Concentrations of cat (Fel d1), dog (Can f1) and mite (Der f1 and Der p1) allergens in the clothing and school environment of Swedish schoolchildren with and without pets at home

Disparities in allergy and asthma prevalence among schoolteachers

BACKGROUND

Evidence suggests that school factors influence the prevalence of allergic diseases in students. However, little is known about how such factors affect the health of teachers.

OBJECTIVE

We sought to compare the prevalence of allergic and respiratory conditions among teachers from urban, suburban, and rural schools.

METHODS

Electronic survey data were collected from a random sample of prekindergarten through grade 12 teachers in Massachusetts. Comparisons were made between teacher demographics and allergic respiratory symptoms.

RESULTS

Of the 398 respondents, median (SD) age was 45 (12.32) years; 71.8% of teachers taught in suburban schools, 76.6% were female, and 87.1% were White, similar to teacher demographics collected by the Massachusetts Department of Higher Education. Although there were more female teachers, male teachers more frequently reported adverse breathing symptoms, such as wheezing (P = .007). Over half of rural teachers (54.54%) experienced respiratory symptoms such as disrupted sleep due to coughing compared to 34.61% of suburban schoolteachers (P = .03). Almost half (48.26%) of public schoolteachers experienced exercise-induced chest pain compared to 37.03% of private schoolteachers (P = .05). A higher proportion of urban schoolteachers with asthma commonly missed school as a result of food allergy compared to suburban and rural schoolteachers with asthma (P = .02). In teachers undiagnosed with asthma, associations existed between school absences and nighttime awakening due to trouble breathing (P < .0001), persistent cough (P = .002), and sore throat (P < .0001) CONCLUSIONS: Rural and public teachers reported proportionately more respiratory symptoms compared to suburban and private teachers, suggesting disparities. Future studies addressing evidence-based solutions are needed.

The Primary Prevention of Atopy: Does Early Exposure to Cats and Dogs Prevent the Development of Allergy and Asthma in Children? A Comprehensive Analysis of the Literature

The current literature shows mixed results relating to the significance of environmental exposure, such as owning a pet, and the development of atopy in children. Our review aimed to collect the most recent evidence on the association between early-life cat and dog ownership and the development of allergy and asthma. A comprehensive literature review was performed using PubMed and Scopus. The search included the main keywords of our PICO: (((early exposure) AND (children) AND (allergy)) OR (asthma)) AND (dog) OR (cat). Randomized controlled trials (RCTs), case-control studies, clinical trials, meta-analyses, and systematic reviews of children within the last five years (2018-2023) were searched and included. During the search process, 52 articles from PubMed and 43 from Scopus were found. A total of 17 articles were deemed to be suitable and included. Fairly consistent results regarding early exposure to pets, in particular dogs, and the prevention of food allergies have been described. Furthermore, there seems to be a protective effect against allergy and asthma in relation to the number of pets owned. The likelihood of a child developing allergy and asthma seems to be influenced by various factors, including the child's genetic background and early exposure to different environmental factors, including allergens that may interact with the gut microbiota and immune system.

Effects of mechanical washing and drying on the removal of pet allergens

Background: In Korea, the number of households with indoor pets is rapidly increasing in parallel with changes in cultural lifestyles. The sensitization rate of pet allergens is also increasing in Korea. Objective: We evaluated the effectiveness of washing machines to remove dog and cat hair and their allergens. In addition, this study aimed to investigate whether only a mechanical dryer without mechanical washing could be used for pet allergen removal. Method: We brushed cats and dogs, and thereafter collected their hair and used a residential vacuum cleaner to obtain dust and other particulate matter from a household. The contents of the vacuum bag were sifted through a 300-μm sieve filter. Some of the contents were placed in phosphate-buffered saline solution with 0.5% Tween 20 to make a liquid extract. Hair, dust, and liquid extract-contaminated fabric samples after mechanical washing or after drying without mechanical washing were analyzed for pet allergens (Fel d l [cat], Can f 1 [dog]) by using a two-site enzyme-linked immunosorbent assay. We assessed the remaining allergens in the contaminated fabrics after mechanical drying and washing. Results: The mean Fel d l and mean Can f 1 removal ratios after mechanical washing with detergent were > 99.99% for the dust, hair, and liquid extract. The removal ratios after mechanical washing without a detergent were lower for both Fel d 1 and Can f 1, for hair, dust, and their respective liquid extracts (p < 0.05). Mechanical drying was just as effective as mechanical washing with detergent for removing Can f 1 but was less effective for Fel d 1 (p < 0.05). Conclusion: Mechanical washing with detergent is important to remove pet allergens from contaminated fabrics. If washing is difficult, then using just a dryer without washing can be an alternative method to remove allergens from contaminated bedding or clothing.

Environmental Interventions for Asthma

Exposure and sensitization to environmental factors play a fundamental role in asthma development and is strongly associated with asthma morbidity. While hereditary factors are critical determinants of asthma, exposures to environmental factors are implicated in the phenotypic expression of asthma and have been strongly associated in the risk of its development. Significant interest has thus been geared toward potentially modifiable environmental exposures which may lead to the development of asthma. Allergen exposure, in particular indoor allergens, plays a significant role in the pathogenesis of asthma, and remediation is a primary component of asthma management. In the home, multifaceted and multitargeted environmental control strategies have been shown to reduce home exposures and improve asthma outcomes. In addition to the home environment, assessment of the school, daycare, and workplace environments of patients with asthma is necessary to ensure appropriate environmental control measures in conjunction with medical care. This article will discuss the role of the environment on asthma, review targeted environmental therapy, and examine environmental control measures to suppress environmental exposures in the home and school setting.

Work clothes as a vector for microorganisms: Accumulation, transport, and resuspension of microorganisms as demonstrated for waste collection workers

Work clothes may act as a vector for the transport of microorganisms leading to second-hand exposure; however, this has not been studied in work environments. We investigated whether microorganisms accumulate on workers' clothes in environments with elevated microbial exposures, and whether they are transported with the clothes and subsequently resuspended to the air. To study this, we selected waste collection workers and potential transport of bacteria and fungi to waste truck cabs via clothes, and compared the microbial communities within truck cabs, in waste collection workers' personal exposure, and on clean T-shirts worn by the workers. Microbial communities were also investigated for the presence of potentially harmful microorganisms. Results showed that microorganisms accumulated in large quantities (GM = 3.69 × 10⁵ CFU/m²/h for bacteria, GM = 8.29 × 10⁴ CFU/m²/h for fungi) on workers' clothes. The concentrations and species composition of airborne fungi in the truck cabs correlated significantly with the accumulation and composition of fungi on clothes and correlated to concentrations (a trend) and species composition of their personal exposures. The same patterns were not found for bacteria, indicating that work clothes to a lesser degree act as a vector for bacteria under waste collection workers' working conditions compared to fungi. Several pathogenic or allergenic microorganisms were present, e.g.: Klebsiella oxytoca, K. pneumoniae, Proteus mirabilis, Providencia rettgeri, Pseudomonas aeruginosa, and Aspergillus fumigatus, A. glaucus, A. nidulans, A. niger, and various Penicillium species. The potential 'take-home' exposure to these microorganisms are of most concern for immunocompromised or atopic individuals or people with open wounds or cuts. In conclusion, the large accumulation of microorganisms on workers' clothes combined with the overlap between fungal species for the different sample types, and the presence of pathogenic and allergenic microorganisms forms the basis for encouragement of good clothing hygiene during and post working hours.

The Indoor Environment and Childhood Asthma

PURPOSE OF REVIEW

Sensitization and exposure to triggers in the indoor environment, including aeroallergens, indoor air pollution, and environmental tobacco smoke, have a significant role in asthma development and morbidity. This review discusses indoor environmental exposures and their effect on children with asthma as well as environmental interventions and their role in improving asthma morbidity.

RECENT FINDINGS

Recent research has emphasized the role of aeroallergen sensitization and exposure in asthma morbidity and the importance of the school indoor environment. There is an established association between indoor exposures and asthma development and morbidity. Recent evidence has highlighted the importance of the indoor environment in childhood asthma, particularly the role of the school indoor environment. While home environmental interventions have had mixed results, interventions in the school environment have the potential to significantly impact the health of children, and ongoing research is needed to determine their effectiveness.

Reliability and Correlation Between Indoor Allergen Concentrations from Vacuumed Surface Samples and Electrostatic Dust Collectors

OBJECTIVES

Most studies on indoor allergen exposure used vacuumed surface samples for quantification. One alternative is electrostatic dust collectors (EDCs), which sample previously airborne settled dust. The aim of this study was to compare allergen quantification using two different sampling methods, with respect to repeatability, and to determine how well the results agree with one another.

METHODS

Four times a year, measurements were made from samples that were either collected from the vacuuming of surfaces, or from EDCs, from 20 German day-care centers totaling 167 rooms. Overall, 504 vacuumed samples collected from smooth floors, 435 samples from carpets, 291 samples from upholstered furniture and beds, and 605 EDC samples were analyzed using six fluorescence enzyme immunoassays recognizing Fel d 1, Can f 1, Mus m 1, domestic mite (DM), Dermatophagoides pteronyssinus (Dp), and Tyrophagus putrescentiae (Tp) antigens. Variances and correlations among the repeat measurements over the course of the year within each sample type, and the correlations between surface samples and the corresponding EDC samples were calculated.

RESULTS

Repeat measurements over the year correlated significantly with one another. However, only Fel d 1, Can f 1, and DM in the EDC samples; DM, Dp, Tp, and Fel d 1 in the upholstered furniture samples; and DM in the carpet samples show representative results of single measurements according to their variance ratios (within-room/between-room variance <1). The highest correlation between surface and EDC samples was found for Fel d 1 on the upholstered furniture (r 0.52), followed by Can f 1 on the upholstered furniture and Can f 1 on carpets (r 0.47 and 0.45, respectively). The maximum correlation for mite antigens was between carpet samples and EDC (DM r 0.27, Dp r 0.33). Mus m 1 and Tp antigens for the most part did not correlate to the EDC results.

CONCLUSIONS

Both vacuumed dust from upholstered furniture and EDC samples were suitable for repeatable quantification of several allergens in day-care centers within a year. However, there was little agreement among the different collection methods, especially for Mus m 1 and certain mite antigens. Therefore, the method and location used for collection may greatly influence allergen exposure assessment and study results.

The level of allergens in dust samples collected from selected schools in Shiraz, Iran and its asthma-risk implications

BACKGROUND

Both home and school are important places where children are exposed to various indoor allergens. This study aimed to identify the profile of indoor allergens in schools and its impact on asthma development.

METHODS

A total of 104 classrooms from 52 schools were selected for dust collection during the fall of 2017. The levels of indoor allergens including dust mite (Der f1, Der p1), cat (Fel d1), cockroach (Bla g1) and mouse (Mus m1) were measured by enzyme linked immunosorbent assay (ELISA). The diagnosis of asthma was made in all students of the selected classes by the allergist. The collected data were analyzed using SPSS version 21.0.

RESULTS

Out of 2816 students in the selected classes, 180 students were involved with asthma. Students were mostly exposed to Bla g1 (83.1%), followed by Der f1 (51.5%), Mus m 1 (45.5%), Der p1 (8.9%) and Fel d1 (7.9%) in the dust collected from 101 classrooms. Although levels of all studied allergens in the settled dust of the classrooms were low, there was a relationship between Fel d1 in the classroom dust and development of asthma.

CONCLUSION

This study showed considerable levels of cockroach allergens in schools. Exposure to cat allergen in our schools played an important role in asthma development; further school-based investigations require evaluating the role of classroom allergen on asthma development.

Clothing-Mediated Exposures to Chemicals and Particles

A growing body of evidence identifies clothing as an important mediator of human exposure to chemicals and particles, which may have public health significance. This paper reviews and critically assesses the state of knowledge regarding how clothing, during wear, influences exposure to molecular chemicals, abiotic particles, and biotic particles, including microbes and allergens. The underlying processes that govern the acquisition, retention, and transmission of clothing-associated contaminants and the consequences of these for subsequent exposures are explored. Chemicals of concern have been identified in clothing, including byproducts of their manufacture and chemicals that adhere to clothing during use and care. Analogously, clothing acts as a reservoir for biotic and abiotic particles acquired from occupational and environmental sources. Evidence suggests that while clothing can be protective by acting as a physical or chemical barrier, clothing-mediated exposures can be substantial in certain circumstances and may have adverse health consequences. This complex process is influenced by the type and history of the clothing; the nature of the contaminant; and by wear, care, and storage practices. Future research efforts are warranted to better quantify, predict, and control clothing-related exposures.

Clustering of conformational IgE epitopes on the major dog allergen Can f 1

Immunoglobulin E (IgE)-associated allergy affects more than 25% of the population. Can f 1 is the major dog allergen associated with respiratory symptoms but the epitopes recognized by allergic patients IgE on Can f 1 are unknown. To characterize IgE epitopes of Can f 1 recognized by dog allergic patients, six overlapping peptides spanning the Can f 1 sequence were synthesized. In direct IgE epitope mapping experiments peptides were analyzed for IgE reactivity by dot blot and Enzyme-linked immunosorbent assay (ELISA) with sera from dog allergic patients. For indirect epitope-mapping, rabbits were immunized with the peptides to generate specific IgG antibodies which were used to inhibit allergic patients’ IgE binding to Can f 1. IgE binding sites were visualized on a model of the Can f 1 three-dimensional structure. We found that Can f 1 does not contain any relevant sequential IgE epitopes. However, IgE inhibition experiments with anti-peptide specific IgGs showed that Can f 1 N- and C-terminal portion assembled a major conformational binding site. In conclusion, our study is the first to identify the major IgE epitope-containing area of the dog allergen Can f 1. This finding is important for the development of allergen-specific treatment strategies.

Association Between Allergen Exposure in Inner-City Schools and Asthma Morbidity Among Students

IMPORTANCE

Home aeroallergen exposure is associated with increased asthma morbidity in children, yet little is known about the contribution of school aeroallergen exposures to such morbidity.

OBJECTIVE

To evaluate the effect of school-specific aeroallergen exposures on asthma morbidity among students, adjusting for home exposures.

DESIGN, SETTING, AND PARTICIPANTS

The School Inner-City Asthma Study was a prospective cohort study evaluating 284 students aged 4 to 13 years with asthma who were enrolled from 37 inner-city elementary schools in the northeastern United States between March 1, 2008, and August 31, 2013. Enrolled students underwent baseline clinical evaluations before the school year started and were then observed clinically for 1 year. During that same school year, classroom and home dust samples linked to the students were collected and analyzed for common indoor aeroallergens. Associations between school aeroallergen exposure and asthma outcomes during the school year were assessed, adjusting for home exposures.

EXPOSURES

Indoor aeroallergens, including rat, mouse, cockroach, cat, dog, and dust mites, measured in dust samples collected from inner-city schools.

MAIN OUTCOMES AND MEASURES

The primary outcome was maximum days in the past 2 weeks with asthma symptoms. Secondary outcomes included well-established markers of asthma morbidity, including asthma-associated health care use and lung function, measured by forced expiratory volume in 1 second.

RESULTS

Among 284 students (median age, 8 years [interquartile range, 6-9 years]; 148 boys and 136 girls), exposure to mouse allergen was detected in 441 (99.5%) of 443 school dust samples, cat allergen in 420 samples (94.8%), and dog allergen in 366 samples (82.6%). Levels of mouse allergen in schools were significantly higher than in students' homes (median settled dust level, 0.90 vs 0.14 µg/g; P < .001). Exposure to higher levels of mouse allergen in school (comparing 75th with 25th percentile) was associated with increased odds of having an asthma symptom day (odds ratio, 1.27; 95% CI, 1.05-1.54; P = .02) and 4.0 percentage points lower predicted forced expiratory volume in 1 second (95% CI, -6.6 to -1.5; P = .002). This effect was independent of allergic sensitization. None of the other indoor aeroallergens were associated with worsening asthma outcomes.

CONCLUSIONS AND RELEVANCE

In this study of inner-city students with asthma, exposure to mouse allergen in schools was associated with increased asthma symptoms and decreased lung function. These findings demonstrate that the school environment is an important contributor to childhood asthma morbidity. Future school-based environmental interventions may be beneficial for this important public health problem.

Cat (Fel d 1) and dog (Can f 1) allergen levels in cars, dwellings and schools

Pets are an important source of indoor allergens. The aim of the study was to compare cat and dog allergen levels in cars, schools and homes. The study was carried out in 17 cars, 14 classrooms and 19 dwellings located in the highly industrialized and urbanized region of Poland. Dust and air samples were analyzed for Fel d 1 and Can f 1 using a double monoclonal ELISA assay. The highest amounts of cat and dog allergens (Fel d 1: 1169 μg/g; Can f 1: 277 μg/g) were found in dwellings with pets. Allergen concentrations were correlated with the number of animals kept at home. Although concentrations on automobile seats were lower, Fel d 1 levels exceeded 8 μg/g in 23.5 % of cars and high levels of Can f 1 (>10 μg/g) were found in 17.6 % of cars. The study revealed that cars of pet owners may be reservoirs of cat and dog allergens even when animals are not transported in them. In schools, concentrations of pet allergens did not reach high levels, but the moderate levels of Fel d 1 (≥1-8 μg/g) and Can f 1 (≥2-10 μg/g) were detected in 42.9 and 7.1 % of the investigated classrooms. Concentrations of cat and dog allergen in schools were higher than in homes without pets. While airborne Fel d 1 and Can f 1 levels were found low, residential allergen concentrations in settled dust and air were correlated. The study results suggest that classrooms and cars of pet owners may be important sites of exposure to cat and dog allergens, though the highest concentrations of Fel d 1 and Can f 1 are found in homes of pet owners.

Allergen quantification in surface dust samples from German day care centers

Indoor allergens are among the main causes of allergic rhinitis and asthma. Allergen exposure is not limited to private homes. Mite, cat, and dog allergens were measured in day care centers to determine whether these concentrations detected might exert significant influence on human health. In 20 day care centers across North Rhine-Westphalia, Germany, the surfaces of 171 rooms were vacuumed 4 times a year to collect dust (1340 samples in total). In all samples, domestic mite antigens (DM) and the main allergens of cats (Fel d 1) and dogs (Can f 1) were quantified using enzyme immunoassays. Provisional threshold limits (PTL) for increased risks of sensitization and allergic symptoms were estimated according to published values and conversion factors. The influence of room characteristics on allergen concentrations was analyzed in mixed linear models, also considering values below the limit of detection (LOD). Nearly all samples contained allergens (99% DM, 96% Fel d 1, and 96% Can f 1). The concentrations rarely exceeded levels that were previously found to induce symptoms in home environments, but were frequently higher than estimates for enhanced sensitization risk (13% DM, 43% Fel d 1, and 27% Can f 1). Upholstered furnishings had the highest dust and allergen loads, followed by carpets and smooth floors. Allergen concentrations on different surface types that were sampled in the same room at the same time were significantly correlated and analyzed in separate models. The highest DM concentrations were present in bedrooms and in autumn. Further, DM loads on floors decreased significantly in rooms that were renovated within the last 5 years. If there were no records that furnishings were vacuumed, there were then significantly higher Can f 1 loads. Sweeping floors elevated DM and cat allergen concentrations. In addition to mite allergens, cat and dog allergens were detected in nearly all samples from day care centers. Overall, the present results indicate that allergen concentrations may be reduced by renovation and appropriate cleaning procedures.

Measurement of aeroallergens from furnace filters

BACKGROUND

Exposure assessment is an important component of allergic disease diagnosis and management. Analysis for allergen content in vacuumed dust has been used traditionally.

OBJECTIVE

To study allergen levels of dust taken from high-efficiency furnace filters in Midwestern homes.

METHODS

Furnace filters used were FQT12 1-inch disposable filters with high-efficiency media placed in homes enrolled in the Kansas City Safe and Healthy Homes Project. Dust was removed from the filters by vacuuming. Fungal culture was used to obtain counts of viable spores. Aeroallergens Fel d1, Can f1, Mus m1, Der f1, Der p1, and Bla g2 and antigenic material from Alternaria, Aspergillus, Cladosporium, and Penicillium species were measured using commercially available immunoassay materials.

RESULTS

Sixty filters were recovered from 56 homes after an average 135 days in situ. Mean weight of dust recovered was 2.43 g and correlated well with the time the filter was in place. Viable spore counts ranged to 4.8 × 10(7) per gram of dust. Mean fungal antigenic material ranged to 42 μg per gram for Cladosporium species. Mean aeroallergen material ranged to 7 μg per gram for Fel d1. Aeroallergen measurements were above the level of detection in 100% of houses for Fel d1 and 89% of houses for Bla g2. Levels of Fel d1 and Can f1 were strongly positively correlated.

CONCLUSION

Allergens from 5 common aeroallergen species and antigenic material from 4 common fungal taxa can be measured in dust taken from high-efficiency furnace filters.

Allergens on desktop surfaces in preschools and elementary schools of urban children with asthma

Desktop dust has been studied as a source of food allergen, but not as a source of potential aeroallergen exposure. Thirty-six wiped samples from desktop surfaces were collected from preschools and schools. Samples were analyzed for detectable levels of common aeroallergens including Alternaria, cockroach, dog, dust mite, cat, mouse, and rat allergens by immunoassay. Mouse allergen was the most prevalent, detectable in 97.2% of samples. Cat allergen was detectable in 80.6% of samples, and dog allergen was detectable in 77.8% of samples. Other allergens were not as prevalent. Mouse was the only allergen that was highly correlated with settled floor dust collected from the same rooms (r = 0.721, P < 0.001). This is the first study to detect aeroallergens on desktop surfaces by using moist wipes. Allergens for mouse, cat, and dog were highly detectable in wipes with mouse desktop surface levels correlating with levels in vacuumed floor dust.

Animal allergens and their presence in the environment

Exposure to animal allergens is a major risk factor for sensitization and allergic diseases. Besides mites and cockroaches, the most important animal allergens are derived from mammals. Cat and dog allergies affect the general population; whereas, allergies to rodents or cattle is an occupational problem. Exposure to animal allergens is not limited to direct contact to animals. Based on their aerodynamic properties, mammalian allergens easily become airborne, attach to clothing and hair, and can be spread from one environment to another. For example, the major cat allergen Fel d 1 was frequently found in homes without pets and in public buildings, including schools, day-care centers, and hospitals. Allergen concentrations in a particular environment showed high variability depending on numerous factors. Assessment of allergen exposure levels is a stepwise process that involves dust collection, allergen quantification, and data analysis. Whereas a number of different dust sampling strategies are used, ELISA assays have prevailed in the last years as the standard technique for quantification of allergen concentrations. This review focuses on allergens arising from domestic, farm, and laboratory animals and describes the ubiquity of mammalian allergens in the human environment. It includes an overview of exposure assessment studies carried out in different indoor settings (homes, schools, workplaces) using numerous sampling and analytical methods and summarizes significant factors influencing exposure levels. However, methodological differences among studies have contributed to the variability of the findings and make comparisons between studies difficult. Therefore, a general standardization of methods is needed and recommended.

Animal allergens and their presence in the environment

Exposure to animal allergens is a major risk factor for sensitization and allergic diseases. Besides mites and cockroaches, the most important animal allergens are derived from mammals. Cat and dog allergies affect the general population; whereas, allergies to rodents or cattle is an occupational problem. Exposure to animal allergens is not limited to direct contact to animals. Based on their aerodynamic properties, mammalian allergens easily become airborne, attach to clothing and hair, and can be spread from one environment to another. For example, the major cat allergen Fel d 1 was frequently found in homes without pets and in public buildings, including schools, day-care centers, and hospitals. Allergen concentrations in a particular environment showed high variability depending on numerous factors. Assessment of allergen exposure levels is a stepwise process that involves dust collection, allergen quantification, and data analysis. Whereas a number of different dust sampling strategies are used, ELISA assays have prevailed in the last years as the standard technique for quantification of allergen concentrations. This review focuses on allergens arising from domestic, farm, and laboratory animals and describes the ubiquity of mammalian allergens in the human environment. It includes an overview of exposure assessment studies carried out in different indoor settings (homes, schools, workplaces) using numerous sampling and analytical methods and summarizes significant factors influencing exposure levels. However, methodological differences among studies have contributed to the variability of the findings and make comparisons between studies difficult. Therefore, a general standardization of methods is needed and recommended.

Allergens and β-glucans in dutch homes and schools: characterizing airborne levels

Background

Indoor air quality has an effect on respiratory health. Children are more vulnerable to a decreased indoor air quality as their lungs are still developing. We measured levels of allergens and β-(1,3)-glucans in 19 school buildings and determined whether measured levels could be reproduced. School levels were compared to those in 169 homes and the effect of building characteristics on both home and school exposure was explored.

Methods

Electrostatic Dust fall Collectors were placed in school buildings for 8 weeks and in homes for 2 weeks to collect settled airborne dust. Cat, dog, and mouse allergen levels, domestic mite antigen levels and β-(1,3)-glucans were measured in the extracts from the collectors. Results were corrected for sampling duration. Using questionnaire data, relations between measured levels and building and classroom characteristics were explored.

Results

In schools, exposure levels were highest in classrooms and were influenced by the socioeconomic status of the children, the season measurements were performed, moisture status of the building and pet ownership. Repeated measurements in different seasons and over the years showed significantly different levels. Home exposure was influenced by socioeconomic status, occupancy and pet ownership. Domestic mite antigen was found in higher levels in extracts from homes compared to schools while pet allergen levels were 13 times higher in schools compared to homes without pets. For mouse allergen overall levels of exposure were low but still two times higher in schools compared to homes. Levels of β-(1,3)-glucans were also approximately two times higher in schools than in homes.

Conclusion

Exposure levels of several allergens and β-(1,3)-glucans in schools differ over time and are higher than in homes. For children, exposure levels measured at school could contribute to their total exposure as especially animal allergen levels can be much higher in schools compared to homes.

Rapid allergen inactivation using atmospheric pressure cold plasma

Allergies have become a global problem, and effective control is greatly needed. Here, the inactivation effects of the atmospheric pressure cold plasma (APCP) on aerosolized allergens including Der p 1, Der f 1, Asp f 1, Alt a 1, and Can f 1 as well as those from indoor and outdoor environments were investigated. The effectiveness of the APCP treatment was further studied using blood sera from the allergen sensitized humans. In addition, the allergen samples were also analyzed using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Results revealed that the APCP was highly effective in reducing the allergenicity of both lab-prepared and environmental allergen aerosols. The airborne reductions were shown to range from 30% for Der p 1 to 80% for Can f 1 allergen for 0.12 s exposure. Allergnicity tests showed that the APCP treated Asp f 1 allergens caused 50% less binding with IgEs in the blood sera compared to the control. The observed allergenicity loss was due to hydroxyl radicals produced by the plasma device. The results from SDS-PAGE showed that the plasma treatment resulted in decreased size of the Asp f 1 allergen. The developed technology holds great promise in combating the allergic diseases.

A nationwide survey of inhalant allergens sensitization and levels of indoor major allergens in Korea

PURPOSE

The higher prevalence of respiratory allergic disease may be due to increased exposure to inhalation allergens. We conducted a survey of allergic diseases in autumn and winter with detection of major indoor allergens in major cities in Korea.

METHODS

We enrolled 110 subjects from the fourth Korea National Health and Nutrition Examination Survey with stratified, cluster, and systematic sampling procedures. All participants answered a health questionnaire as well as underwent a skin prick test (SPT) and ImmunoCAP for 11 indoor major allergens. We also measured the levels of 5 major allergens (Der f 1, Der p 1, Can f 1, Bla g 1, and Asp f 1) in fine indoor dust from the houses of 60 subjects with a 2-site ELISA.

RESULTS

The prevalence of allergic rhinitis and asthma were 25.5% and 7.3%, respectively. The most common sensitized allergens identified by SPT and ImmunoCAP were Dermatophagoides farinae (40.9%, 36.8%), followed by cockroach (23.6%, 19.5%), mugwort (13.6%, 22.9%), oak (9.1%, 22.9%), Japanese hop (9.1%, 8.6%), and dog dander (8.2%, 6.9%). There was a modest discrepancy between SPT and ImmunoCAP. Der f 1 and Der p 1 were detected in 91.7% and 45.0% of the enrolled houses, respectively. Der f 1 indicated high concentrations in all specific provinces in Korea; however, Der p 1 measured high only in the south. Dog dander allergens were present in 71.7% of houses; however, Bla g 1 was present in only 11.7% of houses and Asp f 1 was not detected in any houses.

CONCLUSIONS

The most important inhalant allergens in Korea are house dust mites followed by cockroach, mugwort, oak, Japanese hop, and dog dander in indoor environment, in which The dominant species of house dust mites were different according to region.

Cat and dog sensitization in pet shop workers

BACKGROUND

Sensitivity and symptoms related to animal proteins have been investigated in various occupational groups. However, data from pet shops are limited.

AIMS

To investigate rates of sensitivity to cats and dogs among pet shop workers, to assess the relationship between sensitivity, allergen levels and symptoms and to investigate whether passive transport from pet shops to homes is possible.

METHODS

Pet shop workers underwent interviews with a questionnaire adapted from the European Community Respiratory Health Survey. Dust samples for allergen detection were collected from pet shops using a vacuum cleaner. Skin tests were performed with common allergens. Dust samples were also obtained from the houses of 7 workers and 12 control subjects.

RESULTS

Fifty-one workers from 20 pet shops were included in the study. Thirteen (25%) workers reported work-related symptoms. Four workers had sensitivity to animal allergens. The mean cat/dog allergen levels from pet shops were 15.7 and 3.2 µg/g, respectively. There was no significant relationship between cat/dog allergen levels and work-related symptoms and sensitivity to pets. None of the dust samples collected from the homes of pet shop workers contained cat allergens. Dog allergen was detected in only one house (0.58 µg/g). Neither cat nor dog allergens were found in the homes of the 12 control subjects.

CONCLUSIONS

Although a quarter of pet shop workers reported work-related symptoms, sensitivity to cat and dog was low. These findings suggest that work-related symptoms may be due to other factors than cat and dog sensitivity.

Controversial role of pets in the development of atopy in children

BACKGROUND

Exposure to environmental allergens originating from different sources has been implicated in the sensitization to the respective allergens and development of atopic diseases. Keeping domestic animals is associated with exposure to relevant allergens but there are controversial data whether this exposure promotes or protects from the development of atopy.

DATA SOURCES

We herein reviewed the literature regarding the available data for the exposure to pets (cats and/or dogs) and the development of atopy. For this purpose, we searched the PubMed database.

RESULTS

This review attempts to answer the following questions that arise from the daily practice and the relevant studies, which are: a) is pet keeping associated with sensitization? b) is there an association between keeping pets and the development of asthma, allergic rhinitis and eczema, and, c) what is the underlying mechanism of any possible protective association? Despite the fact that several studies and meta-analyses have been conducted to explore the role of pets in the development of atopy, there are still conflicting pieces of evidence. It seems that there are different effects depending on the type of pets, the time and duration of exposure, and the genetic background of the individual.

CONCLUSION

Further appropriately designed birth cohort studies are needed to explore whether exposure to relevant allergens from pets promotes or protects from the development of atopy.

Airborne allergens, endotoxins, and particulate matter in elementary schools, results from Germany (LUPE 2)

Allergic disorders are the most common childhood-related chronic diseases in developed countries. It is essential to assess the exposure, especially in schools, where children spend a large portion of their time. We aimed to investigate allergen and endotoxin levels in the air of schools and to observe seasonal variations of these factors. We evaluated airborne concentrations of house dust mites allergens (Der p 1, Der f 1), cat allergen (Fel d 1), and endotoxin in PM10 in 14 classrooms during the school days in the region of Munich, each over 20 consecutive days and in 1 classroom over the course of a year (at 83 days); we also tested outdoor air close to the schools. Endotoxin levels were quantified using two different analytical methods. In addition, indoor air climate parameters were measured. The median daily indoor CO2 and PM10 concentrations in the classrooms ranged from 423 to 3,135 ppm (median: 1,211 ppm) and 9 to 390 μg/m(3) (median: 127 μg/m(3)), respectively. Fel d 1 in the PM10 samples was the most frequently detected allergen, with levels from 0.02 to 1.15 ng/m(3) in a total of 301 samples (median: 0.19 ng/m(3), 95th percentile: 0.57 ng/m(3)). Der p 1 and Der f 1 were detected in only 51% and 19% of the samples, with 95th percentiles at 0.5 and 0.3 ng/m(3). Endotoxin levels in the PM10 and inhalable dust samples ranged from 0.5 to 84.1 EU/m(3) (median: 15.3 EU/m(3); 95th percentile: 58.2 EU/m(3)) and from 0.03 to 115 EU/m(3) (median: 8.4 EU/m(3); 95th percentile: 27.9 EU/m(3)). Fel d 1 and endotoxin were found in higher levels in the winter months. The results of the two different indoor sampling techniques for endotoxin were statistically significantly correlated. The results of airborne allergens indicate a generally low exposure level in classrooms. With regard to endotoxin, our study showed higher levels in schools compared with residences.

Allergens in urban schools and homes of children with asthma

BACKGROUND

Most studies of indoor allergens have focused on the home environment. However, schools may be an important site of allergen exposure for children with asthma. We compared school allergen exposure to home exposure in a cohort of children with asthma. Correlations between settled dust and airborne allergen levels in classrooms were examined.

METHODS

Settled dust and airborne samples from 12 inner-city schools were analyzed for indoor allergens using multiplex array technology (MARIA). School samples were linked to students with asthma enrolled in the School Inner-City Asthma Study (SICAS). Settled dust samples from students' bedrooms were analyzed similarly.

RESULTS

From schools, 229 settled dust and 197 airborne samples were obtained. From homes, 118 settled dust samples were obtained. Linear mixed regression models of log-transformed variables showed significantly higher settled dust levels of mouse, cat and dog allergens in schools than homes (545% higher for Mus m 1, estimated absolute difference 0.55 μg/g, p < 0.0001; 198% higher for Fel d 1, estimated absolute difference 0.13 μg/g, p = 0.0033; and 144% higher for Can f 1, estimated absolute difference 0.05 μg/g, p = 0.0008). Airborne and settled dust Mus m 1 levels in classrooms were moderately correlated (r = 0.48; p < 0.0001). There were undetectable to very low levels of cockroach and dust mite allergens in both homes and schools.

CONCLUSION

Mouse allergen levels in schools were substantial. In general, cat and dog allergen levels were low, but detectable, and were higher in schools. Aerosolization of mouse allergen in classrooms may be a significant exposure for students. Further studies are needed to evaluate the effect of indoor allergen exposure in schools on asthma morbidity in students with asthma.

Poor air quality in classrooms related to asthma and rhinitis in primary schoolchildren of the French 6 Cities Study

Background

Relationships between indoor air quality (IAQ) found in schools and the allergic and respiratory health of schoolchildren have been insufficiently explored. A survey was conducted in a large sample of classrooms of primary schools in France to provide objective assessments of IAQ to which young schoolchildren are exposed in classrooms, and to relate exposure to major air pollutants found in classrooms to asthma and allergies of schoolchildren.

Methods

Concentrations of fine particles with aerodynamic diameter ≤2.5 μm (PM_2.5), nitrogen dioxide (NO₂) and three aldehydes were objectively assessed in 401 randomly chosen classrooms in 108 primary schools attended by 6590 children (mean age 10.4 years, SD ±0.7) in the French 6 Cities Study. The survey incorporated a medical visit including skin prick testing (SPT) for common allergens, a test for screening exercise-induced asthma (EIA) and a standardised health questionnaire completed by parents.

Results

Children were differently exposed to poor air quality in classrooms, with almost 30% being highly exposed according to available standards. After adjusting for confounders, past year rhinoconjunctivitis was significantly associated with high levels of formaldehyde in classrooms (OR 1.19; 95% CI 1.04 to 1.36). Additionally, an increased prevalence of past year asthma was found in the classrooms with high levels of PM_2.5 (OR 1.21; 95% CI 1.05 to 1.39), acrolein (OR 1.22; 95% CI 1.09 to 1.38) and NO₂ (OR 1.16; 95% CI 0.95 to 1.41) compared with others. The relationship was observed mostly for allergic asthma as defined using SPT. A significant positive correlation was found between EIA and the levels of PM_2.5 and acrolein in the same week.

Conclusions

In this random sample, air quality in classrooms was poor, varied significantly among schools and cities, and was related to an increased prevalence of clinical manifestations of asthma and rhinitis in schoolchildren. Children with a background of allergies seemed at increased risk.

A children's asthma education program: Roaring Adventures of Puff (RAP), improves quality of life

BACKGROUND

It is postulated that children with asthma who receive an interactive, comprehensive education program would improve their quality of life, asthma management and asthma control compared with children receiving usual care.

OBJECTIVE

To assess the feasibility and impact of 'Roaring Adventures of Puff' (RAP), a six-week childhood asthma education program administered by health professionals in schools.

METHODS

Thirty-four schools from three health regions in Alberta were randomly assigned to receive either the RAP asthma program (intervention group) or usual care (control group). Baseline measurements from parent and child were taken before the intervention, and at six and 12 months.

RESULTS

The intervention group had more smoke exposure at baseline. Participants lost to follow-up had more asthma symptoms. Improvements were significantly greater in the RAP intervention group from baseline to six months than in the control group in terms of parent's perceived understanding and ability to cope with and control asthma, and overall quality of life (P<0.05). On follow-up, doctor visits were reduced in the control group.

CONCLUSION

A multilevel, comprehensive, school-based asthma program is feasible, and modestly improved asthma management and quality of life outcomes. An interactive group education program offered to children with asthma at their school has merit as a practical, cost-effective, peer-supportive approach to improve health outcomes.

Domestic exposure to aeroallergens in Hong Kong families with asthmatic children

Indoor aeroallergen exposures increased asthma symptoms in Caucasians, but their determinants and relationship to asthma and allergy in Asians are unclear. This study investigated exposures to cat, cockroach, and Blomia tropicalis allergens in 115 Hong Kong families with asthmatic children. Patients underwent exhaled nitric oxide and spirometric measurements. Home visits were made within 2 weeks during which parents completed a standardized questionnaire. Fel d 1, Bla g 2, and Blo t 5 in dust samples collected from patients' mattresses, bedroom floors, and living room floors were measured by immunoassays. These aeroallergens were only detectable in some homes (38-55% for Fel d 1; 9-21% for Bla g 2, and 7-14% for Blo t 5). The presence of cat and/or dog was a strong determinant for Fel d 1 in all indoor sites. The timing and frequency of bedding change was associated with Bla g 2 levels, whereas the timing of bedroom floor cleaning was a consistent factor for Blo t 5 levels. Asthmatic children in families with high allergen exposure were more likely to have ≥4 wheezing attacks in preceding 12 months and exercise-induced wheezing than those with normal allergen exposure (P = 0.051 and 0.030, respectively). Mattress levels of all three allergens were also associated with severity of several allergy symptoms (P = 0.025-0.005). None of these aeroallergens correlated with exhaled nitric oxide and spirometric parameters. This study identifies determinants for cat, cockroach, and B. tropicalis levels in Hong Kong families with asthmatic children. These exposures are associated with severity of allergy symptoms.

Fungal DNA and pet allergen levels in Swedish day care centers and associations with building characteristics

Pet allergens and mold growth related to damp are common phenomena in day care centers in Sweden but exposure measurements of these factors are lacking. The aim of this study was to investigate the relationship between building construction and indoor environment quality in Swedish day care centers and the potential for exposure to fungi (analyzed by quantitative PCR) and animal allergens (analyzed by ELISA). Measurements were performed in 21 day care centers (103 rooms) from one municipality in Sweden, which were identified as constructions at risk of dampness (85% of the buildings) and with visible damage and mold growth (54% of the buildings). Dust samples were collected using cotton swab and Petri dishes. Total fungal DNA was detected in 99% and 100%, Aspergillus/Penicillium DNA in 54% and 68%, and Stachybotrys chartarum DNA in 4% and 9% of the investigated rooms in cotton swab and Petri dish samples, respectively. The total fungal DNA levels (Geometric Mean, GM) were 4.2 × 10(6) cell equivalents per m(2) and 2.9 × 10(5) cell equivalents per m(2) per day in the swab and Petri dish samples, respectively. The concentrations (GM) of cat (Fel d1), dog (Can f1), and horse (Equ cx) allergens were 9.4, 7.2 ng m(-2) day(-1), and 5.0 unit per m(2) per day, respectively. Total fungal DNA levels were higher in risk construction buildings (p = 0.01), in rooms with linoleum flooring material (p = 0.003), and in buildings with rotating heat exchangers (p = 0.02). There were associations between total fungal DNA levels and cat (p = 0.02), dog (p < 0.001), and horse (p = 0.001) allergens. In conclusion, risk constructions, damp constructions, mould growth, fungal DNA, and animal allergens were common exposure factors in Swedish day care centers. Building constructions that represent a high risk for internal dampness should be avoided in the future, and measures to reduce allergen levels should be considered to protect pet-allergic children from asthmatic problems.

The management of the allergic child at school: EAACI/GA2LEN Task Force on the allergic child at school

Allergy affects at least one-quarter of European schoolchildren, it reduces quality of life and may impair school performance; there is a risk of severe reactions and, in rare cases, death. Allergy is a multi-system disorder, and children often have several co-existing diseases, i.e. allergic rhinitis, asthma, eczema and food allergy. Severe food allergy reactions may occur for the first time at school, and overall 20% of food allergy reactions occur in schools. Up to two-thirds of schools have at least one child at risk of anaphylaxis but many are poorly prepared. A cooperative partnership between doctors, community and school nurses, school staff, parents and the child is necessary to ensure allergic children are protected. Schools and doctors should adopt a comprehensive approach to allergy training, ensuring that all staff can prevent, recognize and initiate treatment of allergic reactions.

Cat sensitization identified by recombinant Fel d 1 several years before symptoms--results from the BAMSE cohort

Exposure to cat is one of the most important causes of allergic disease. The objective of this study was to investigate IgE reactivity to the recombinant major cat allergen, rFel d 1, as an early marker of cat sensitization. Based on questionnaires, 144 children with allergic symptoms due to cat, or where such symptoms were suspected, were selected from the birth cohort BAMSE and allocated into three study groups. Blood samples taken at age 4 and 8 yrs were analysed for IgE to rFel d 1 and cat dander extract (CDE) by quantitative ELISA (cut-off limit 0.037 kU(A)/l) and the ImmunoCAP System (cut-off limit 0.35 kU(A)/l), respectively. At 4 yrs, 25/33 children with certain allergic symptoms to cat had IgE to both rFel d 1 and CDE, while 14/42 of those suspecting symptoms at 4 had IgE to rFel d 1 and 9/42 to CDE. In a group developing symptoms after 4 yrs, 60/69 had IgE to rFel d 1 and 57/69 to CDE at 8, while 33/69 had IgE to rFel d 1 already at 4 and 26/69 to CDE. This was the only one of the three study groups where a significant increase in the IgE levels to rFel d 1 was found from 4 to 8 yrs (p < 0.001), even when only children with IgE to rFel d 1 already at 4 were included (p < 0.001). We show that the single major cat allergen rFel d 1 is at least as good as CDE in the diagnosis of cat allergy in childhood. With a sensitive rFel d 1 assay cat sensitization can be detected several years before symptoms to cat are reported.

Indoor allergens in Minnesota schools and child care centers

Elevated concentrations of allergens in the indoor environment may cause allergic sensitization and symptoms. Occupant exposure to indoor allergens in educational facilities should and can be controlled. This study (1) assessed the presence of indoor allergens in Minnesota schools and child care centers, (2) characterized the distribution of allergens in different materials, and (3) evaluated the effect of building and maintenance interventions on allergen concentrations. Settled dust samples were collected from carpet, vinyl tile floors, and upholstered furniture in six schools and seven child care centers before and after interventions. Interventions included changes to cleaning, ventilation, entry mats, furnishings, flooring, and classroom items. The amount of total dust, culturable fungi, and indoor allergens--cockroach, dust mite, cat, and dog--were quantified in the dust samples. Cockroach and dust mite allergens were generally low and below the detection limit, but one dust mite allergen was detected in some areas. Cat and dog allergens were frequently detected at elevated levels, with half the samples above the provisional sensitization risk thresholds and a few samples above the symptom thresholds. Allergen concentrations were highest in upholstered furniture, followed by carpeting and then vinyl floor tile. Cat and dog allergens were lower after the interventions. Cat and dog allergens, but not dust mite and cockroach allergens, seem to be ubiquitous in child care and elementary schools of the U.S. Midwest. These allergens may contribute to sensitization in atopic individuals and occasionally cause symptoms in sensitized allergic individuals. Fleecy materials that are not adequately cleaned, such as upholstered furniture, appear to be the most significant allergen reservoirs. Modest environmental interventions can be implemented by building staff, which should result in lower allergen concentrations.

Indoor allergens in school and day care environments

Most studies that have examined exposure to indoor allergens have focused on home environments. However, allergen exposures can be encountered in environments other than the home. For example, many children spend a large part of their time in schools and day care facilities. Over the past 2 decades, a large number of studies have been conducted in school and day care environments. However, the role of indoor exposures in allergy and asthma development or morbidity in these settings is not well characterized. The purpose of this review is to evaluate the importance of indoor allergen exposures in school and day care settings. We summarize the key findings from recent scientific literature, describe exposure characteristics, discuss the role of these exposures in relation to asthma and allergy symptoms, and provide information on the effectiveness of published interventions.

Mouse allergens in urban elementary schools and homes of children with asthma

BACKGROUND

The association between allergens in schools and childhood asthma has not been well studied, particularly in the United States.

OBJECTIVE

To investigate allergen exposure in schools compared with homes with a specific focus on children with asthma.

METHODS

Dust samples were collected from 46 rooms in 4 urban elementary schools (northeastern United States) and from 38 student bedrooms. Samples were analyzed for cat (Fel d 1), dog (Can f 1), cockroach (Bla g 2), dust mites (Der f 1/Der p 1), and mouse urinary protein (MUP). Questionnaires identified students with physician-diagnosed asthma.

RESULTS

Cat and dog allergens were detectable in most school samples (96% and 78%, respectively), but at low levels. Cockroach allergen was detectable in only 11% of school samples. Mouse allergen was detectable in 89% of school samples, with 68% having MUP levels greater than 0.5 microg/g. In contrast, MUP was detectable in only 26% of bedroom samples. Matched classroom and home samples from 23 asthmatic students showed higher geometric mean MUP levels in the classroom vs the home (6.45 microg/g vs 0.44 microg/g, P < .001). However, there were lower geometric mean dust mite (Der f 1) levels in the classroom vs the home (0.04 microg/g vs 0.66 microg/g, P < .001).

CONCLUSIONS

There are significantly higher levels of MUP but lower levels of Der f 1 in schools vs homes. It is important to recognize that children with asthma may encounter varying levels of allergens in environments outside the home, such as schools.

Parent report of pests and pets and indoor allergen levels in inner-city homes

BACKGROUND

Guidelines recommend allergen avoidance for patients with allergic asthma, but direct measurements of home allergen levels are not available to most physicians. Parent report of indoor allergen exposure is a potentially convenient and inexpensive surrogate measure of exposure, although validity of parent report to estimate indoor allergen levels is not well established.

OBJECTIVE

To determine if parent-reported pest and pet exposures can identify patients with clinically relevant allergen exposure.

METHODS

Parents of 300 inner-city children completed a survey about pests (cockroaches and mice) and furred pets (dogs and cats). Settled dust samples were obtained for Bla g 1, Mus m 1, Can f 1, and Fel d 1 from kitchens and bedrooms.

RESULTS

Parent reports were associated with clinically relevant levels of Bla g 1, Mus m 1, Can f 1, and Fel d 1 (P < .001 for all). For example, when parents reported cockroaches were present, 86% of homes had settled dust Bla g 1 levels of 1 U/g or higher, and when they reported mice were present, 90% had Mus m 1 levels greater than 500 ng/g. Report of pets was also predictive of clinically meaningful allergen levels. Parent-reported absence of pets provided assurance that allergen levels were below relevant thresholds (negative predictive value, 80%-98%). However, parent-reported absence of pests did not provide assurance of low levels of these allergens (negative predictive value, 38%-75%).

CONCLUSIONS

Since direct measurement of indoor allergens is not always feasible, especially in the inner city, parent report of pests and pets may be sufficient to recommend environmental control practices for sensitized children. Negative parent reports of pests are not sufficient evidence of low pest allergen exposure.

House dust mites on skin, clothes, and bedding of atopic dermatitis patients

BACKGROUND

Atopic dermatitis is a common allergic condition in children, often associated with a positive skin reaction to house dust mite allergens.

AIM

To determine the presence of house dust mites on the skin, clothes, and bedding of patients with atopic dermatitis.

METHODS

Nineteen patients with atopic dermatitis were examined during a 2-year period. Samples from affected and healthy skin surfaces were obtained with adhesive tape, and dust samples from bedding and clothes were collected with a vacuum cleaner at the start of the study and 3-6 weeks later, and examined for the presence of house dust mites. The findings were compared with those of 21 healthy controls.

RESULTS

The most common mite species on skin were Dermatophagoides pteronyssinus and Dermatophagoides farinae, which were found in nine patients and three controls. The patient group showed a significantly larger percentage of samples with mites than did the control group (34.9% and 7.9%, respectively) (P < 0.001), and a significantly larger percentage of individuals with at least one positive sample (84.2% and 14.2%, respectively) (P < 0.0001). No correlation was found between the number of mites on the skin and clothes/bedding of patients, or between patients and controls with regard to the number of mites on the clothes and bedding.

CONCLUSIONS

Patients with atopic dermatitis showed a higher prevalence of mites on their skin than did healthy individuals, which could be involved in allergic sensitization and disease exacerbation.

Asthma counselling targeted to removal of domestic animals

OBJECTIVES

To create and evaluate the efficacy of a short individualized educational intervention program, based on Prochaska's transtheoretical model, for a six-month period in a population of adult asthma patients living with domestic animals but sensitized to these pets.

METHODS

A randomized, controlled study using a pretested questionnaire was conducted at three different times (pretest, and at three and six months postintervention).

RESULTS

Eleven members (29%) of the intervention group and eight members (21%) of the control group removed their pets within six months (X(2)=3.23; P>0.35). The two groups showed similar improvements in their perception of the benefits of pet removal and in their level of belief that they could do it. The experimental group showed a greater improvement in knowledge acquisition about asthma and allergies than the control group (P<0.05). Both experimental and standard educational interventions were effective in facilitating progression through the stages of behavioural change.

CONCLUSION

Overall, the results do not support the utility of behavioural change educational intervention, tailored to the transtheoretical model stage of the individual, in the context of convincing patients to remove their pets from their homes. However, the decision-making aid appears to be helpful in raising awareness of the problem of asthma and allergy in the patient, and in developing appropriate knowledge.

Validity of the interview on pets kept at home for predicting the actual domestic expsoure to their specific allergens. Krakow inner city area study

The aim of the study was to describe the exposure to dog (Can f 1) and cat (Fel d 1) allergens within homes of very young children living with and without pets, and to assess the validity of the interview on pets for predicting the actual exposure to pet allergens in house dust. House dust samples were collected in 275 dwellings from the mattresses, children’s bedroom and kitchen floors. In the laboratory, dust samples were analyzed for Can f 1 and Fel d 1 using monoclonal antibody enzyme-linked immunosorbent assays (ELISA). The majority of households (79.3%) had neither a dog nor a cat living in the home over the past 6 months preceding the survey. Dog allergen above 2 μg/g dust were found in 22.5% of homes and 14.2% of homes contained dog allergen above 10 μg/g of house dust. In the total study sample, cat allergen above 1 μg/g of dust were found in 12.7% of homes, and 3.3% of homes contained Fel d 1 levels greater than 8 μg/g of dust. The majority of children (75.0%) with reported ownership of dogs were exposed to Can f 1 levels above 2 μg/g of house dust, and 73.1% of children with cats at home were exposed to Fel d 1 concentrations above 1 μg/g house dust. The results of the study showed that post-test probability of the true exposure to Can f 1 above 2 μg/g dust in houses with positive interview on indoor dogs was 75.0% (95%CI: 61.7–84.8%). On the other hand, the prediction of exposure estimated from the interview data on indoor dogs produced 12.6% of false negatives (95% CI: 9.9–15.8%). Similarly, the post-test probability of the true exposure to Fel d 1 above 1 μg/g dust in houses with positive interview on indoor cats was 73.1% (95%CI: 55.1–85.7%). On the other hand, the interview data produced 6.4% false negatives (95% CI: 4.6–9.0%). In conclusion, the study demonstrated that homes in Poland with pet ownership are important reservoir of Can f 1 and Fel d 1 allergens with levels that might induce allergic symptoms. Even in homes of children without a dog or cat indoors, there was a higher prevalence of pet allergens at the levels above allergic sensitisation thresholds. This may have an important implication for epidemiologic studies on pet related allergy and prevention practice.

Classroom aeroallergen exposure in Arkansas head start centers

BACKGROUND

The impact of preschool environmental conditions on classroom aeroallergen concentrations is not fully understood.

OBJECTIVE

To examine the relationship between school environmental conditions and classroom aeroallergen concentrations in the Pulaski County Head Start (HS) Program.

METHODS

Thirty-three HS centers in Pulaski County, Arkansas, underwent a detailed environmental evaluation. Classroom settled dust samples were analyzed for the presence of common indoor allergens.

RESULTS

Classroom eating (70%), wall-to-wall carpeting (58%), and water damage (33%) were common. Median classroom allergen levels were as follows: dust mite (Der p 1 and Der f 1), 0.6 microg/g; Fel d 1, 0.4 microg/g; Can f 1, 1.7 microg/g; cockroach, below detection; Mus m 1, 0.18 microg/g; and mold spores, 17,800 CFU/g. Can f 1 and Mus m 1 allergens were detected in 100% of HS centers. Facilities with carpeting, increased humidity, and single-use facilities showed trends toward increased dust mite concentrations. Detectable cockroach allergen was more common in classrooms cleaned by teachers than by professional housekeepers.

CONCLUSIONS

Aeroallergens were commonly detected in Pulaski County HS center classrooms, with dog and mouse allergens detected in 100% of centers. Median classroom allergen concentrations were low, and classroom characteristics were not strongly predictive of increased allergen exposure.

Allergen inactivation with colloidal silica

We evaluated the allergen inactivating effect of colloidal silica by performing enzyme-liked immunosorbent assay (ELISA) whose wells were coated with 150 ng/mL of Japanese cedar pollen allergen (Cry j 1) or mite allergen (Der f 2). The allergens were almost 100% inactivated by 100 microg/mL of colloidal silica having a particle size 5 nm, and the inactivating effect was increased by aluminum binding to the surface of the colloidal silica. The results show that colloidal silica is a promising material for allergen inactivation. Since colloidal silica forms an insoluble nondispersive solid when dried, it is expected that airborne allergens can be reduced by binding them to colloidal silica.

Domestic allergens and endotoxin in three hospitals offering in-patient rehabilitation for allergic diseases in the alpine mountain climate of Bavaria - The AURA study

Endotoxins and allergens represent the major relevant contents of the atmospheric bioaerosol with regard to the triggering and exacerbation of allergic diseases. In this study, mattress concentrations of endotoxin and indoor allergens were measured in three hospitals in the alpine climate of Bavaria and in adjacent homes. Dust was collected from each of 10 mattresses according to a standardized protocol, and endotoxin was analyzed with the Limulus Amebocyte Lysate (LAL) test, indoor allergens Der p 1, Der f 1 and Fel d 1 were analyzed by ELISAs. The concentration of endotoxin in the mattresses did not differ significantly between different cities. The percentiles of endotoxin were significantly higher in hospitals than in homes. The concentrations of mite allergens (Der p 1 and Der f 1) in the dust were significantly lower in all hospitals than in homes. There was no significant difference of mite allergens between different time points. The concentrations of Fel d 1 were significantly higher in the autumn than in the summer (median: 1376 vs. 478ng/g). No significant differences of Fel d 1 were found between hospitals and homes or between different hospitals. As Fel d 1 concentrations reached levels at which cat allergic patients can experience symptoms, efforts had to be made to reduce the concentrations of Fel d 1 especially in hospitals. In contrast, mite allergens were low in hospitals, which can be clinically beneficial for patients with mite allergies.

Room-specific characteristics of suburban homes as predictors of indoor allergen concentrations

BACKGROUND

Room characteristics predicting indoor allergen exposure in suburban homes have not been clearly identified.

OBJECTIVE

To examine relationships between room characteristics and concentrations of indoor allergens in homes of suburban asthmatic patients.

METHODS

The homes of 339 asthmatic children ages 6 to 17 years were studied. Home inspections were conducted by a trained technician, and dust samples were analyzed for indoor allergen content. A high allergen concentration was defined as 8 microg (U)/g or more of fine dust.

RESULTS

Infrequent sheet washing and wall-to-wall carpet were risk factors for high bedroom dust mite concentrations. Infrequent sheet washing was also a risk factor for high Fel d 1 concentrations. Food remains in the bedroom was a risk factor for high bedroom Bla g 1 levels, and exposed food, leaks, and dirty pots were all risk factors for high kitchen Bla g 1 levels. The combination of lack of mattress or pillow encasements, infrequent sheet washing, and carpeting was associated with a 24-fold increase in odds of a high dust mite concentration (odds ratio [OR], 24.1; 95% confidence interval [CI], 3.2-181.4). Among non-cat owners, the combination of stuffed toys on the bed, lack of mattress or pillow encasements, and infrequent sheet washing was associated with a 49-fold increase in odds of a high Fel d 1 level (OR, 49.4; 95% CI, 2.8-887.3). The combination of leaks, exposed food, and dirty pots was associated with a high kitchen Bla g 1 concentration (OR, 10.6; 95% CI, 2.8-40.5).

CONCLUSIONS

Specific room characteristics predict high indoor allergen exposure among children with asthma, and a combination of these characteristics may further increase the risk of high allergen exposure.

Exhaled nitric oxide levels in school children in relation to IgE sensitisation and window pane condensation

BACKGROUND

A positive relation between exhaled nitric oxide (NO) levels and allergen exposure has been found in some studies whereas there is less information on how non-allergen environmental factors influences exhaled NO.

OBJECTIVE

To study the relationship between exhaled NO levels in schoolchildren in relation to IgE sensitisation and allergenic and non-allergenic environmental factors.

METHOD

This study comprised 374 schoolchildren (13-14 years of age) who performed exhaled NO-measurements and skin prick tests. Exposure to allergens, respiratory infections, environmental tobacco smoke and home window pane condensation, the latter an indicator of high humidity and poor ventilation was evaluated through questionnaires.

RESULTS

In IgE-sensitised children sensitisation to pets was a more important determinant of exhaled NO than sensitisation to pollen. Higher NO levels were found in cat-sensitised children with a cat or other furred pets at home compared to cat-sensitised children without pets (geometric mean, 24.0 vs. 13.9 ppb, P=0.03). Significantly higher exhaled NO levels were found in non-sensitised children that reported having a cold (5.7 vs. 3.8 ppb, P<0.001) or lived in homes with window pane condensation (7.1 vs. 4.4 ppb, P=0.01) than in non-sensitised children without a cold and window pane condensation, respectively. These associations were not found in children that were sensitised to inhalation allergens.

CONCLUSION

Allergen exposure seems to be the most important determinant for exhaled NO levels in IgE-sensitised children whereas in non-sensitised children NO levels were associated with respiratory infections and home window pane condensation.

High allergen exposure as a risk factor for asthma and allergic disease

The association between pet ownership in childhood and subsequent asthma and sensitization is very controversial. Intriguing, but contradictory, reports have caused considerable uncertainty in parents who wish to avoid asthma and allergic disease in their children. This article argues that high allergen exposure is a risk factor for asthma and allergic disease. It describes dispersal of pet allergens in society and critically assesses epidemiological studies regarding how early exposure to pet allergens affects subsequent immunoglobulin E-sensitization and allergic diseases. Additionally, this article evaluates the effects of allergen exposure in already sensitized subjects with asthma. Cat and dog allergens are ubiquitous in society and may induce sensitization and allergic symptoms in predisposed individuals, regardless of pet ownership. This, in combination with selection mechanisms for pet ownership in families with a history of allergic diseases, makes it difficult to study associations between early exposure to pets and subsequent allergic disease. Nevertheless, exposure to pet allergens worsens asthma in already sensitized children. Thus, it is clear that clinicians should advise sensitized asthmatics that avoidance of exposure to indoor allergens is an important element in the treatment of allergic disease.