***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: A r and omized comparison group pretest-posttest experimental design was used to quantitatively determine the effects of environmental control measures on patients with allergic rhinitis .  Environmental controls included wrapping the mattress with a vinyl cover , washing the top bedding cover with 55 degrees C hot water every two weeks , removal of soft furniture , and wet cleaning of the bedroom floor every day .  Thirty subjects were r and omly assigned to experimental and control groups . The amount of house dust mites in dust sample s collected from the bedroom floor , bedding and mattress , as well as the nasal symptoms of patients , were measured twice at one-month intervals . A significant decrease in house dust mites in dust sample s and relief in patients ' nasal symptoms were observed in the experimental group who had environmental controls Background : Environmental control has been put forward as an integral part of the management of house dust mite ( HDM ) allergy in sensitized patients . To vali date this statement allergic disorders involved in HDM allergy – allergic asthma , rhinitis and atopic eczema/dermatitis syndrome ( AEDS ) – should be taken together and studied in terms of the efficacy of environmental control . Because a generic quality of life question naire exceeds the border of disease , this may be used as major outcome parameter BACKGROUND Encasing bedding in impermeable covers reduces exposure to house-dust mites , but the clinical benefit of this intervention as part of mite-avoidance measures for patients with allergic rhinitis is not known . We performed a multicenter , r and omized , placebo-controlled trial of one year of use of impermeable bedding covers in the bedrooms of patients with rhinitis who were sensitized to house-dust mites to determine the effects on the signs and symptoms of disease . METHODS Three participating university medical centers enrolled 279 patients with allergic rhinitis who were r and omly assigned to receive impermeable or non-impermeable ( control ) covers for their mattress , pillow , and duvet or blanket .  At the start of the study , all participants received information on general allergen-avoidance measures . The severity of rhinitis was measured on a rhinitis-specific visual-analogue scale and by means of a daily symptom score and nasal allergen provocation testing . We also measured the concentrations of Dermatophagoides pteronyssinus ( Der p1 ) and D. farinae ( Der f1 ) in dust from patients ' mattresses , bedroom floors , and living-room floors at base line and after 12 months as a measure of the efficacy of the intervention . RESULTS A total of 232 patients completed the study . There was a significant reduction in Der p1 and Der f1 concentrations in the mattresses of the impermeable-cover group , whereas there was no significant reduction in the control group . However , there was no significant effect on the clinical outcome measures . Analyses of subgroups defined according to age , level of exposure , type and severity of sensitization , or characteristics of the patient 's home had similar results . CONCLUSIONS Mite-proof bedding covers , as part of a structured allergy-control program , reduced the level of exposure to mite allergens . Despite the success of the intervention , this single avoidance measure did not lead to a significant improvement of clinical symptoms in patients with allergic rhinitis A double blind , r and omized , comparative study versus placebo , was done during 6 months in 32 children , aged 4 - 12 years , who suffer from either allergic asthma or rhinitis or both , slept in a bedroom rich in dust mite , have well documented allergy solely to house dust mite ( H.D.M. ) , and a condition severe enough to require continuous medication . After thorough cleaning , their bedrooms were sprayed on day 0 and day 90 with the total content of a canister containing either Acardust or Placebo . Rooms were cleaned regularly throughout the study period . Each child completed an individual daily score card ( scales from 0 - 3 ) for asthma , and rhinitis symptoms , medication taken , and any additional symptoms . Peak flow was recorded twice weekly . All the children were examined every month ( at the clinic ) when also PFF , FEVI , doctor 's and patient 's opinion of clinical symptoms were recorded according to the same scale ( 0 - 3 ) and dust sample s from child 's bedroom were examined for H.D.M. antigen content . At day 0 , 90 and 180 , total IgE and dust mite specific IgE determination was done . At the end of the study , patient 's and doctor 's opinion about the spray 's efficacy were recorded on a scale from 0 - 3 . The results were in favor of Acardust for asthma , according to patient 's opinion ( p = 0.001 ) , doctor 's opinion ( p = 0.04 ) and individual score cards ( p = 0.03 ) , and for nasal secretion ( p = 0.01 ) , sneezing and lacrimation ( p = 0.02 ) ; concurrent medication dropped significantly ( p = 0.01 ) in the Acardust group . No side-effects were reported . We consider Acardust a safe and valuable preventive treatment in H.D.M. allergy BACKGROUND Data for trends in prevalence of asthma , allergic rhinoconjunctivitis , and eczema over time are scarce . We repeated the International Study of Asthma and Allergies in Childhood ( ISAAC ) at least 5 years after Phase One , to examine changes in the prevalence of symptoms of these disorders . METHODS For the ISAAC Phase Three study , between 2002 and 2003 , we did a  cross-sectional question naire survey of 193,404 children aged 6 - 7 years from 66 centres in 37 countries , and 304,679 children aged 13 - 14 years from 106 centres in 56 countries , chosen from a r and om sample of schools in a defined geographical area . FINDINGS Phase Three was completed a mean of 7 years after Phase One . Most centres showed a change in prevalence of 1 or more SE for at least one disorder , with increases being twice as common as decreases , and increases being more common in the 6 - 7 year age-group than in the 13 - 14 year age-group , and at most levels of mean prevalence . An exception was asthma symptoms in the older age-group , in which decreases were more common at high prevalence . For both age-groups , more centres showed increases in all three disorders more often than showing decreases , but most centres had mixed changes . INTERPRETATION The rise in prevalence of symptoms in many centres is concerning , but the absence of increases in prevalence of asthma symptoms for centres with existing high prevalence in the older age-group is reassuring . The divergent trends in prevalence of symptoms of allergic diseases form the basis for further research into the causes of such disorders This study was design ed to assess the effectiveness of a high-efficiency particulate air ( HEPA ) filter in alleviating  allergic respiratory symptoms . Thirty-two patients were studied who had symptomatic perennial rhinitis and /or asthma during the fall and winter months and had a positive skin test with house dust or house dust -- mite extract . An ENVIRACAIRE room air cleaner was placed in the bedroom for 8 weeks . In a r and om manner , the active filter was used for 4 weeks and a blank filter for 4 weeks . There was an average 70 % reduction in the particulate matter greater than or equal to 0.3 micron with the HEPA filter . In a double-blind design , results were assessed by analysis of the patients ' symptom/medication scores and subjective evaluation . For the total study , there was no difference in the total symptom/medication scores or individual symptom scores during the placebo and active-filter periods . Analysis of the last 2 weeks of each filter period in which respiratory infection was absent demonstrated definite differences in total and individual symptoms , suggesting active-filter benefit . Patients ' subjective responses also suggested benefit from the filter . The overall impression is that the HEPA filter can reduce allergic respiratory symptoms UNLABELLED The aim of this intervention study was to identify any health improvements in the upper and lower airways of office workers after the installation of local electrostatic air cleaners .  Eighty persons with airways symptoms were recruited and r and omly assigned to an intervention or control group . Half of the air cleaners had a non-functioning electrostatic unit . Both participants and field research ers were blinded to the group status . Subjective symptoms were recorded using a question naire , and indexes calculated for general , irritation and skin symptoms . Objective respiratory health indicators were recorded , with acoustic rhinometry and peak expiratory flow ( PEF ) meters . In the intervention group there was a decrease in mean dust concentration from 65 to 35 microg/m(3 ) , and a reduction from 57 to 47 microg/m(3 ) in the control group ( P < 0.05 for difference in decline ) . The reduction was observed for all particles sizes . The irritation and general symptom indices decreased in both groups , but there was no improvement in the intervention group , compared with the control group . Median PEF increased 3 ml/s in the intervention group , and decreased 4 ml/s in the control group . The adjusted odds ratio for an increase above the 70th percentile was 5.7 ( 95 % CI 1.0 - 32 ) . PRACTICAL IMPLICATION S Electrostatic air cleaners can reduce the dust concentration effectively in the office environment . Small , medium and large sized particles can be reduced by approximately 50 % , relatively most effectively for the respirable particles . However , the air cleaners tested in this study produced an annoying fan noise . Cleaning efficiency and noise data should be given consideration before installation . This experimental field study suggests that office workers with airways symptoms may benefit from installation of local electrostatic air cleaners N-(3,4-dimethoxycinnamoyl ) anthranilic acid ( N-5 ' ) , a new orally useable mast cell stabilizer , was investigated for its efficacy , safety and usefulness in the treatment of 302 patients with perennial nasal allergy by an intergroup , double-blind comparative test using disodium cromoglycate ( DSCG ) and an inactive placebo as control . The results indicated that N-5 ' , as a mild mast cell stabilizer , was comparable to DSCG in efficacy and minimum in side effect The efficacy of an air‐cleaning device equipped with a high efficiency particulate air ( HEPA ) filter ( without further avoidance measures ) was studied in patients allergic to house dust mite . The effects of the air‐cleaner on indoor Dermatophagoides sp. levels , symptom score and bronchial hyperresponsiveness in nine mite‐allergic patients were assessed using a cross‐over controlled study . No significant effect was demonstrated on indoor Dermatophagoides sp. levels when comparing the period of air‐cleaner activity ( 2 months ) with the control period ( 2 months ) . The Dermatophagoides sp. levels in the houses studied were lower than the risk level for asthmatic attacks , making it difficult to assess any effect on asthma ; however , neither bronchial hyperresponsiveness nor rhinitis symptom score were changed by air‐cleaner activity . During the trial period , however the mean level of Dermatophagoides sp. allergen in the houses changed spontaneously from 4.4 Hg/g ( mean level in the first 2 trial months ) to 1 . 75 μg/g of dust ( second 2 months ) ( P < 0.05 ) . Owing to this change , the mean rhinitis symptom score also decreased ( P < 0.05 ) , even if no significant correlation was demonstrated ( r = 0.4 P= 0.089 ) . HEPA filter air‐cleaners appear insufficient as substitutes for st and ard avoidance measures in mite allergic patients Inheritance and allergen exposure are key factors in the development and the course of atopic allergy , expressed as conjunctivitis , rhinitis , asthma or dermatitis . This study concerns the clinical significance of mite and mite‐allergen avoidance measures based on intensive cleaning with acaricide ( solidified benzylbenzoate ) added ( 10 dwellings ) , and without biocidal activity ( 10 other homes ) as a control in a double‐blind trial with matched pairs . Twenty subjects with persisting rhinitic complaints were selected . They lived in 20 different dwellings and were ail sensitized to pyroglyphid mites ; 12 of them were also sensitized to stored product miles ( Acari )  . Daily symptoms and medication score , guanine and dust exposure , total and mite‐specific IgE in serum , eosinophilia in the blood and in the nasal smear , intracutaneous tests with house dust mite and storage mite extracts were compared in both pairs and groups . Acarological data , physiochemical aspects and exposure assessment are discussed in detail elsewhere . Symptom scores dropped significantly , as did the total IgE and exposure to dust and mite products in the acaricidal cleaner treatment group . After 1 year , the daily symptoms median was 47 % ( P= 0.025 ) , total IgE was 38 % ( P=0.0049 ) , and exposure to dust and mite products ( guanine exposure ) was 53 % ( P= 0.0449 ) better or lower than in the controls . Intensive cleaning , without acaricidal treatment performed twice a year , result ed in clinical improvement in four out of 10 subjects , of whom none became free of complaints . In the Acarosan treatment group ( cleaning+ benzylbenzoate ) eight out of 10 subjcets improved , in three cases subjective symptoms disappeared . The conclusion is that mite avoidance in homes can be carried out successfully with a special acaricidal cleaning formulation Acarosan We report on the mechanisms , the environmental changes and patient compliance with regard to conventional and new dust and mite avoidance measures to prevent allergic symptoms caused by mite allergens , taking into account both allergen contamination and the developmental success of pyroglyph 
    Output:
    
House dust mite impermeable bedding as an isolated intervention is unlikely to offer clinical benefit .
Trials to date have on the whole been small and of poor method ological quality , making it difficult to offer any definitive recommendations on the role , if any , of house dust mite avoidance measures in the management of house dust mite sensitive perennial allergic rhinitis .
The results of these studies suggest that use of acaricides and extensive bedroom-based environmental control programmes may be of some benefit in reducing rhinitis symptoms and , if considered appropriate , these should be the interventions of choice .
Isolated use of house dust mite impermeable bedding is unlikely to prove effective