Mite Allergen Levels Research Articles

Mite allergen levels and fungal counts in children's bedding in four widely separated towns in Japan

We evaluated the relationships between children's housing, earthquake or tsunami damage affecting children, prevalence of allergic diseases, and levels of mite allergens and fungi on children's bedding after the Great East Japan Earthquake in four municipalities in Japan. We surveyed 464 children in Ishinomaki, 254 in Kami, 614 in Iwanuma, and 300 in Oiso whose parents or guardians had completed the International Study of Asthma and Allergies in Childhood questionnaire. We measured the levels of Dermatophagoides 1 allergens (Der 1) (Dermatophagoidespteronyssinus and Dermatophagoides farinae) on children's mattresses or futons and fungal counts (Aspergillus and yeast) between 2016 and 2018. Earthquake damage was significantly greater in Ishinomaki than in the other three municipalities. There were no differences in the prevalence of allergic disease among the four municipalities. Der 1 levels were significantly higher in Ishinomaki than in Iwanuma, but there were no differences among Oiso, Iwanuma, and Kami. Der 1 levels in children with asthma in Iwanuma and with allergic rhinitis in Kami were significantly higher than in those without these conditions. Total fungal counts and Aspergillus counts were highest in Kami and lowest in Oiso. Der 1 levels were significantly correlated with fungal counts in Kami and Iwanuma, but not in Ishinomaki or Oiso. Both Der 1 levels and total fungal counts in Ishinomaki were greater than those in other three municipalities. Housing and allergen-avoidance strategies varied among the four municipalities. Mite allergen and fungal levels in these Japanese municipalities might have been affected by the earthquake and tsunami, and these changes might have affected the prevalence of allergic diseases in children.

The prevalence of IgE positivity, environmental factors, and clinical implications associated with mite species in allergic patients in Taiwan.

Allergic diseases are a growing public health concern with increasing prevalence and severity. Allergens play significant roles in triggering immune responses and the development of allergic reactions. Investigate the presence and clinical significance of dust mites, storage mites, and predatory mite Cheyletus eruditus(Ce) in household environments. A survey of household dust was performed to determine mite occurrence and analyze influencing factors, an analysis of the correlation between mite species and allergic symptoms, and basophil activation triggered by mite allergens. Cross-reactivity between Ce and house dust mites was assessed. The high appearance rate of mite species in households of Taiwan was Dermatophagoides pteronyssinus (Dp) and D. farinae(Df). Environmental factors such as pet keeping, vacuum cleaner usage, air conditioner usage, proximity to the kitchen, cleaning frequency, and protein concentration in beds were shown to influence mite prevalence. The appearance of Dp and Df significantly increased the occurrence of airway and nasal symptoms, while the presence of Ce was strongly correlated with skin symptoms. The activation of basophils and the correlation between specific IgE levels and allergic symptoms in response to Ce exposure were demonstrated. The presence of Ce was associated with elevated levels of allergens in bedding. The IgE adsorption between mite species was demonstrated suggesting cross-reactivity between the Ce and Dp was limited. Presence of Ce is associated with elevated levels of major mite allergens in beddings. Allergenicity of Ce was confirmed by IgE reactivity and basophil activation regarding mite infestation as a potential cause of skin-related allergy.

Residual profiles and health risk of indoor allergens in China

Exposure to indoor allergens is a principal risk factor for allergic diseases. However, most of the previous studies on indoor allergens focused on very limited kinds of allergens in China. Knowledge of the simultaneous exposure to multiple allergens is still lacking. In this study, the residual profiles of 8 allergens were investigated in 166 dust samples from 11 cities in China. The house dust mite allergens including Der p 1, Der f 1, and Der 2 were detected in the range of <0.02–283.83 μg/g dust. The concentrations of dog allergen Can f 1 and cat allergen Fel d 1 varied widely, from <0.84–22,896.46 μg/g dust for Can f 1 and from <0.02–6298.96 μg/g dust for Fel d 1. Cockroach allergen Bla g 2 was detected in 68% of the samples but at a low level with a maximum of 9.44 μg/g dust. Comparatively low detection frequencies were found for mouse allergen Mus m 1 as 37% and for fungi allergen Asp f 2 as 24%. The frequency of cleaning sheets/bedding was negatively correlated to the levels of house dust mite allergens. The presence of pets indoors was associated with higher levels of pet allergens and lower levels of house dust mite allergens and cockroach allergen. Risk evaluation reveals that at least 4 allergens were found in more than 80% of the rooms and more than 2 allergens with median/high risk were detected in 42% of the rooms, indicating that simultaneous exposure to multiple allergens is prevalent in China.

Exposure levels of animal allergens, endotoxin, and β-(1,3)-glucan on a university campus of veterinary medicine.

The study aimed to determine the allergen, endotoxin and β-(1,3)-glucan concentrations at various areas on a university campus of veterinary medicine. Dust samples were collected four times a year for three years using electrostatic dust collectors (EDC) at 25 different locations on a campus of veterinary medicine and in laboratories of inorganic chemistry as a control area representing animal-free environment. Major animal allergens from dog, cat, horse, cattle and mouse, domestic mite (DM) allergens, and β-(1,3)-glucan were measured using enzyme immunoassays and endotoxin using the limulus amoebocyte lysate (LAL) assay. Seasonal, annual and local influences on exposure levels were analyzed using Bayesian mixed models. With the exception of mouse allergens, all other determinants were found in almost all locations on the campus and in the control area, but in up to 10.000-fold variable concentrations. By far the highest levels of feline, canine, equine and bovine allergens were detected in buildings where the respective species were examined. The highest levels of mouse and DM allergens, β-(1,3)-glucan and endotoxin occurred together and were associated with locations where large animals were present. In buildings without animals, allergen levels were considerably lower but still elevated at several locations compared to the control area, especially for dog and horse allergens, and β-(1,3)-glucan. Significant seasonal effects were observed for dog, cat, horse and DM allergens, and β-(1,3)-glucan. Variations between years were less apparent than between seasons (except for β-(1,3)-glucan). The strongest influencing factor on the concentration of mammalian allergens was the presence of the corresponding animal at the collection site. Seasonal influence on allergen concentrations was observed, while the overall exposure remained constant over the years. At locations with horses, elevated levels of mite allergens, endotoxin, and β-(1,3)-glucan can be expected, probably due to passive transfer from stable environment.

Effects of mite allergen avoidance in children in two distant towns in Japan

We investigated the prevalence of asthma, rhinitis, and atopic dermatitis and evaluated changes in mite allergen levels on mattresses and allergic symptoms in children after allergen avoidance in two distant regions of Japan after the Great East Japan Earthquake. We performed an International Study of Asthma and Allergies in Childhood survey of 49 school children aged 6–10years in Iwanuma in 2017 and 57 school children aged 6–10years in Oiso in 2018, and measured levels of Dermatophagoides group 1 (Der 1) in their bedding. Children in the intervention group attended an allergen avoidance seminar. In the same season the following year, we again measured Der 1 level in bedding and examined changes in allergic symptoms. Children in the non-intervention group did not attend this seminar. The prevalence of asthma, rhinitis, and atopic dermatitis and the types and ages of houses at study entry did not differ between the two towns. At first measurement, the Der 1 level in the intervention group was higher at Iwanuma than at Oiso (P<0.05). The Der 1 level in the intervention group in both towns significantly decreased after implementing allergen avoidance (P<0.01) but did not decrease in either non-intervention group. In each town, symptoms of allergic rhinitis was significantly lower (P<0.05) among children whose Der 1 level were reduced to less than 10% of initial levels. Mite allergen levels in two distant regions in Japan differed slightly. Allergen avoidance ameliorated allergic symptoms in school children.

Mite allergen avoidance decreases allergic symptoms in children in Ishinomaki city of Japan after natural disasters.

We investigated the prevalence of asthma, rhinitis, and atopic dermatitis in children, evaluated the mite allergen levels in their bedding after the Great East Japan Earthquake, and assessed changes in allergic symptoms in children and their families after allergen avoidance practices. We performed a survey for the International Study of Asthma and Allergies in Childhood (ISAAC) comprising 1109 children, aged 7-8 years, living in Ishinomaki, Japan. We collected responses from 464 children, and in 2016, measured the level of Dermatophagoides group 1 (Der 1) in the bedding of 202 of these children. The intervention group of children attended at least one allergen avoidance seminar. The levels of Der 1 in their bedding were measured, along with changes in allergic symptoms, in 17 children in 2017 and 14 children in 2018. The nonintervention group comprised children who did not attend an allergen avoidance seminar at any time. Of the 464 children who participated in the ISAAC, 50 (10.8%) reported having asthma, 179 (38.8%) allergic rhinitis, and 126 (27.3%) atopic dermatitis. The average level of Der 1 measured in the bedding of the 202 children in 2016 was 295.8 ng/m2. The levels of Der 1 in the intervention group-but not in the nonintervention group-significantly decreased in 2017 and 2018. The symptoms of asthma, allergic rhinitis, and atopic dermatitis in the children of intervention group and their families decreased after allergen avoidance practices. Allergen avoidance practices relieved allergic symptoms in school children after the Great East Japan Earthquake.

Molecular allergy profile to house dust mites in Galicia (Spain)

House dust mites (HDM) are an important source of perennial allergens that play a key role in the development of rhinitis and allergic asthma.Specifically in Galicia there are very high levels of mite allergens, which poses an important clinical problem. We used mollecular diagnosis to investigate the sensitization profile to houses dust mites in our region

Seasonal changes of mite allergen (Der 1) levels in houses with different architectural styles and ventilation systems

Research on the influence of different architectural styles and ventilation systems on mite allergen levels is crucial to decrease mite allergen exposures in houses. The purpose of this study was to examine the seasonal changes in mite allergen (Der 1) levels on the floors and mattresses of houses with different architectural styles and ventilation systems.

Ultrasonic "Mite Killers” Fail to Decrease Mites in Carpeting

Reactivity to house dust mites is a major cause of allergic disease, the treatment of which includes allergen-avoidance. To be of possible clinical benefit, any claimed allergen-avoidance measure must actually result in a meaningful decrease of the allergen. Several devices advertised online claim to decrease dust mite survival and numbers by the use of ultrasonic sound. One published study claimed clinical benefit from such a device, but no published data demonstrate the ability of these devices to actually decrease mite numbers or allergen levels.

RISK FACTORS FOR INNER CITY ASTHMA PATIENTS

Asthma patients in inner cities have the highest prevalence of asthma and the highest death rates in America. The purpose of this study was to evaluate sensitization and exposure to common indoor allergens seen for asthma treatment at Grady Memorial Hospital, Atlanta, Ga. Eighty asthma patients were enrolled in the emergency department and 64 in hospital clinics in this study. Neither sensitization nor visibility In this population, cat allergens are prevalent. The findings show that black asthma patients are exposed to high levels of mite and cockroach allergens in downtown Atlanta and that a high percentage of patients with asthma are sensitized to these allergens; a significant risk factor for asthma in this population is the combination of sensitization and exposure.&#x0D; Keywords: asthma; mechanical ventilation, status asthmaticus , Pathophysiology epidemiology mechanisms.

House Dust Mite Allergen Levels of Der p1 and Der f1 in Houses of Asthmatic Children

Background: Exposure to house dust mites is an important cause of asthma among children. The main asthma-causing mites found in homes are Dermatophagoides farinae and Dermatophagoides. pteronyssinus. Der f1 or Der p1 are allergens of the mentioned mites. This study aimed to assess the levels of Der p1, and Der f1 in the homes of families that had a case of childhood asthma in a northern city of Iran and to determine the association between indoor house environment and the level of mites allergens present there. Objectives: This study aimed to evaluate House Dust Mite Allergen Levels of Der p1 and Der f1 in Houses of Asthmatic Children. Methods: Dust samples were collected from bedrooms of 91 homes of families that had cases of childhood asthma. Families filled a questionnaire about demographical characteristics and the indoor condition of their living environment. The levels of Der f1 and Der p1 were measured by enzyme-linked immunosorbent assay (ELISA). Statistical analysis was performed in SPSS v. 24 and a P-value less than 0.05 was considered significant. Results: we found that Der p1 was more prevalent than Der f1 among samples. The mean concentration of Der p1 concentration was 271.35 ng/g (9 times greater than the concentration of Der f1). When the indoor environment status was evaluated, it was found that keeping pets and having old carpets are associated with Der f1 (P&lt;0.05). However, no significant association was found between Der p1 and the indoor conditions of the home. Conclusions: Our study showed that Der p1 level is higher than Der f1 level in the houses of children with asthma. We suggest removing carpets and pets from the house.

Early-life inhalant allergen exposure, filaggrin genotype, and the development of sensitization from infancy to adolescence

BackgroundWe hypothesized that filaggrin (FLG) loss-of-function mutations modify the effect of allergen exposure on the development of allergic sensitization.ObjectiveWe sought to determine whether early-life exposure to inhalant allergens increases the risk of specific sensitization and whether FLG mutations modulate these odds.MethodsIn a population-based birth cohort we measured mite, cat, and dog allergen levels in dust samples collected from homes within the first year of life. Sensitization was assessed at 6 time points between infancy and age 16 years. Genotyping was performed for 6 FLG mutations.ResultsIn the longitudinal multivariable model (age 1-16 years), we observed a significant interaction between FLG and Fel d 1 exposure on cat sensitization, with the effect of exposure being significantly greater among children with FLG mutations compared with those without (odds ratio, 1.36; 95% CI, 1.02-1.80; P = .035). The increase in risk of mite sensitization with increasing Der p 1 exposure was consistently greater among children with FLG mutations, but the interaction did not reach statistical significance. Different associations were observed for dogs: there was a significant interaction between FLG and dog ownership, but the risk of sensitization to any allergen was significantly lower among children with FLG mutations who were exposed to a dog in infancy (odds ratio, 0.16; 95% CI, 0.03-0.86; P = .03).ConclusionsFLG loss-of-function mutations modify the relationship between allergen exposure and sensitization, but effects differ at different ages and between different allergens.

Effects of Air Pollution and Land Use Characteristics on Development and Respiratory Health among Children in the Greater Taipei Area

Indoor and outdoor air pollution poses an important health threat to children. Exposure to air pollution may cause various acute and chronic respiratory diseases, and affect neurodevelopment and cognitive functions in children. To evaluate the impact of air pollution on children's health, we conduct a study to examine the effect of prenatal and early childhood exposure to air pollution on development and respiratory health in the first 3 years of life among a birth cohort in the Greater Taipei area. We will recruit 500 cohort children, and evaluate their development and respiratory diseases using standardized questionnaires and Bayley Scales of Infant and Toddler Development. One hundred children will be selected to conduct indoor and outdoor environmental samplings of their residences. Four hundred and fifty-six cohort children have been recruited so far, and environmental measurements have been implemented in 40 homes. According to our analyses, most ambient pollutant concentrations near participants' homes were lower than Taiwan National Ambient Air Quality Standard, expect PM2.5, which exceeded the annual average level (15µg/m3). A few households had elevated indoor pollution levels due to a low ventilation rate or recent remodeling. Several children's bed dust samples contained dust mite allergen levels &amp;gt; 2 µg/g, which may increase the risk of child sensitization to dust mites. According to multiple regression analyses, a high level of nitrogen oxides during first trimester near residence as well as living near gas stations, social welfare facilities, or high ways had adverse effects on children's health; living near green parks was beneficial to children's neurodevelopment. Overall, residential environments, such as air quality and land use type nearby, may significantly influence children's health and neurodevelopment.

House Dust and Its Adverse Health Effects

In this review, we examine house dust and its effect on inhabitants' health. Residential house dust includes components from plants, pollens, microorganisms, insects, skin flakes, hairs and fibers. It also includes materials contaminated with chemicals from combustion, furniture, interior materials, electronics, cleaning agents, personal care products. Nowadays, most people spend their time indoors. Thus, dust is an important medium of exposure to pollutions. According to United States Environmental Protection Agency Exposure Factors Handbook, the estimated amount of dust ingestion is 30 mg/day for adults, and 60 mg/day for children over 1 year of age. Since 2003, we have been conducting epidemiological studies to find the association between the indoor environment and the inhabitants' health. The levels of mite allergens, endotoxins, and β-1,3-d-glucan in house dust were measured as biological factors. Semi volatile organic compounds (SVOC) such as phthalates and phosphate flame retardants (PFRs) in dust were also analyzed. As a result, we found that the ORs (95%CI) of nasal and optical symptoms of sick building syndrome (SBS) were 1.45 (1.01-2.10) and 1.47 (1.14-1.88), respectively, when there was a 10-fold increase in the levels of mite allergens. There was no association of mite allergens with allergies. Endotoxins and β-1,3-d-glucan did not show any association with SBS. Regarding SVOC, increased levels of phthalates and PFR increased the risk of allergies. The association between phthalates and increased risk of allergies was clearer among children than adults. There were no gold standards of dust sampling and pretreatment methods. Thus, caution is needed when comparing findings of various studies. Methods should accurately reflect exposure levels.

Plasma Cluster Ions Reduce the IgE-Binding Capacity of House Dust Mite Allergens under a Simulated Indoor Environmental Condition

Background: A high level of house dust mite (HDM) allergens in a living environment is a risk factor for both sensitization to these allergens and asthmatic attacks. We previously showed that plasma cluster ions (PCIs) impaired the IgE-binding capacity of atomized crude allergens prepared from Japanese cedar pollen and fungus under experimental conditions. Objective: We evaluated the capacity of PCIs to impair the IgE-binding capacity of airborne HDM allergens under a simulated indoor environmental condition. Methods: For the determination of the effects of PCIs on HDM allergens under an experimental condition, HDM extract was atomized as aqueous mist into a cylindrical experimental apparatus filled with PCIs. For the evaluation of the effects of PCIs under a simulated natural indoor environmental condition, dried HDM allergens were floated as airborne particles in an acryl cubic apparatus in the presence of PCIs. The IgE-binding capacities of the PCI- and sham-treated HDM allergens were analyzed by an ELISA. Results: The IgE-binding capacity of the HDM allergens was significantly impaired after PCI treatment compared to that after sham treatment under both experimental and simulated environmental conditions. The ELISA results demonstrated that the IgE-binding capacities of HDM allergens after PCI treatment showed 68 and 74% reductions compared to those after sham treatment under the experimental and simulated environmental conditions, respectively. Conclusions: PCIs have the capacity to impair the IgE-binding capacity of airborne HDM allergens in a simulated environmental condition.

NIAID, NIEHS, NHLBI, and MCAN Workshop Report: The indoor environment and childhood asthma—implications for home environmental intervention in asthma prevention and management

Environmental exposures have been recognized as critical in the initiation and exacerbation of asthma, one of the most common chronic childhood diseases. The National Institute of Allergy and Infectious Diseases; National Institute of Environmental Health Sciences; National Heart, Lung, and Blood Institute; and Merck Childhood Asthma Network sponsored a joint workshop to discuss the current state of science with respect to the indoor environment and its effects on the development and morbidity of childhood asthma. The workshop included US and international experts with backgrounds in allergy/allergens, immunology, asthma, environmental health, environmental exposures and pollutants, epidemiology, public health, and bioinformatics. Workshop participants provided new insights into the biologic properties of indoor exposures, indoor exposure assessment, and exposure reduction techniques. This informed a primary focus of the workshop: to critically review trials and research relevant to the prevention or control of asthma through environmental intervention. The participants identified important limitations and gaps in scientific methodologies and knowledge and proposed and prioritized areas for future research. The group reviewed socioeconomic and structural challenges to changing environmental exposure and offered recommendations for creative study design to overcome these challenges in trials to improve asthma management. The recommendations of this workshop can serve as guidance for future research in the study of the indoor environment and on environmental interventions as they pertain to the prevention and management of asthma and airway allergies.

Genome-wide interaction study of dust mite allergen on lung function in children with asthma

Childhood asthma is likely the result of gene-by-environment (G×E) interactions. Dust mite is a known risk factor for asthma morbidity. Yet, there have been no genome-wide G×E studies of dust mite allergen on asthma-related phenotypes. We sought to identify genetic variants whose effects on lung function in children with asthma are modified by the level of dust mite allergen exposure. A genome-wide interaction analysis of dust mite allergen level and lung function was performed in a cohort of Puerto Rican children with asthma (Puerto Rico Genetics of Asthma and Lifestyle [PRGOAL]). Replication was attempted in 2 independent cohorts, the Childhood Asthma Management Program (CAMP) and the Genetics of Asthma in Costa Rica Study. Single nucleotide polymorphism (SNP) rs117902240 showed a significant interaction effect on FEV1 with dust mite allergen level in PRGOAL (interaction P=3.1×10-8), and replicated in the same direction in CAMP white children and CAMP Hispanic children (combined interaction P=.0065 for replication cohorts and 7.4×10-9 for all cohorts). Rs117902240 was positively associated with FEV1 in children exposed to low dust mite allergen levels, but negatively associated with FEV1 in children exposed to high levels. This SNP is on chromosome 8q24, adjacent to a binding site for CCAAT/enhancer-binding protein beta, a transcription factor that forms part of the IL-17 signaling pathway. None of the SNPs identified for FEV1/forced vital capacity replicated in the independent cohorts. Dust mite allergen exposure modifies the estimated effect of rs117902240 on FEV1 in children with asthma. Analysis of existing data suggests that this SNP may have transcription factor regulatory functions.

Evaporative Cooler Use Influences Temporal Indoor Relative Humidity but Not Dust Mite Allergen Levels in Homes in a Semi-Arid Climate

Concerns about energy consumption and climate change make residential evaporative coolers a popular alternative to central air conditioning in arid and semi-arid climates. However, evaporative coolers have been shown to significantly increase indoor relative humidity and dust mite allergen levels in some studies, while showing no association in other studies. Improved measurement of temporal fluctuations in indoor relative humidity may help identify factors that promote mite growth in homes in dry climates. Dust samples and continuous indoor relative humidity measurements were collected from homes with central air conditioning and homes with evaporative coolers in Utah. Samples were collected over two seasons, winter/spring (Jan–Apr) and summer (July–Sept), 2014. Dust samples were analyzed for Der p 1 and Der f 1 using a two-site monoclonal antibody-based enzyme-linked immunosorbent assay (ELISA) analysis. Housing characteristics including age of home, occupant density, and age of mattresses, furniture, and carpeting were also measured. Positive Der p 1 or Der f 1 samples were found in 25.0% of the homes and there was no difference in mean allergen levels by type of air conditioning. Indoor relative humidity was significantly higher in homes with evaporative coolers compared to those with central air conditioning during the summer. Homes with evaporative coolers also spent significantly more time during summer above 55.0% and 65.0% relative humidity compared to central air homes, but not above 75.0%. Findings from this study suggest that increased humidity from evaporative coolers may not be sufficient to exceed the critical equilibrium humidity or maintain humidity excursions for sufficient duration in relatively larger single-family homes in semi-arid climates to support mite growth and reproduction.

Indoor Allergen Levels and Household Distributions in Nine Cities Across China

ObjectiveChinese allergic subjects have high levels of sensitization to house dust mite (HDM) and other indoor allergens. This study quantifies common indoor allergen levels in Chinese households. MethodsDust samples were collected from nine cities. Major allergens Der p 1 and Der f 1 from Dermatophagoides pteronyssinus and D. farinae, and specific antigens of Blomia tropicalis, Tyrophagus putrescentiae, Acarus siro, and cockroach species Blattella germanica and Periplaneta americana were measured by ELISA. ResultsHDM allergens were found in dust samples from bedding in 95% of the Chinese households. The median levels varied from <0.006 to 9.2 µg/g of dust, depending on the city. The percentages of households having HDM allergen levels associated with the risk of developing allergy sensitization and asthma were 65% and 25%, respectively. Specific antigens of the storage mite and cockroach were only found in samples from the southern and tropical regions of China. Levels of mite allergens were generally higher in samples from bedding compared to samples from the living room, even for storage mites, whereas levels of cockroach antigens were higher in the living room samples. ConclusionHDM allergens are present in bedding dust samples from most Chinese households. Cities in southern and central China have relatively high levels of HDM major allergens compared to cities in northern and western China. Antigens of storage mites and cockroaches are not as common as HDM allergens.

Efficacy of an in-home test kit in reducing dust mite allergen levels: results of a randomized controlled pilot study

Background: Dust mite allergens can induce allergic sensitization and exacerbate asthma symptoms. Although dust mite reduction and control strategies exist, few asthmatics employ them. Objectives: We examined whether an in-home test kit, which quantifies dust mite allergen levels, resulted in behavioral changes in implementation and maintenance of mite reduction strategies and helped reduce allergen levels in homes of dust mite-sensitive children. Methods: We enrolled 60 households of children aged 5–15 with parent-reported dust mite allergy into a randomized controlled trial. Intervention homes (N = 30) received educational material about reducing dust mites and test kits at 1, 2, 5 and 8 months. Control homes (N = 30) received only educational material. At baseline, 6 and 12 months, study staff visited all homes, collected dust samples from three locations and obtained information about parents’ mite reduction behaviors by questionnaire. Allergen concentrations (Der f 2/Der p2) in dust were assessed by immunoassays. After adjusting for visit and location, allergen concentrations in intervention and control homes were compared using mixed effects model analysis. Results: In the intervention homes, allergen concentrations in the child’s bedroom and living room floors were significantly reduced over time compared to control homes. Although not all location-specific differences in allergen concentrations were statistically significant, combining data across locations, there was a differential reduction in allergen concentrations in the intervention group versus the control group (p = 0.02). Conclusion: The use of in-home test kits along with education may beneficially influence behaviors and attitudes toward dust mite reduction strategies and help reduce residential dust mite allergen levels.