- Email: [email protected]
HEPA air filtration units in homes with cats: Can they reduce personal exposure to cat allergen?
S56 A b s t r a c t s
J ALLERGY CLIN IMMUNOL JANUARY 2002
21
HEPAAir Filtration Units in Homes With Cats: Can They Reduce Personal Exposureto Cat Allergen? S Bishop*, B Durrell*, RB Gore§, EC McKie§, Adnan Custovic§, Ashley A Woodcock§ *North West Lung Center, Manchester, UK §Wythenshawe Hospital, Manchester, UK Studies on domestic pet allergen reduction have used proxy measures to assess personal allergen exposure and suggest that up to 80-95% reduction in airborne pet allergen can be achieved by domestic air filtration. We have used the intra Nasal Air Sampler to assess the effectiveness of high efficiency particle air (HEPA) filtration units in homes with cats on directly inspired cat allergen (Fel d 1) exposure. Two volunteers wore nasal samplers in 5 homes. Homes were visited on 4 different days (filtration on/off, cat in/out of the room). Nasal air samples were taken at baseline, then at 1, 2 and 3 hours. Nasal air samples were immunostained using an anti-Fel d 1 monoclonal antibody according to the Halogen protocol (Inhalix Pty, Sydney, Australia). Fel d 1-bearing particles were counted by light microscopy. Count data were square root transformed for analysis of variance (repeated measures). The data tabulated are square root detransformed mean counts with 95% confidence intervals and represent the number of particles inspired carrying cat allergen. The air filtration unit significantly reduced Fel d 1 exposure (F=28.060, df 1,4, p--0.006) whether or not the cat was in the room. Most of the reduction appeared to occur by the first time point after baseline (F=22.943, df 3,12, p<0.001). However, with the cat in the room, the reduction achieved compared with control (mean counts 29-12 vs 25-19) is way below that expected from other studies. The presence of a cat in the room (F=57.794, df 1,4, p--0.002) significantly raised personal Fel d 1 exposure 2.4 fold. Personal exposure to Fel d 1 in homes with cats can be reduced by the use of domestic air filtration units. However, in this real-life study, exposure to Fel d 1 was not reduced to the extent seen in studies using proxy measures of allergen exposure. This could be due to filtration of allergen by traditional air samplers themselves and may explain the lack of clinical efficacy seen in trials of air cleaners.
Cat in the room Active Baseline 1 hr 2hrs 3 hrs
l
29 (21,39) 12 (8,17) 10(5,16) 14 (10,19)
Control 25 (18,33) 19 (13,26) 24(19,28) 23 (18,28)
Cat elsewhere Active
Control
12 (8,18) 8 (5,13) 7(4,11) 5 (3,8)
18 (16,19) 15 (9, 23) 9 (3,18) 11 (5,18)
~e~e) Indoor Airborne Fungal Spores and Home Characteristics in /--I--- Asthmatic Children From Edirne Region of Turkey
Mehtap Yazicioglu*, Ahmet Asan§, Ulker OnesY, Ulfet Vatansever*, Burhan Sen~, Mevlut Ture§, Musa Bostancioglu*, Ozer Pala* *Trakya University Department of Pediatrics, Edime, Turkey §Trakya University Department of Biostatistics, Edirne, Turkey Ylstanbul University, Istanbul Medical Faculty, Istanbul, Turkey CTrakya University Department of Biology, Edirne, Turkey BACKGROUND: Fungi are the most numerous and diverse living particles in the air we breathe. However, the contribution of indoor fungal exposure to respiratory allergic diseases is still not completely clear. OBJECTIVE: This study was performed to investigate airborne fungal flora within the homes of asthmatic and control children and to assess the influence of housing characteristics regarding indoor fungi. METHODS: Forty-seven asthmatic and 23 nonatopic control children were included into the study. Allergen sensitivity was determined by skin prick tests with extracts of common aeroallergens. A thorough assessment, using a questionnaire and inspection surveys, was carried out. Indoor temperature and humidity were measured. Sampling visits were made to each house between October 2000 and February 2001. Samples for airborne fungal spores were collected from bedrooms, living rooms, kitchens and bathrooms by exposing a petri dish with Rose-Bengal streptomycin agar. After sampling, the petri plates were directly incubated at 25°C - 27°C for 6 - 7 days and then the number of colony forming units was counted.
RESULTS: The total indoor fungal colony counts from the living rooms and bedrooms were significantly higher in the asthma group than controls (p=.012 and p=.003, respectively). The most common isolated genus was Cladosporium, followed by Rhizopus, Penicillium, Alternaria, and Aspergillus. Twelve of the asthmatic patients (25.53 %) were found to be sensitive to fungal allergens. Logistic regression was used to investigate the associations between indoor fungal growth and potential risk factors such as type of ventilation, water damage, wall-to-wall carpeting, number of occupants of dwelling, reported or observed signs of dampness (the total colony counts were grouped as being higher and less than 2). Visible fungal patches in the bathrooms [(Odd's ratio (O.R) = 5.75; 95 % CI 1.19 to 27.70)], and the age of the house [O.R = 4.24; 95 % CI 1.34 to 13.45] were found to be associated with indoor fungal growth. Total fungal colony numbers did not significantly correlate with indoor temperature or humidity. CONCLUSION: Fungal colony numbers were higher in the homes of asthmatic children than the controls. Therefore, indoor fungal exposure may contribute to childhood asthma. Bathrooms were the main source of fungal propagules. The old houses were more prone to fungal growth.
23
Risk Factors of Bronchial Asthma in Filipino Children
Shirley. Lam Kwong, Agnes Gonzalez Andaya University of Santo Tomas Hospital, Quezon City, Philippines BACKGROUND: Certain risk factors may influence the severity of bronchial asthma in children. OBJECTIVES: To determine the relationship of certain risk factors with the severity of asthma. METHODS: Ninety asthmatic children seen at the Santo Tomas University Hospital Children's Asthma Unit were included in the study. Gender, age of gestation, family size, birth order, family history of atopy, feeding history, exposure to maternal smoke and environmental tobacco smoke, exposure to pets and harbingers of dust mites were the risk factors studied. Chi square test and the simple logistic regression were used to determine if relationship between risk factors and severity of bronchial asthma exists. RESULTS: Ninety asthmatic children were seen, 60% with intermittent asthma and 40% with persistent asthma. The duration of breastfeeding (exclusive and partial) was significantly associated with the severity of bronchial asthma. The longer the duration of breastfeeding up to 40 weeks, the lesser the probability of getting persistent asthma, p value=0.0398. Family size had borderline significance with the severity of bronchial asthma, the larger the family size up to six children, the lesser the probability of having persistent asthma, p value=0.0943. Gender, age of gestation, family history of atopy, birth order, duration of exclusive breastfeeding, exposure to maternal and environmental tobacco smoke, exposure to pets and harbingers of dust mites and onset of weaning were not found to be significantly associated with the severity of bronchial asthma. CONCLUSION: The duration of breastfeeding (exclusive and partial) was significantly associated with the severity of bronchial asthma while family size had borderline significance with the severity of bronchial asthma. Gender, age of gestation, family history of atopy, birth order, duration of exclusive breastfeeding, exposure to maternal smoke, environmental tobacco smoke, exposure to pets and harbingers of dust mites and onset of weaning were not found to be significantly associated with the severity of bronchial asthma.
124
Risk Factors for Asthma and Wheezing in Schoolchildren
Gustavo F Wandalsen, ln~s C Camelo Nunes, Karyn C Mello, Charles Naspitz, Dirceu Sol~ University Federal de S~o Paulo, Sao Paulo, Brazil In order to study risk factors associated with asthma and wheezing in schoolchildren, a written questionnaire (WQ) was submitted to parents and/or guardians of 6-7 year-old schoolchildren, living in the south area of S~o Paulo (SP, Brazil). The WQ was composed by the ISAAC's questionnaire and some extra questions regarding familial history of asthma and eczema, exposure to house dust mites, molds, environmental tobacco smoke (ETS), cats and dogs. The response rate was 70% and 1972 WQ
J ALLERGY CLIN IMMUNOL JANUARY 2002
21
HEPAAir Filtration Units in Homes With Cats: Can They Reduce Personal Exposureto Cat Allergen? S Bishop*, B Durrell*, RB Gore§, EC McKie§, Adnan Custovic§, Ashley A Woodcock§ *North West Lung Center, Manchester, UK §Wythenshawe Hospital, Manchester, UK Studies on domestic pet allergen reduction have used proxy measures to assess personal allergen exposure and suggest that up to 80-95% reduction in airborne pet allergen can be achieved by domestic air filtration. We have used the intra Nasal Air Sampler to assess the effectiveness of high efficiency particle air (HEPA) filtration units in homes with cats on directly inspired cat allergen (Fel d 1) exposure. Two volunteers wore nasal samplers in 5 homes. Homes were visited on 4 different days (filtration on/off, cat in/out of the room). Nasal air samples were taken at baseline, then at 1, 2 and 3 hours. Nasal air samples were immunostained using an anti-Fel d 1 monoclonal antibody according to the Halogen protocol (Inhalix Pty, Sydney, Australia). Fel d 1-bearing particles were counted by light microscopy. Count data were square root transformed for analysis of variance (repeated measures). The data tabulated are square root detransformed mean counts with 95% confidence intervals and represent the number of particles inspired carrying cat allergen. The air filtration unit significantly reduced Fel d 1 exposure (F=28.060, df 1,4, p--0.006) whether or not the cat was in the room. Most of the reduction appeared to occur by the first time point after baseline (F=22.943, df 3,12, p<0.001). However, with the cat in the room, the reduction achieved compared with control (mean counts 29-12 vs 25-19) is way below that expected from other studies. The presence of a cat in the room (F=57.794, df 1,4, p--0.002) significantly raised personal Fel d 1 exposure 2.4 fold. Personal exposure to Fel d 1 in homes with cats can be reduced by the use of domestic air filtration units. However, in this real-life study, exposure to Fel d 1 was not reduced to the extent seen in studies using proxy measures of allergen exposure. This could be due to filtration of allergen by traditional air samplers themselves and may explain the lack of clinical efficacy seen in trials of air cleaners.
Cat in the room Active Baseline 1 hr 2hrs 3 hrs
l
29 (21,39) 12 (8,17) 10(5,16) 14 (10,19)
Control 25 (18,33) 19 (13,26) 24(19,28) 23 (18,28)
Cat elsewhere Active
Control
12 (8,18) 8 (5,13) 7(4,11) 5 (3,8)
18 (16,19) 15 (9, 23) 9 (3,18) 11 (5,18)
~e~e) Indoor Airborne Fungal Spores and Home Characteristics in /--I--- Asthmatic Children From Edirne Region of Turkey
Mehtap Yazicioglu*, Ahmet Asan§, Ulker OnesY, Ulfet Vatansever*, Burhan Sen~, Mevlut Ture§, Musa Bostancioglu*, Ozer Pala* *Trakya University Department of Pediatrics, Edime, Turkey §Trakya University Department of Biostatistics, Edirne, Turkey Ylstanbul University, Istanbul Medical Faculty, Istanbul, Turkey CTrakya University Department of Biology, Edirne, Turkey BACKGROUND: Fungi are the most numerous and diverse living particles in the air we breathe. However, the contribution of indoor fungal exposure to respiratory allergic diseases is still not completely clear. OBJECTIVE: This study was performed to investigate airborne fungal flora within the homes of asthmatic and control children and to assess the influence of housing characteristics regarding indoor fungi. METHODS: Forty-seven asthmatic and 23 nonatopic control children were included into the study. Allergen sensitivity was determined by skin prick tests with extracts of common aeroallergens. A thorough assessment, using a questionnaire and inspection surveys, was carried out. Indoor temperature and humidity were measured. Sampling visits were made to each house between October 2000 and February 2001. Samples for airborne fungal spores were collected from bedrooms, living rooms, kitchens and bathrooms by exposing a petri dish with Rose-Bengal streptomycin agar. After sampling, the petri plates were directly incubated at 25°C - 27°C for 6 - 7 days and then the number of colony forming units was counted.
RESULTS: The total indoor fungal colony counts from the living rooms and bedrooms were significantly higher in the asthma group than controls (p=.012 and p=.003, respectively). The most common isolated genus was Cladosporium, followed by Rhizopus, Penicillium, Alternaria, and Aspergillus. Twelve of the asthmatic patients (25.53 %) were found to be sensitive to fungal allergens. Logistic regression was used to investigate the associations between indoor fungal growth and potential risk factors such as type of ventilation, water damage, wall-to-wall carpeting, number of occupants of dwelling, reported or observed signs of dampness (the total colony counts were grouped as being higher and less than 2). Visible fungal patches in the bathrooms [(Odd's ratio (O.R) = 5.75; 95 % CI 1.19 to 27.70)], and the age of the house [O.R = 4.24; 95 % CI 1.34 to 13.45] were found to be associated with indoor fungal growth. Total fungal colony numbers did not significantly correlate with indoor temperature or humidity. CONCLUSION: Fungal colony numbers were higher in the homes of asthmatic children than the controls. Therefore, indoor fungal exposure may contribute to childhood asthma. Bathrooms were the main source of fungal propagules. The old houses were more prone to fungal growth.
23
Risk Factors of Bronchial Asthma in Filipino Children
Shirley. Lam Kwong, Agnes Gonzalez Andaya University of Santo Tomas Hospital, Quezon City, Philippines BACKGROUND: Certain risk factors may influence the severity of bronchial asthma in children. OBJECTIVES: To determine the relationship of certain risk factors with the severity of asthma. METHODS: Ninety asthmatic children seen at the Santo Tomas University Hospital Children's Asthma Unit were included in the study. Gender, age of gestation, family size, birth order, family history of atopy, feeding history, exposure to maternal smoke and environmental tobacco smoke, exposure to pets and harbingers of dust mites were the risk factors studied. Chi square test and the simple logistic regression were used to determine if relationship between risk factors and severity of bronchial asthma exists. RESULTS: Ninety asthmatic children were seen, 60% with intermittent asthma and 40% with persistent asthma. The duration of breastfeeding (exclusive and partial) was significantly associated with the severity of bronchial asthma. The longer the duration of breastfeeding up to 40 weeks, the lesser the probability of getting persistent asthma, p value=0.0398. Family size had borderline significance with the severity of bronchial asthma, the larger the family size up to six children, the lesser the probability of having persistent asthma, p value=0.0943. Gender, age of gestation, family history of atopy, birth order, duration of exclusive breastfeeding, exposure to maternal and environmental tobacco smoke, exposure to pets and harbingers of dust mites and onset of weaning were not found to be significantly associated with the severity of bronchial asthma. CONCLUSION: The duration of breastfeeding (exclusive and partial) was significantly associated with the severity of bronchial asthma while family size had borderline significance with the severity of bronchial asthma. Gender, age of gestation, family history of atopy, birth order, duration of exclusive breastfeeding, exposure to maternal smoke, environmental tobacco smoke, exposure to pets and harbingers of dust mites and onset of weaning were not found to be significantly associated with the severity of bronchial asthma.
124
Risk Factors for Asthma and Wheezing in Schoolchildren
Gustavo F Wandalsen, ln~s C Camelo Nunes, Karyn C Mello, Charles Naspitz, Dirceu Sol~ University Federal de S~o Paulo, Sao Paulo, Brazil In order to study risk factors associated with asthma and wheezing in schoolchildren, a written questionnaire (WQ) was submitted to parents and/or guardians of 6-7 year-old schoolchildren, living in the south area of S~o Paulo (SP, Brazil). The WQ was composed by the ISAAC's questionnaire and some extra questions regarding familial history of asthma and eczema, exposure to house dust mites, molds, environmental tobacco smoke (ETS), cats and dogs. The response rate was 70% and 1972 WQ