Risks of new-onset allergic sensitization and airway inflammation after early age swimming in chlorinated pools

Rationale

Irritant chlorination products in swimming pools can cause respiratory problems in swimmers but their possible implication in allergies development is still unclear.

Objectives

To assess prospectively whether early-life attendance at chlorinated pools increases the risks of IgE sensitization and of airways inflammation later during childhood.

Methods

We conducted a two-year prospective study among 196 kindergarten children (mean age of 5.7 years, 54% of boys). We measured exhaled nitric oxide (eNO) and aeroallergen-specific IgE in nasal mucosa. Parents completed a questionnaire about the child's health, chlorinated pool attendance and potential confounders.

Main Results

Ever swimming at indoor or outdoor chlorinated pools before the age of three years was associated with higher odds for new-onset IgE sensitization to house dust mite (adjusted odds ratio [aOR] 2.93, 95% confidence interval [CI] 1.14–7.55) and for new-onset increased eNO (>15 ppb; aOR, 4.54, 95% CI 1.48–13.9). For both outcomes, aORs increased dose-dependently with time spent in chlorinated pools with values reaching, respectively, 3.60 (95% CI 1.21–10.7) and 5.92 (95% CI 1.72–20.5) when the cumulative pool attendance exceeded 60 h These risks appeared independently of each other, of parental history of allergies and of pre-existing diseases, including eczema, which at baseline was more prevalent in early swimmers (aOR, 2.91; 95% CI 1.23–6.89). Such associations were not seen with IgE sensitization to pollen or cat allergens.

Conclusion

Attendance at chlorinated swimming pools in early life is associated with higher risks of new-onset airways inflammation and IgE sensitization to house dust mite, independently of other risk factors.     

Occupational Exposure to Crystalline Silica at Alberta Work Sites

Although crystalline silica has been recognized as a health hazard for many years, it is still encountered in many work environments. Numerous studies have revealed an association between exposure to respirable crystalline silica and the development of silicosis and other lung diseases including lung cancer. Alberta Jobs, Skills, Training and Labour conducted a project to evaluate exposure to crystalline silica at a total of 40 work sites across 13 industries. Total airborne respirable dust and respirable crystalline silica concentrations were quite variable, but there was a potential to exceed the Alberta Occupational Exposure Limit (OEL) of 0.025 mg/m³ for respirable crystalline silica at many of the work sites evaluated. The industries with the highest potentials for overexposure occurred in sand and mineral processing (GM 0.090 mg/m³), followed by new commercial building construction (GM 0.055 mg/m³), aggregate mining and crushing (GM 0.048 mg/m³), abrasive blasting (GM 0.027 mg/m³), and demolition (GM 0.027 mg/m³). For worker occupations, geometric mean exposure ranged from 0.105 mg/m³ (brick layer/mason/concrete cutting) to 0.008 mg/m³ (dispatcher/shipping, administration). Potential for GM exposure exceeding the OEL was identified in a number of occupations where it was not expected, such as electricians, carpenters and painters. These exposures were generally related to the specific task the worker was doing, or arose from incidental exposure from other activities at the work site. The results indicate that where there is a potential for activities producing airborne respirable crystalline silica, it is critical that the employer include all worker occupations at the work site in their hazard assessment. There appears to be a relationship between airborne total respirable dust concentration and total respirable dust concentrations, but further study is require to fully characterize this relationship. If this relationship holds true, it may provide a useful hazard assessment tool for employers by which the potential for exposure to airborne respirable silica at the work site can be more easily estimated.     

接尘工人血清中抗核因子、人抗中性粒细胞浆抗体水平的检测

摘要:目的:探讨接尘工人血清中自身免疫抗体抗核因子(ANA)、人抗中性粒细胞浆抗体(cANCA)的表达水平和意义.方法:以119例接尘工人为研究组,以86例健康者为对照,采集外周静脉血,应用ELISA试剂盒检测血清中自身免疫抗体ANA、cANCA的表达水平.结果:接尘工人血清中ANA、cANCA的含量和阳性率均高于对照...     

高房价、高地价与房产税的深层思考

当前我国经济社会中面临的突出问题,莫过于高房价给人们带来的困惑与不安。而且有不少人把高房价归咎于政府的高地价。殊不知,高房价的最直接原因,是市场上房产供求比例的严重失衡。与其说是高地价引发高房价,不如说是高房价拉动高地价。面对国务院多次加强对房产的宏观调控,不仅没有把过高的房价降下来,反而出现越调房价越高的尴尬局面。房产税重在完善财税体制和调节居民收入分配,它虽具有调节房产的需求功能,但对其可能带来的降价效应不应期望过高。加大保障房供有量和抑制投资与投机需求,才是抑制房价高涨的重要对策。     

Correlation between inhalant allergen-specific IgE and pulmonary function in children with asthma

Sensitization to aeroallergens is associated with diminished lung function in adults. Little has been studied on the relationship between the inhalant allergen-specific IgE and pulmonary function in asthmatic children. This study was focused on four major inhalant allergens found in Korea, including Dermatophagoides pteronyssinus (Der p.), Dermatophagoides farinae (Der f.), and Alternaria- and German cockroach-specific IgEs, with evaluation of pulmonary function in relation to the amount of allergens. The parents or legal guardians of participants enrolled in this study gave informed consent. Fifty-five asthmatic patients and 48 nonasthmatic children were included. The amounts of specific IgE for the four specified inhalant allergens were determined by employing the CAP system FEIA. Forced expiratory volume in 1 sec (FEV(1))/forced vital capacity (FVC), FEV(1), and forced expiratory flow between 25% and 75% of FVC (FEF(25-75)) of subjects were evaluated through pulmonary function tests. In the asthmatic group, FEV(1), FEV(1)/FVC, and FEF(25-75) were significantly reduced (P < 0.05): reduction in FEV(1) (r = -0.44) and FEF(25-75) (r = -0.33) in association with the Der f.-specific allergen, and reduction in FEV(1) (r = -0.37) and FEF(25-75) (r = -0.34) in association with the Der p.-specific allergen, were observed. However, there was no significant correlation with German cockroach and Alternaria allergen. In the control group, no significant correlation was detectable between the allergen-specific IgE titers and the results of pulmonary function tests. In asthmatic patients, Der p.- and Der f.-specific IgEs, and not German cockroach and Alternaria, seem to play a considerable role in reduced pulmonary function among asthmatic children.     

To the hospital and back home again: a nurse practitioner-based transitional care program for hospitalized homebound people

Homebound older adults may receive suboptimal care during hospitalizations and transitions home or to postacute settings. This 2-year study describes a nurse practitioner (NP)-led transitional care program embedded within an existing home-based primary care (HBPC) program. The transitional care pilot program was designed to improve coordination and continuity of care, reduce readmissions, garner positive provider feedback, and demonstrate financial benefits through shorter length of stay, lower cost of inpatient stay, and better documentation of patient complexity. A detailed mixed-methods evaluation was conducted to characterize the hospitalized homebound population and investigate provider feedback and program feasibility, effectiveness, and costs. Length of stay (LOS), case-mix index, and admission-related financial costs were compared before and after the intervention using a pre-post design. Structured focus groups were conducted with inpatient and primary care providers to collect feedback on the usefulness of and satisfaction with the program. The program improved communication between home-based primary care providers and inpatient providers of all disciplines and facilitated the timely and accurate transfer of critical patient information. The intervention failed to decrease hospital LOS and readmission rate significantly for people who were hospitalized. The financial implications were reassuring, although future studies are necessary. This model of a NP-led program may be feasible for enhancing inpatient management and transitional care for older adults in HBPC programs and should be considered to augment the HBPC care model.     

Changes in house design reduce exposure to malaria mosquitoes

House design may affect an individual's exposure to malaria parasites, and hence to disease. We conducted a randomized-controlled study using experimental huts in rural Gambia, to determine whether installing a ceiling or closing the eaves could protect people from malaria mosquitoes. Five treatments were tested against a control hut: plywood ceiling; synthetic-netting ceiling; insecticide-treated synthetic-netting ceiling (deltamethrin 12.5 mg/m2); plastic insect-screen ceiling; or the eaves closed with mud. The acceptability of such interventions was investigated by discussions with local communities. House entry by Anopheles gambiae, the principal African malaria vector, was reduced by the presence of a ceiling: plywood (59% reduction), synthetic-netting (79%), insecticide-treated synthetic-netting (78%), plastic insect-screen (80%, P < 0.001 in all cases) and closed eaves (37%, ns). Similar reductions were also seen with Mansonia spp., vectors of lymphatic filariasis and numerous arboviruses. Netting and insect-screen ceilings probably work as decoy traps attracting mosquitoes into the roof space, but not the room. Ceilings are likely to be well accepted and may be of greatest benefit in areas of low to moderate transmission and when used in combination with other malaria control strategies.     

额尔齐斯河下游北湾地区人房和猪舍内蚊虫季节消长观察

目的研究蚊虫危害十分严重的新疆额尔齐斯河下游的北湾地区,蚊虫在人房和猪舍内的季节消长。方法用诱蚊灯诱蚊1夜调查人房内的蚊虫密度,用电动吸蚊器吸捕15m in调查猪舍内蚊虫密度,从4月开始,每月上、中、下旬三次直至蚊虫活动消失。结果人房内蚊虫从4月中旬出现,米赛按蚊(45%),刺扰伊蚊(54%)为优势蚊种,蚊虫季节分布为三峰型,7月上旬为活动最高峰,9月上旬蚊虫消失;猪舍蚊虫出现较晚,5月上旬出现,刺扰伊蚊(90.7%)为优势蚊种,季节分布呈双峰型,7月为活动最高峰,9月上旬消失。结论6~7月是北湾地区人房及猪舍内的蚊虫活动高峰。     

A comparison of use of a pyrethroid either for house spraying or for bednet treatment against malaria vectors

In an intensely malarious area in north-east Tanzania, microencapsulated lambdacyhalothrin was used in four villages for treatment of bednets (provided free of charge) and in another four villages the same insecticide was used for house spraying. Another four villages received neither intervention until the end of the trial but were monitored as controls. Bioassays showed prolonged persistence of the insecticidal residues. Light traps and ELISA testing showed reduction of the malaria vector populations and the sporozoite rates, leading to a reduction of about 90% in the entomological inoculation rate as a result of each treatment. Collections of blood fed mosquitoes showed no diversion from biting humans to biting animals. Incidence of re-infection was measured by weekly monitoring of cohorts of 60 children per village, after clearing pre-existing infection with chlorproguanil-dapsone. The vector control was associated with a reduction in probability of re-infection per child per week by 54–62%, with no significant difference between the two vector control methods. Cross-sectional surveys for fever, parasitaemia, haemoglobin and weight showed association of high parasitaemia with fever and anaemia and beneficial effects of each intervention in reducing anaemia. However, passive surveillance by resident health assistants showed no evidence for reduced prevalence of fever or parasitaemia. Net treatment consumed only about one sixth as much insecticide as house spraying and it was concluded that the former intervention would work out cheaper and nets were actively demanded by the villagers, whereas spraying was only passively assented to.