic, which led to a reduction in consumption within the home and an increase in consumption outside the home, travel, and leisure, means that, if we add consumption inside and outside the home, a total of 30,946.87 million kilos or liters of food and beverages were purchased in 2022. This is 7.1% less than the amount consumed during the previous year (2021), and this decline is continuing, especially in more expensive foods such as fish, meat, and olive oil. In 2024, a total of 30,668 million kilos or liters of food and beverages were consumed. This represents a slight decrease of 0.2% compared to the previous year, although total spending increased by 2.4%, reaching 119.667 billion euros. In 2025, each Spaniard consumes 680 kg of food, but its composition has undergone changes.
With all this data and that obtained from daily consultations with our patients in our Allergy Department and tests carried out on a homogeneous sample of young 5th-year medical students, we aim to study which allergens are most sensitizing, whether there is any trend in the increase or decrease in sensitivity to certain allergens, and whether there are any differences between groups associated with age, type of diet, or lifestyle.
Methods
We present a longitudinal, real-life observational study conducted over the last five years in our allergic population treated at the Allergy Department of the Rio Hortega University Hospital (HURH), (approximately 9,000 patients annually) and the student of 5th Medicine course of our University (22-23 years old).
We selected patients aged between 0 and 99 years with allergic symptoms and positivity to an allergen. Allergic symptoms were defined by positive prick and specific immunoglobulin E tests for an allergen and provocation if necessary. We excluded the patients of the same age of our Medicine students.
For the prick test, we used diagnostic allergens from ALK Abelló Madrid, with a battery of 42 aeroallergens and major foods, to which complementary batteries were added depending on the patient's clinical presentation. IgE was measured by InmunoCAP Thermofisher Diagnostics, Uppsala, Sweden.
Our objective was to identify the 25 most relevant allergens in our population (environmental and food) that have caused the most allergic symptoms from 2021 to 2025. Finally, 21,564 sensitized patients were detected, ranging in age from 0 to 99 years. The average age was 46±4.2 years.
We aim to identify which allergens are increasing or decreasing, and compare them with the trends in positive results obtained in a group of 683 fifth-year medical students, aged between 21 and 23, who underwent the same prick tests as our patients in the same years, during the practical class included in the teaching report for the Immunopathology and Allergy course. These tests have been approved from an ethical standpoint by the University of Valladolid, teaching reports, and research reports from the Faculty of Medicine. A total of 683 students were studied. They were given informed consent.
The work has been carried out in accordance with the Code of Ethics of the World Medical Associations.
Table 1.
shows the number of patients from the general population and students who consented to the study.
Table 1.
shows the number of patients from the general population and students who consented to the study.
| Year | Patients HURH | Estudents |
|---|---|---|
| 2021 | 3200 | 135 |
| 2022 | 3920 | 139 |
| 2023 | 4813 | 140 |
| 2024 | 4801 | 130 |
| 2025 | 2801 | 139 |
A nutritional survey adapted to the guide “General principles for the collection of national food consumption data in view of a Pan-European dietary survey,” published by the European Food Safety Authority (EFSA) in 2009, is added to this group of students. [7]
Statistical Analysis
The t-test was used to compare means and the Chi-square test for tests of independence. The odds ratio of the risk to be a student in sensitization to different allergens was calculated. The odds ratio expressed in the results was calculated as the ratio between the odds of achieving sensitization to different allergens in general population attended in our hospital compared with sensitization in students.
Results
Descriptive Analysis
The following tables show the 25 most relevant allergens in our population (environmental and food) that have caused the most allergic symptoms (diagnosed by prick test, specific immunoglobulin E, and provocation test if necessary) from 2021 to 2025.
Allergens that have increased are shown in bold, and those that have decreased are shown in italics.
In Table 2, which details the 25 most detected allergens during 2021, we can see a parallelism of greater response to the same allergens between the general population and the student population, but the highest percentages are for sensitization to grass and tree pollen (cypress and plane tree), domestic animal allergens, and Alternaria spores, which are common in our largely cereal-growing region during the summer [8].
Sensitivity to pollen was lower in 2021 than in subsequent years, possibly due to the effects of lockdown. Among students, progressive sensitivity to grass pollen was detected in around 40% of them, although 28% had not experienced any allergic symptoms.
In terms of food allergens, sensitivity to peach lipid transfer protein (LTP) stands out, which has been extensively studied in relation to pollen sensitivity or pollen-fruit syndrome [9], as well as sensitivity to anisakis, nuts, and profilin, with lower sensitivity to milk and wheat.
In the following tables, the percentage of positive responses in our students was around 40%. However, allergic pathology was only observed in 33% of sensitized students.
In 2022, there will be an increase in the general population of cat, grass, dog, ovomucoid, egg yolk, soy, and profilin. There will be a decrease in raygrass, pteronyssinus, anisakis, LTP peach, hazelnut, peanut, walnut, egg, and milk. Of particular note is the decrease in wheat and milk and the increase in soy. Among students, there is an increase in ryegrass pollen, cat, dog, plane tree pollen, alternaria, anisakis, LTP, soy, and profilin. There is a decrease in milk, egg, and, significantly, wheat. Table 3.
In 2023, the predominant allergens continue to be pollens, with a notable increase in sensitivity to Bermuda grass (Cynodon dactylon) and pets (dogs and cats). In terms of food, there is a notable increase in sensitivity to anisakis, soy, LTP, and profilin among the student population (Table 4)
In 2024 (Table 5), an increase in sensitivity to dogs, mites, plane tree pollen, wheat, soy, and profilin was observed in the general population. The allergens that have caused the most allergic symptoms continue to be grass pollen, followed by plane tree pollen, which has increased, probably due to the significant peak in pollination recorded in April. Next in frequency is sensitization to cats, followed by dogs, which has also increased compared to the previous year. Sensitivity to mites has increased, possibly associated with publicity, with the predominant species being Dermatophagoides pteronyssinus and the storage mite Lepidoglyphus destructor (found in stored grain and feed). Among students, there has been a very significant increase in sensitization to grass pollen, especially grass, and also to plane tree pollen.
As for food allergies, they have affected 1,269 patients (47% of allergy sufferers). The most important allergen continues to be anisakis, with increased sensitivity to peanuts and walnuts and decreased sensitivity to eggs and milk, as well as to LTPs and profilins. Sensitivity to profilin and nuts has decreased. Wheat and milk remain very low.
In 2025, the trend remains similar, with an increase in sensitivity to grass pollen in both groups, but in the student group, there is an increase in sensitivity to pet epithelia and an increase in sensitivity to LTP in students. Table 6.
Analytical Study
Table 7 identify which allergens are increasing significantly in the group of 683 students during the last five years, comparing with the general allergy people, including p values and Odds ratio.
In 2021, after the lockdown due to the pandemic, only 6 allergens were more detected significantly as more risk to sensitize the student group respect to general patients attended in surgery (grasses, olive, cupressus and plane tree pollenand profiline). Food sensitization was not detected.
In 2022, nine more relevant allergens were more detected in students than in the general population. Dog and cat appear as important allergens (pets that were widely purchased starting that year, (IPMARK inform https://ipmark.com/informes/mascotas-2025/), and 5 foods are now included. These foods are also detected in subsequent years, although peanuts become more prominent among nuts. Anisakis simplex remain highly significant allergen in this young people, despite all students being aware of the freezing measures.
Discussion
There is sufficient data to show an increase in allergic diseases and in food allergies [1,2,3]. Subclinical sensitization has also been demonstrated in the form of positive tests for allergens that have not yet triggered symptoms or have been tolerated by the immune system [9]. This is more common in young people, as we have seen in our students.
Pollen appears to be the most sensitizing allergen source in our country [10]
It is true that the concentration of atmospheric pollen has not changed significantly in recent decades, but the period during which pollen remains in the air we breathe has changed due to global warming, which causes species to pollinate earlier and for longer [11]. As a result, pollen has gone from being a seasonal allergen to a perennial cause of allergic diseases.
Pollen has undergone alterations in its metabolic processes, increasing stress proteins, which are proteins with high allergenic potential. There is a reduction in photosynthesis rates, total protein synthesis, and growth rates [1,2,3].
Attempts have been made to link the increase in pollen aggressiveness to the decrease in rainfall, but although we associate drought with weather conditions and lack of rain, most of our river basins have not seen such a significant decrease. Studies over the years have warned of an increase in evaporation due to an increase in forest area. Invasive and unproductive species have also caused an increase in pollen [1].
Another factor that may influence this is ethnicity and genetics [12]. However, studies have been conducted that confirm that across a country (for example, the United States), the proportion of people with allergies is the same. Only the substance that each person rejects varies. It is known that there is great genetic diversity in the US. Immigration from all over the world, but this seems to have no influence in the allergy rate [1,11,12].
This data supports the idea that our exposome, everything that surrounds us, the air we breathe, and what we eat may be the source [13]. Allergies seem to be linked to a state of well-being, to a developed and resource-consuming economy, as was seen, for example, when the two Germanys were unified.
Climate change, which increases the drying power of the atmosphere, has undoubtedly had an influence [1,2,3], but even more so has rural abandonment and difficulties in livestock farming, which has led to an increase in the spread of weeds, which in turn become fuel for fires. Global warming has increased the time of exposure to pollen. As a result, the number of people allergic to the most allergenic pollens has doubled in the last 10 years. [1].
We are particularly surprised by the rise in food allergies, which is leading us to adopt increasingly restrictive diets. If humans have been eating milk, eggs, and fruit for millennia, why have we suddenly stopped tolerating them? The reason is perhaps that these aren´t the same milk, eggs or fruits that our grandparents or mothers ate, and they passed on their tolerance to us. According to our results, fruit allergies have increased by 34% in the last 10 years, and the Rosaceae family, specifically peaches, are responsible for 25.7% of food allergies in Spain [10]. The natural progression of food allergies in children is toward tolerance. Although childhood food allergies tend to disappear with age, this does not happen un the same way or at the same rate with all foods, although currently there is no data available to predict individual prognoses. The longer a reaction continues, or the older the child is when a food challenge confirms a hypersensitivity, the less likely the reaction is to disappear. It will also depend on the type of food involved. Children with hypersensitivity to peanuts or fish are unlikely to experience a resolution of their reactions, especially if the problems persist for several years. In the case of milk allergy, persistence increase if the parents are smokers, if the child is male, if the mother is not Caucasian, and if there is sensitization to casein. Early milk sensitization increases the likelihood of sensitization to other allergens (80% probability of rhinitis/asthma by puberty). Egg sensitization normally achieves tolerance by age 3, but a positive egg response at 12 months is a highly predictive marker (PPV 78%) of sensitization to aeroallergens by age 3. If peanut hypersensitivity persists into adolescence, tolerance testing is not recommended. There is limited data on persistence with wheat, despite it being a food introduced early in infant diets, 92% of adults with food allergy have sensitization to at least one aeroallergen and 70% of adults with food allergy have a history of pollen allergy.
Sensitivity to certain foods is related to the response to pollen that is most prevalent in the geographical areas where the affected population lives [13]. Our patients live in an area where wild and cultivated grasses are predominant, causing the sensitivities that we have been able to detect. We highlight cross-sensitivity with fruits, which has been investigated in many studies on the antigenic relationship between pollen and fruits and vegetables [13].
In terms of changes in our diet, the COVID lockdown period led to an adaptation to non-perishable foods and a decrease in the daily purchase of bread, vegetables, and fruit. In 2022, there are no major differences in the composition of the household shopping basket, as it continues to consist of the same main categories as in 2021: a prevalence of fruit, fresh vegetables, milk, and dairy products, which account for 42.4% of the volume of food consumed in 2022. However, per capita consumption has fallen compared to 2021 in almost all categories, but especially in fresh foods such as fruit, vegetables, and legumes, as well as meat and fish. There has also been a reduction above the food average in the consumption of various dry food products such as sugar and flour, as well as oil and wine in the case of beverages [6]. This trend has become more pronounced in subsequent years, especially after the tariffs imposed by the US in 2025, compounded by a 2.4% increase in food spending due to rising prices. Some foods, such as fruit, have seen an 18% increase in price over the last year. In line with these data, our younger patients seem to be adapting to a different diet from older people, also depending on whether they live independently or with their families because they are unable to become independent due to financial problems, a growing trend at present.
A nutritional survey of our students shows a gradual shift away from the Mediterranean diet, with a decrease in the consumption of fruit, milk, and dairy products (although these are being replaced by soy milk and other products) and a decline in bread consumption, although the consumption of industrial baked goods persists. Fish and meat are hardly consumed, although the consumption of seafood and raw or lightly cooked fish is increasing due to a preference for Asian cuisine, which is more economical. The consumption of inexpensive vegetables is increasing among the vegan and vegetarian population, and grocery spending is increasing among celiac patients and patients with non-celiac wheat intolerance [14].
In our study, we observed a progressive decrease in wheat consumption, similar to other areas [15,16], especially among students, who rarely buy bread from bakeries, with flour consumption coming mainly from other packaged baked goods.
Per capita consumption of cereals at the end of 2022 stands at 1.58 kilograms per person per study period, equivalent to a contraction of 4.3%, which means consuming 0.07 kilograms less per person. The highest proportion of per capita consumption is in packaged cereals, with an intake of 1.58 kilograms per year, while on average each individual consumes 0.51 kilograms of fiber-rich cereals [6,7].
Total wheat consumption in 2024 was 30.668 million kilograms/liters, a slight decrease of 0.2% compared to 2023. Average consumption per person was 680 kg/l, representing a decrease of 1.5% [17].
Currently, thanks to the development of necessary biotechnology, crops have been enhanced with pathogen-resistant proteins to increase their yield, so that they can be stored in chambers, treating the seeds so that they can germinate without being damaged by fungi or insects in the soil. Unfortunately, these defense proteins have behaved like the most aggressive allergens. For many years, we have been working with researchers from the School of Agricultural Engineering to study the allergenic power of foods, especially cereals, other seeds, and fruits [15]. The general population believes that vegetables are the most natural foods, and there are more and more vegans and vegetarians, yet vegetables are the sources of the most aggressive allergens. That is why vegetable allergies are very common in these patients.
According to current figures, fruit allergies have increased by 34% over the last 10 years, with the Rosaceae family, and peaches in particular, accounting for 25.7% of food allergies in Spain [10]. Of the severe reactions caused by food in Spain, 44.7% are caused by fruits and seeds, and of these, 60% are caused by sensitization to LTPs [10].
In Spain, food prices have risen significantly in recent years. In 2023, the average increase was 11.8%, exceeding overall inflation. Although there has been a slowdown in recent months, with a 4.2% increase in June, this remains a concern for consumers. Factors such as rising energy costs and extreme weather events have contributed to this situation, which in 2025 is exacerbated by an increase in the price of foods such as fruit, which has risen by 18% compared to the previous year, making these foods less accessible to low-income populations, including young people.
There has also been an increase in awareness among young people of Anisakis, a parasite that is not controlled despite the widespread use of freezing [18]. Anisakis remain highly significant allergen in this young people, despite all students being aware of the freezing measures, demonstrating that perhaps this measure is only partially effective, due that anisakis have heat stable allergens.
It is worth noting that young people have a taste for foods that include raw fish. Consumption of cow's milk has also declined among this population, being replaced by dairy products from different sources [19].
Conclusion
There appears to be a clear relationship between climate [11], lifestyle, economy, and consumption and allergic conditions, which may be based on a possible shift away from the Mediterranean diet due to an increase in pathologies associated with plant panallergens (LTPS and profilins, 20,21) related to pollen. The analysis of these data may warrant further study with a view to the prevention and treatment of allergic diseases.
Acknowledgments
We would like to thank Professor Raúl Izquierdo, from the Investigation Unit. Hospital Universitario Río Hortega. Valladolid. Spain, for the technical assistance needed to conduct this study. We also thank sources from the Ministry of Agricultura, Pesca y Alimentación who provided us with data on food consumtion in our nation.
Declaration of interests
All authors declare no potential conflicts of interest.
Funding statements
This research did not receive any specific grant from funding agencies in te public, commercial or not for profit sectors.
Author Contributions
the authors: Alicia Armentia, Sara Fernández and Sara Martín have participated in the conception, design of the study, analysis and interpretation of the data. Luis Cuellar and Sara Martin-Armentia carried out the nutritional study of adults and children patients. Alicia Armentia, Blanca Martín and Ignacio González-Rodríguez carried out all laboratory analyses. Delia Fernandez and Aurora Sacristan, have contributed to in the generation, analysis and interpretation of epidemiological and pollen data results with the rest of the authors. All authors have participated in the preparation and critical revision of the paper and all authors have seen and approved the final version of the manuscript. No authors have any conflict of interest in connection with this paper. The authors also follow all recommendations of the ICMJE. No one eligible for authorship has been excluded from the list of authors. Data sharing statement October 16, 2025.
Ethical approval
These tests have been approved from an ethical standpoint by the University of Valladolid, Spain, teaching reports, and research reports from the Faculty of Medicine (NRP: 1236011668 A0500). We obtain form Valladolid University and SACYL all permission to data base use.
Declaration of Generative AI and AI-assisted technologies in the writing process
AI has not been used in this work.
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Table 2.
YEAR 2021.
| ALERGEN | Nº POSITIVES GENERAL POPULATION | % TOTAL 3200 POSITIVES | Nº POSITIVES 135 STUDENTS |
% TOTAL 135 STUDENTS |
|---|---|---|---|---|
| Ryegrass | 280 | 8.75 | 19 | 14 |
| Cat | 99 | 3 | 4 | 2.9 |
| Bermuda grass | 150 | 4.7 | 12 | 8.5 |
| Dog | 122 | 3.8 | 6 | 4.4 |
| Olive pollen | 152 | 4.7 | 12 | 8,5 |
| Alternaria | 128 | 4 | 9 | 2 |
| Cuppressus pollen | 99 | 3 | 9 | 2 |
| D. pteronyssinus | 98 | 3.1 | 8 | 5.9 |
| Plane tree pollen | 100 | 3.1 | 13 | 9.6 |
| Anisakis | 120 | 3.8 | 6 | 4.4 |
| LTP* | 160 | 6.9 | 6 | 4.4 |
| Hazelnut | 92 | 2.8 | 7 | 5.2 |
| Peanut | 88 | 2.7 | 6 | 4.4 |
| Wallnut | 83 | 2.5 | 7 | 5.2 |
| Almod | 79 | 1,4 | 4 | 2.9 |
| Ovomucoide | 70 | 2.2 | 2 | 1.5 |
| Egg White | 62 | 1,9 | 2 | 1.5 |
| Milk | 62 | 1,9 | 2 | 1.5 |
| Caseine | 61 | 1,9 | 2 | 1.5 |
| Chenopodium pollen | 58 | 1,8 | 4 | 2.9 |
| Egg yolk | 50 | 1,5 | 2 | 1.5 |
| Wheat | 69 | 2,1 | 2 | 1.5 |
| Soy | 51 | 1,6 | 1 | 0.7 |
| Ovoalbumin | 62 | 1,9 | 2 | 1.5 |
| Profiline | 58 | 1,8 | 12 | 8.5 |
*LTP: lipid transporter protein.
Table 3.
YEAR 2022.
| ALERGEN | Nº POSITIVES GENERAL POPULATION |
% TOTAL 3920 POSITIVES | Nº POSITIVES 139 STUDENTS |
% TOTAL 139 STUDENTS |
|---|---|---|---|---|
| Ryegrass | 311 | 7.9 | 59 | 42.4 |
| Cat | 169 | 4.3 | 14 | 10 |
| Bermuda grass | 230 | 5.8 | 20 | 14.3 |
| Dog | 160 | 4 | 16 | 11,4 |
| Olive pollen | 150 | 3.8 | 12 | 8,5 |
| Alternaria | 142 | 3.6 | 10 | 7.2 |
| Cupressus pollen | 115 | 2.9 | 9 | 6.4 |
| D. pteronyssinus | 80 | 2 | 8 | 5.7 |
| Plane tree | 120 | 3 | 15 | 10.7 |
| Anisakis | 99 | 2.5 | 26 | 18.7 |
| LTP | 120 | 3 | 20 | 14.4 |
| Hazelnut | 90 | 2.3 | 7 | 5 |
| Peanut | 80 | 2 | 6 | 4.3 |
| Wlanut | 80 | 2 | 7 | 5 |
| Almond | 82 | 2.1 | 4 | 2.8 |
| Ovomucoide | 70 | 1.7 | 2 | 1.4 |
| Egg White | 59 | 1.6 | 2 | 1.4 |
| Milk | 58 | 1.4 | 2 | 1.4 |
| Caseine | 58 | 1.4 | 2 | 1.4 |
| Chenopodium | 61 | 1.5 | 4 | 2.8 |
| Egg yolk | 59 | 1.6 | 2 | 1.4 |
| Wgeat | 32 | 0.8 | 1 | 0.7 |
| Soy | 70 | 1.7 | 7 | 5 |
| Ovoalbumin | 57 | 1.4 | 2 | 1.4 |
| Profilin | 99 | 2.5 | 12 | 8.6 |
Table 4.
YEAR 2023.
| ALERGEN | Nº POSITIVES GENERAL POPULATION |
% TOTAL 4813 POSITIVES | Nº POSITIVES 140 ESTUDENTS |
% TOTAL 140 STUDENTS |
|---|---|---|---|---|
| Ryegrass | 392 | 8,1 | 60 | 42.8 |
| Cat | 223 | 4.6 | 18 | 12.8 |
| Bermuda grass | 264 | 5.4 | 30 | 21.4 |
| Dog | 201 | 4.2 | 20 | 14.3 |
| Olive pollen | 153 | 3,1 | 12 | 8.5 |
| Alternaria | 190 | 3.9 | 12 | 8,5 |
| Cupressu pollen | 114 | 2,3 | 9 | 6,4 |
| D. preronyssinus | 114 | 2,3 | 7 | 5 |
| Planetree | 107 | 2,2 | 18 | 12.8 |
| Anisakis | 98 | 2,03 | 29 | 20.7 |
| LTP | 95 | 1,9 | 21 | 15 |
| Hazelnut | 93 | 1,9 | 6 | 4.2 |
| Peanut | 90 | 1,8 | 6 | 4.2 |
| Walnut | 86 | 1,7 | 7 | 5 |
| Almond | 84 | 1,6 | 4 | 2.8 |
| Ovomucoide | 77 | 1,5 | 2 | 1.4 |
| Egg White | 68 | 1,4 | 2 | 1.4 |
| Milk | 62 | 1,2 | 2 | 1.4 |
| Caseine | 61 | 1,2 | 2 | 1.4 |
| Chenopodium | 61 | 1,2 | 4 | 2.8 |
| Egg yolk | 59 | 1,2 | 2 | 1.4 |
| Wheat | 25 | 0.5 | 2 | 1.4 |
| Soy | 68 | 1,4 | 6 | 4.2 |
| Ovoalbumin | 57 | 1,1 | 2 | 1.4 |
| Profilin | 77 | 1,5 | 18 | 12.8 |
Table 5.
YEAR 2024.
| ALERGEN | Nº POSITIVES GENERAL POPULATION 2024 |
% TOTAL 4801 POSITIVES 2024 | Nº POSITIVES 130 STUDENTS |
% TOTAL 130 STUDENTS |
|---|---|---|---|---|
| Ryegrass | 199 | 6.4 | 61 | 46.9 |
| Cat | 132 | 3.5 | 20 | 15.3 |
| Bermuda grass | 265 | 5.5 | 32 | 24.6 |
| Dog | 99 | 3,2 | 22 | 16.9 |
| Olive pollen | 99 | 3,1 | 11 | 8.4 |
| Alternaria | 78 | 2,7 | 12 | 9.2 |
| Cupressus pollen | 20 | 2.3 | 6 | 4.6 |
| D. pteronyssinus | 74 | 2,3 | 6 | 4.6 |
| Planetree | 109 | 2.3 | 19 | 14.6 |
| Anisakis | 72 | 2 | 23 | 17.6 |
| LTP | 12 | 0.2 | 21 | 16.1 |
| Hazelnut | 62 | 1.3 | 5 | 3.8 |
| Peanut | 63 | 1.8 | 5 | 3.8 |
| Wallnut | 62 | 1.7 | 4 | 3 |
| Almonds | 46 | 1,6 | 2 | 1.5 |
| Ovomucoide | 31 | 1,5 | 2 | 1.5 |
| Egg White | 29 | 1.4 | 2 | 1.5 |
| Milk | 33 | 1,2 | 2 | 1.5 |
| Caseine | 33 | 1,2 | 2 | 1.5 |
| Chenopodium | 37 | 1,2 | 2 | 1.5 |
| Egg yolk | 26 | 0.7 | 2 | 1.5 |
| Wheat | 34 | 0.7 | 1 | 0.7 |
| Soy | 77 | 2.7 | 5 | 3.8 |
| Ovoalbumin | 22 | 1.1 | 1 | 0.7 |
| Profilin | 25 | 1.1 | 12 | 9.2 |
Table 6.
YEAR 2025.
| ALERGENO | Nº POSITIVES GENERAL POPULATION 2025 |
% TOTAL 2001 POSITIVES 2025 | Nº POSITIVES 130 ESTUDENTS |
% TOTAL 138 ESTUDENTS |
|---|---|---|---|---|
| Ryegrass | 89 | 4.5 | 61 | 46.9 |
| Cat | 78 | 3,8 | 20 | 15.3 |
| Bermuda grass | 65 | 5,5 | 32 | 24.6 |
| Dog | 45 | 3,2 | 22 | 16.9 |
| Olive pollen | 32 | 1.5 | 11 | 8.4 |
| Alternaria | 28 | 1.4 | 12 | 9.2 |
| Cupressus pollen | 10 | 0.4 | 6 | 4.6 |
| D. pteronyssinus | 32 | 2,3 | 6 | 4.6 |
| Planetree | 45 | 1.6 | 19 | 14.6 |
| Anisakis | 30 | 1.5 | 23 | 17.6 |
| LTP | 9 | 1,9 | 21 | 16.1 |
| Hazelnut | 31 | 0.4 | 5 | 3.8 |
| Peanut | 29 | 1.4 | 5 | 3.8 |
| Wlanut | 28 | 1,4 | 4 | 3 |
| Almond | 22 | 1,1 | 2 | 1.5 |
| Ovomucoide | 10 | 0.4 | 2 | 1.5 |
| Egg White | 8 | 0.3 | 2 | 1.5 |
| Milk | 12 | 0.5 | 2 | 1.5 |
| Caseine | 12 | 0.5 | 2 | 1.5 |
| Chenopodium | 14 | 0.7 | 2 | 1.5 |
| Egg yolk | 13 | 0.6 | 2 | 1.5 |
| Wheat | 6 | 0.3 | 1 | 0.7 |
| Soy | 13 | 0.6 | 5 | 3.8 |
| Ovoalbumin | 6 | 0.3 | 1 | 0.7 |
| Profilin | 15 | 0.7 | 12 | 9.2 |
Table 7.
Increase of hypersensitivity to allergens in students during the last 5 years.
| Year | Alergen | p-value | Odds Ratio | IC 95% Inferior | IC 95% Superior |
|---|---|---|---|---|---|
| 2021 | Rye grass | 0,033919034 | 1,708128079 | 1,035687088 | 2,817165114 |
| 2021 | Bermuda grass | 0,026129379 | 1,983739837 | 1,072493357 | 3,669229013 |
| 2021 | Olive pollen | 0,029370343 | 1,9563543 | 1,057976739 | 3,617586291 |
| 2021 | Cupressus pollen | 0,021606606 | 2,237373737 | 1,105244596 | 4,529170518 |
| 2021 | Plane tree | <0,0001 | 3,303278689 | 1,802922833 | 6,052200292 |
| 2021 | Profiline | <0,0001 | 5,285113541 | 2,766936189 | 10,09507384 |
| 2022 | Rye grass | <0,0001 | 8,558319936 | 5,99648558 | 12,21462791 |
| 2022 | Cat | 0,001296454 | 2,485869822 | 1,400942627 | 4,410993466 |
| 2022 | Bermuda grass | <0,0001 | 2,696382901 | 1,648519352 | 4,410309616 |
| 2022 | Dog | <0,0001 | 3,056910569 | 1,773617678 | 5,268724112 |
| 2022 | Olive pollen | 0,004442091 | 2,37480315 | 1,285198212 | 4,388186932 |
| 2022 | Alternaria | 0,029277348 | 2,062452233 | 1,060848881 | 4,009722109 |
| 2022 | Cupressus pollen | 0,017121921 | 2,290635452 | 1,136852835 | 4,61538258 |
| 2022 | D.pteronyssinus | 0,003125254 | 2,93129771 | 1,388327623 | 6,1891056 |
| 2022 | Plane tree | <0,0001 | 3,830645161 | 2,175502307 | 6,745036447 |
| 2022 | Anisakis | <0,0001 | 8,880486279 | 5,54648082 | 14,21857194 |
| 2022 | LTP peach | <0,0001 | 5,322128852 | 3,204480039 | 8,839204852 |
| 2022 | Hazelnut | 0,037651985 | 2,256734007 | 1,025851515 | 4,964508315 |
| 2022 | Wallnut | 0,016568059 | 2,545454545 | 1,153197837 | 5,618583935 |
| 2022 | Soy | 0,00577198 | 2,916666667 | 1,315678496 | 6,465823126 |
| 2022 | Profiline | <0,0001 | 3,646862324 | 1,952724287 | 6,810795 |
| 2023 | Rye grass | <0,0001 | 8,458545918 | 5,958840047 | 12,00686685 |
| 2023 | Cat | <0,0001 | 3,036830111 | 1,818502161 | 5,071391895 |
| 2023 | Bermuda grass | <0,0001 | 4,699380165 | 3,08051296 | 7,168992381 |
| 2023 | Dog | <0,0001 | 3,824212272 | 2,333475576 | 6,267303438 |
| 2023 | Olive pollen | 0,000456714 | 2,855392157 | 1,546459146 | 5,272214523 |
| 2023 | Alternaria | 0,006397318 | 2,281085526 | 1,240363234 | 4,1950221 |
| 2023 | Cupressus pollen | 0,002342181 | 2,831860185 | 1,40559017 | 5,705384313 |
| 2023 | Plane tree | <0,0001 | 6,489045503 | 3,81689433 | 11,03193012 |
| 2023 | Anisakis | <0,0001 | 12,56986578 | 7,974398943 | 19,81359686 |
| 2023 | LTP peach | <0,0001 | 8,764086687 | 5,281684572 | 14,54256013 |
| 2023 | Pea nut | 0,040970892 | 2,349751244 | 1,010320319 | 5,464931078 |
| 2023 | Wall nut | 0,005760879 | 2,892900857 | 1,313723138 | 6,37034937 |
| 2023 | Soy | 0,005742861 | 3,124451273 | 1,332527788 | 7,326072931 |
| 2023 | Profiline | <0,0001 | 9,07472855 | 5,268789261 | 15,6299093 |
| 2024 | Rye grass | <0,0001 | 20,44439589 | 14,08581226 | 29,67335612 |
| 2024 | Cat | <0,0001 | 6,431129477 | 3,873960629 | 10,67626398 |
| 2024 | Bermuda grass | <0,0001 | 5,589218329 | 3,680332975 | 8,488188906 |
| 2024 | Dog | <0,0001 | 9,674897119 | 5,869293207 | 15,94802491 |
| 2024 | Olive pollen | <0,0001 | 4,390289449 | 2,294360733 | 8,400876625 |
| 2024 | Alternaria | <0,0001 | 6,157757497 | 3,264463271 | 11,61537878 |
| 2024 | Cupressus pollen | <0,0001 | 11,56693548 | 4,565743391 | 29,30388001 |
| 2024 | D.pteronyssinus | 0,006190853 | 3,090889276 | 1,319968856 | 7,23774389 |
| 2024 | Plane tree | <0,0001 | 7,368212249 | 4,370264155 | 12,4227163 |
| 2024 | Anisakis | <0,0001 | 14,11825026 | 8,503097329 | 23,441457 |
| 2024 | LTP peach | <0,0001 | 76,88761468 | 36,89644612 | 160,2242468 |
| 2024 | Hazelnut | 0,013039908 | 3,057419355 | 1,208334683 | 7,736112557 |
| 2024 | Pea nut | 0,014504734 | 3,008253968 | 1,189533841 | 7,607679268 |
| 2024 | Profiline | <0,0001 | 19,42779661 | 9,531174407 | 39,60050094 |
| 2025 | Rye grass | <0,0001 | 18,99234652 | 12,67066771 | 28,46805195 |
| 2025 | Cat | <0,0001 | 4,482517483 | 2,645071112 | 7,596379125 |
| 2025 | Bermuda grass | <0,0001 | 9,725588697 | 6,082219055 | 15,55140889 |
| 2025 | Dog | <0,0001 | 8,854320988 | 5,131819846 | 15,27703671 |
| 2025 | Olea grass | <0,0001 | 5,687762605 | 2,797535171 | 11,56398096 |
| 2025 | Alternaria | <0,0001 | 7,165859564 | 3,553846205 | 14,44900548 |
| 2025 | Cupressus pollen | <0,0001 | 9,633870968 | 3,44538335 | 26,93792254 |
| 2025 | D.pteronyssinus | 0,011799871 | 2,977318548 | 1,221884742 | 7,254715144 |
| 2025 | Plane tree | <0,0001 | 7,44024024 | 4,210528725 | 13,1473215 |
| 2025 | Anisakis | <0,0001 | 14,12242991 | 7,930950812 | 25,14742951 |
| 2025 | LTP peach | <0,0001 | 42,64220183 | 19,07783082 | 95,3125853 |
| 2025 | Pea nut | 0,034561309 | 2,72 | 1,035088784 | 7,147599424 |
| 2025 | Soy | 0,00011386 | 6,116923077 | 2,146723838 | 17,42969788 |
| 2025 | Profiline | <0,0001 | 13,46440678 | 6,163049428 | 29,41567353 |
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