Predictors of occupational sensitisation to grain dust allergens and changes in lung function among grain mill workers in Cape Town

Occupationally-related airway diseases, including asthma and chronic obstructive lung disease, have emerged as having substantial public health importance. The aim of this study was to identify the predictors of occupational sensitisation to grain dust allergens and changes in lung function among grain mill workers in Cape Town. There were two major objectives of the study. Firstly, to determine which of the following factors determine the distribution of serum ECP (eosinophilic cationic protein): age, gender, grain dust exposure, smoking status, atopy and sensitisation to workplace allergens. Secondly, to investigate the risk factors associated with the following outcomes: i) sensitisation to occupational allergens; ii) diagnosis of occupational asthma; iii) diagnosis of chronic obstructive airways disease; and iv) longitudinal changes in lung function. The risk factors studied included age, gender, smoking habits, occupational exposure, lung function status on baseline survey (1989), and allergic sensitisation assessed at follow up (1996). The methods employed involved a repeat measures cross-sectional design including a cohort followed up at different points over a seven year period. Survey instruments included a questionnaire, spirometry and allergy tests (phadiotop, RAST for wheat, rye, Lepidoglyphus destructor, Tyrophagus putrescentiae and Sitophilus granarius). The results indicated an association of grain dust with pulmonary function and allergic sensitisation to grain dust constituents. After adjusting for known confounders such as age, gender and smoking, significant associations were found between employment duration and both decrements in lung function and sensitisation to wheat grain. A decrement of 278 ml in FEY 1 and 328 ml in FYC was associated with occupational sensitisation to wheat (and rye). Increasing employment duration resulted in annual decrements of 18.3 ml in FEY1 and 23 ml in FYC for every year employed. The odds for developing occupational asthma was only mildly elevated (OR=l.35) with increasing employment duration. Age, however, was found to be protective (OR=0.85). Although we were unable to demonstrate a relationship between across-week changes in lung function, at inception, and rapid longitudinal lung function decline, our findings suggested that longitudinal change was related to the degree of airway obstruction at inception. Sensitisation to grain dust allergens was also found to be an independent predictor for FEY 1 and FYC. The prevalence of sensitisation was the highest for wheat (26.4%), followed by Tyrophagus putrescentiae (22.6%), rye (21.7%), Lepidoglyphus destructor (15.1 %) and Sitophilus granarius (15.1 %). Sensitisation to wheat was highly correlated with sensitisation to rye (r = 0.92) and so were Lepidoglyphus destructor and Tyrophagus putrescentiae (r = 0.85). Although a large proportion of the workforce ( 41.5 % ) were sensitised to occupational allergens, the prevalence of respiratory symptoms was between 15.6% and 23.9%. There were 16.7% of workers with health outcomes which fulfilled our criteria for occupational asthma. Atopic workers in our study had at least a nine-fold increased odds of becoming sensitised to grain dust allergens (OR: 8.9-74.7) and a two-fold increased odds of developing occupational asthma (OR= 1.9-84.9). Furthermore, the study found that smokers had a twofold increased odds of becoming atopic, thereby placing them at greater risk of developing respiratory health problems. The mean ECP in this population was 15.4 ug/1 (SD:2.5). Although 45.3% of the workers were atopic, it was not found to be predictor of elevated ECP levels. We were however able to demonstrate a significant association between ECP and sensitisation to grain allergens. Workers sensitised to wheat (positive RAST) had, on average, 1. 78 ug/1 higher ECP levels. The odds of having an elevated ECP (> 15 ug/1) increased by 2.9 for workers sensitised to wheat grain. In conclusion, the results of the study indicate that selection effects are in operation, demonstrating the health worker effect. The findings also suggest that across week reactions may be less sensitive than the across shift changes in predicting rapid longitudinal decline in lung function. While we were able to characterise the distribution of ECP according to exposure, we were however unable to define the temporal relationship between elevated between exposures, ECP and lung function outcomes due to limitations of the study design

Postgraduate Diploma in Occupational Health (DOH) - Module 3

Partly funded by Health OER Project (Hewlett Foundation)Chemistry bottles with liquid inside by zhouxuan12345678 shared under CC-BY-SA license.Designed to help teach doctors currently practising occupational health. The third module of a total of 8 modules for a two year part-time flexible distance learning course aimed primarily at medical doctors currently practising occupational health. It includes a residential block release component which consists of between 3 or 4 weeks over the two year cycle for practicum. While the course is aimed primarily at medical doctors currently practicing occupational health, it is also suited to selected graduates with appropriate University qualifications in relevant health sciences, as long as these individuals are currently practicing professionally in an occupational health setting. There are 8 modules (the two included here cover Occupational Hygiene and Epidemiology and Biostatistics). Each module has a theme around which the inputs are organised. Teaching inputs are intended to be non-didactic, and to allow student participation wherever possible. Candidates are expected to undertake substantial homework preparation and activities as well as self-directed learning. They will be expected to read widely and intensively around topics, and to provide teaching inputs themselves either directly or by way of specially structured interactive debates and role-play simulations. The content of these activities will include critical appraisal of the occupational health literature, project work, presentations by students as well as epidemiological, bio statistical, toxicological and occupational clinical assignments. Module 3 deals with basic occupational medicine and toxicology. Module 4 covers intermediate occupational medicine and toxicology, and Module 5 is advanced occupational medicine and toxicology

Розвиток поглядів про взаємозв'язок війни і миру, про «право народів» у елліністично-римській соціально-філософській думці

Античные мыслители лишь затронули вопрос об общем и вечном мире (в форме мечты, философского идеала идеального и гармонического государства), не находя способов примирения противоборствующих сторон, средств решения внутренних и внешних конфликтов.Античні мислителі лише порушили питання про загальний і вічний мир (у формі мрії, філософського ідеалу ідеальної і гармонічної держави), не знаходячи способів примирення протиборчих сторін, засобів вирішення внутрішніх і зовнішніх конфліктів

Health-Related Quality of Life (HRQoL) of Residents with Persistent Lower Respiratory Symptoms or Asthma Following a Sulphur Stockpile Fire Incident

Background: This study evaluated health-related quality of life (HRQoL) in residents with persistent lower respiratory symptoms (PLRS) or asthma six years after exposure to sulphur dioxide vapours emanating from an ignited sulphur stockpile. Methods:A cross-sectional study was carried out, using interview data collected at three time points (prior to, one- and six-years post incident), medical history, respiratory symptoms and HRQOL using the Medical Outcomes Study Form 36 (SF-36). Results: A total of 246 records, 74 with and 172 without PLRS or asthma, were analysed. The mean age was 42 (SD:12) years in the symptomatic group and 41 (SD:13) years in the asymptomatic group. Mean SF-36 scores were significantly lower for the symptomatic group in the Physical Functioning (24 vs. 39), Role—Physical (33 vs. 48) and General Health (GH) domains (24 vs. 37). Symptomatic residents experienced a significant decline in their Role—Physical (OR = 1.97; CI 1.09, 3.55) and GH (OR = 3.50; CI 1.39, 8.79) at year 6 compared to asymptomatic participants. Residents with co-morbid reactive upper airways dysfunction syndrome demonstrated stronger associations for GH (OR = 7.04; CI 1.61, 30.7) at year 1 and at year 6 (OR = 8.58; CI 1.10, 65.02). Conclusions:This study highlights the long-term adverse impact on HRQoL among residents with PLRS or asthma following a sulphur stockpile fire disaster

Characterization of Seafood Proteins Causing Allergic Diseases

[Extract] Food allergy is increasing at a faster rate than any other allergic disorder (Gupta et al., 2007). In the last few decades, a large movement toward healthier eating makes seafood one of the major foods consumed worldwide (Wild & Lehrer, 2005). Consequently, the international trade of seafood has been growing rapidly, which reflects the popularity and frequency of consumption worldwide. The United States has become the third largest consumer of seafood in the world, with 1.86 billion kg of crustaceans in 2007 (6.04 kg/capita/year)(Food and Agriculture Organisation, 2007). Since seafood ingestion can cause severe acute hypersensitivity reactions and is recognized as one of the most common food allergies, the increased production and consumption of seafood has resulted in more frequent health problems (Lopata & Lehrer, 2009; Lopata et al., 2010). Exposure to seafood can cause a variety of health problems, including gastrointestinal disorders, urticaria, immunoglobulin E (IgE)-mediated asthma and anaphylaxis (Bang et al., 2005; Lopata & Lehrer, 2009; Malo & Cartier, 1993; Sicherer et al., 2004; Wild & Lehrer, 2005)

Relationship between serum omega-3 fatty acid and asthma endpoints

Recent studies have highlighted the potential protective role of omega-3 polyunsaturated fatty acids (n-3 PUFA) in asthma. This study aimed at determining the association between seafood intake, serum PUFA composition and clinical endpoints of asthma in adults. A cross-sectional study of 642 subjects used the European Committee Respiratory Health Survey (ECRHS) questionnaire, skin prick tests, spirometry and methacholine challenge tests following ATS guidelines. Sera was analysed for n-3 and n-6 PUFA composition. Subjects had a mean age of 34 years, were largely female (65%) and 51% were current smokers. While 99% reported fish consumption, rock lobster, mussels, squid and abalone were also consumed less frequently. The prevalence of asthma symptoms was 11%, current asthma (ECRHS definition) was 8% and non-specific bronchial hyperresponsiveness (NSBH) was much higher (26%) In adjusted models the n-3 PUFAs 20:5 (EPA) and 22:5 (DPA) were significantly associated with a decreased risk of having NSBH. Total n-3 PUFA composition was associated with decreased NSBH risk (OR = 0.92), while high n-6 PUFA composition was associated with an increased risk (OR = 1.14)

A prospective cohort study on ambient air pollution and respiratory morbidities including childhood asthma in adolescents from the western Cape Province: study protocol

Background: There is evidence from existing literature that ambient air pollutant exposure in early childhood likely plays an important role in asthma exacerbation and other respiratory symptoms, with greater effect among asthmatic children. However, there is inconclusive evidence on the role of ambient air pollutant exposures in relation to increasing asthma prevalence as well as asthma induction in children. At the population level, little is known about the potential synergistic effects between pollen allergens and air pollutants since this type of association poses challenges in uncontrolled real life settings. In particular, data from sub-Sahara Africa is scarce and virtually absent among populations residing in informal residential settlements. Methods/design: A prospective cohort study of 600 school children residing in four informal settlement areas with varying potential ambient air pollutant exposure levels in the Western Cape in South Africa is carried-out. The study has two follow-up periods of at least six-months apart including an embedded panel study in summer and winter. The exposure assessment component models temporal and spatial variability of air quality in the four study areas over the study duration using land-use regression modelling (LUR). Additionally, daily pollen levels (mould spores, tree, grass and weed pollen) in the study areas are recorded. In the panel study asthma symptoms and serial peak flow measurements is recorded three times daily to determine short-term serial airway changes in relation to varying ambient air quality and pollen over 10-days during winter and summer. The health outcome component of the cohort study include; the presence of asthma using a standardised ISAAC questionnaire, spirometry, fractional exhaled nitric-oxide (FeNO) and the presence of atopy (Phadiatop). Discussion: This research applies state of the art exposure assessment approaches to characterize the effects of ambient air pollutants on childhood respiratory health, with a specific focus on asthma and markers of airway inflammation (FeNO) in South African informal settlement areas by considering also pollen counts and meteorological factors. The study will generate crucial data on air pollution and asthma in low income settings in sub-Sahara Africa that is lacking in the international literature

Occupational allergy associated with saltwater bony fish processing in South Africa.

The South African seafood industry employs over 28,000 mainly seasonal women workers involved predominantly in bony fish processing activities. The aim of this study was to determine the risk of developing work-related asthma and dermatitis during fish processing. A cross-sectional study of 594 workers in two factories involved in fish canning (pilchard) and fishmeal processing (anchovy and pilchard) was undertaken. All workers were evaluated using interviewer-administered questionnaires, skin prick tests with common airborne and fish allergen extracts, and pulmonary function including methacholine challenge tests. A subgroup of workers (n = 241) underwent skin examination and patch tests. Time-integrated environmental sampling using a thoracic fraction sampler collected 198 personal samples for total particulate mass, protein and specific fish antigen determinations. A novel ELISA-inhibition assay using polyclonal antibodies was developed for this purpose. Multivariate logistic and Cox proportional hazards models were used in the data analysis. Results of environmental samples demonstrated a wide variation in mean (arithmetic) airborne concentrations of thoracic particulate 0.61 mg/m 3 (0--11.3), total protein 0.89 mug/m3 (0--11.5), pilchard antigen 150 ng/m3 (0--15,973) and anchovy antigen 552 ng/m3 (0--75,748) levels. All four exposure metrics were consistently elevated for fishmeal production. Ambient pilchard and anchovy antigen levels were more strongly correlated with each other than total thoracic particulate and fish antigen concentrations. Common work-related symptoms reported included ocular-nasal (26%), asthma (16%) and skin symptoms (14%). The prevalence of atopy (positive skin prick test to one or more common allergens) was 36% with 7% sensitized to fish and 26% having nonspecific bronchial hyperresponsiveness. The prevalence of fish-related rhinoconjunctivitis was slightly higher (2.6%) than probable occupational asthma (1.8%), protein contact dermatitis and urticaria (Type I allergy) (1--2%), and allergic contact dermatitis due to fish (Type IV allergy) (1--3%). Atopy and smoking were important host factors related to fish sensitization. Workers with recurrent skin symptoms were twice as likely to be sensitized to fish. In Cox proportional hazards models, having work-related asthma symptoms was associated with a two-fold increased odds of being exposed to pilchard antigen concentrations >30 ng/m3 at the time when symptoms occurred. In conclusion, workers involved in bony fish processing (canning and fishmeal production) are at increased risk of developing work-related asthma symptoms due to inhalation of aerosols containing fish allergens.Ph.D.Health and Environmental SciencesImmunologyOccupational safetyPublic healthUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/123995/2/3106356.pd