Preliminary epidemiological study of latent tuberculosis in Mexican agricultural workers in the Niagara region, Canada

It is well documented that the majority of Tuberculosis (TB) cases diagnosed in Canada are related to foreign-bom persons from TB high-burden countries. The Canadian seasonal agricultural workers program (SAWP) operating with Mexico allows migrant workers to enter the country with a temporary work permit for up to 8 months. Preiimnigration screening of these workers by both clinical examination and chest X-ray (CXR) reduces the risk of introducing cases of active pulmonary TB to Canada, but screening for latent TB (LTBI) is not routinely done. Studies carried out in industrialized nations with high immigration from TBendemic countries provide data of lifetime LTBI reactivation of around 10% but little is known about reactivation rates within TB-endemic countries where new infections (or reinfections) may be impossible to distinguish from reactivation. Migrant populations like the SAWP workers who spend considerable amounts of time in both Canada and TBendemic rural areas in Mexico are a unique population in terms of TB epidemiology. However, to our knowledge no studies have been undertaken to explore either the existence of LTBI among Mexican workers, the probability of reactivation or the workers' exposure to TB cases while back in their communities before returning the following season. Being aware of their LTBI status may help workers to exercise healthy behaviours to avoid TB reactivation and therefore continue to access the SAWP. In order to assess the prevalence of LTBI and associated risk factors among Mexican migrant workers a preliminary cross sectional study was designed to involve a convenience sample of the Niagara Region's Mexican workers in 2007. Research ethics clearance was granted by Brock University. Individual questionnaires were administered to collect socio-demographic and TB-related epidemiological data as well as TB knowledge and awareness levels. Cellular immunity to M tuberculosis was assessed by both an Interferon-y release assay (lGRA), QuantiFERON -TB Gold In-Tube (QFf™) and by the tuberculin skin test (TSn using Mantoux. A total of 82 Mexican workers (out of 125 invited) completed the study. Most participants were male (80%) and their age ranged from 22 to 65 years (mean 38.5). The prevalence of LTBI was 34% using TST and 18% using QFTTM. As previously reported, TST (using ~lOmm cut-off) showed a sensitivity of 93.3% and a specificity of 79.1 %. These findings at the moment cannot predict the probability of progression to active TB; only longitudinal cohort studies of this population can ascertain this outcome. However, based on recent publications, lORA positive individuals may have up to 14% probability of reactivation within the next two years. Although according to the SA WP guidelines, all workers undergo TB screening before entering or re-entering Canada, CXR examination requirements showed to be inconsistent for this population: whereas 100% of the workers coming to Canada for the first time reported having the procedure done, only 31 % of returning participants reported having had a CXR in the past year. None of the participants reported ever having a CXR compatible with TB which was consistent with the fact that none had ever been diagnosed with active pulmonary TB and with only 3.6% reporting close contact with a person with active TB in their lifetime. Although Mexico reports that 99% of popUlation is fully immunized against TB within the first year of age, only 85.3% of participants reported receiving BOC vaccine in childhood. Conversely, even when TST is not part of the routine TB screening in endemic countries, a suqDrisingly high 25.6% reported receiving a TST in the past. In regards to TB knowledge and awareness, 74% of the studied population had previous knowledge about (active) TB, 42% correctly identified active TB symptomatology, 4.8% identified the correct route of transmission, 4.8% knew about the existence of LTBI, 3.6% knew that latent TB could reactivate and 48% recognized TB as treatable and curable. Of all variables explored as potential risk factors for LTBI, age was the only one which showed statistical significance. Significant associations could not be proven for other known variables (such as sex, TB contact, history of TB) probably because of the small sample size and the homogeneity of the sample. Screening for LTBI by TST (high sensitivity) followed by confirmation with QFT''"'^ (high specificity) suggests to be a good strategy especially for immigrants from TB high-burden countries. After educational sessions, workers positive for LTBI gained greater knowledge about the signs and symptoms of TB reactivation as well as the risk factors commonly associated with reactivation. Additionally, they were more likely to attend their annual health check up and request a CXR exam to monitor for TB reactivation.

Vitamin D status and latent tuberculosis infection : a preliminary study in a group of healthy Mexican agricultural workers

Vitamin D metabolites are important in the regulation of bone and calcium homeostasis, but also have a more ubiquitous role in the regulation of cell differentiation and immune function. Severely low circulating 25-dihydroxyvitamin D [25(OH)D] concentrations have been associated with the onset of active tuberculosis (TB) in immigrant populations, although the association with latent TB infection (LTBI) has not received much attention. A previous study identified the prevalence of LTBI among a sample of Mexican migrant workers enrolled in Canada's Seasonal Agricultural Workers Program (SA WP) in the Niagara Region of Ontario. The aim of the present study was to determine the vitamin D status of the same sample, and identify if a relationship existed with LTBI. Studies of vitamin D deficiency and active TB are most commonly carried out among immigrant populations to non-endemic regions, in which reactivation of LTBI has occurred. Currently, there is limited knowledge of the association between vitamin D deficiency and LTBI. Entry into Canada ensured that these individuals did not have active TB, and L TBI status was established previously by an interferon-gamma release assay (IGRA) (QuantiFERON-TB Gold In-Tube®, Cellestis Ltd., Australia). Awareness of vitamin D status may enable individuals at risk of deficiency to improve their nutritional health, and those with LTBI to be aware of this risk factor for disease. Prevalence of vitamin D insufficiency among the Mexican migrant workers was determined from serum samples collected in the summer of 2007 as part of the cross sectional LTBI study. Samples were measured for concentrations of the main circulating vitamin D metabolite, 25(OH)D, with a widely used 1251 250HD RIA (DiaSorin Inc.®, Stillwater, MN), and were categorized as deficient «37.5 nmoI/L), insufficient (>37.5 nmollL, < 80 nmol/L) or sufficient (2::80 nmoI/L). Fisher's exact tests and t tests were used to determine if vitamin D status (sufficiency or insufficiency) or 25(OH)D concentrations significantly differed by sex or age categories. Predictors of vitamin D insufficiency and 25(OH)D concentrations were taken from questionnaires carried out during the previous study, and analyzed in the present study using multiple regression prediction models. Fisher's exact test and t test was used to determine if vitamin D status or 25(OH)D concentration differed by LTBI status. Strength of the relationship between interferongamma (IFN-y) concentration (released by peripheral T cells in response to TB antigens) and 25(OH)D concentration was analyzed using a Spearman correlation. Out of 87 participants included in the study (78% male; mean age 38 years), 14 were identified as LTBI positive but none had any signs or symptoms of TB reactivation. Only 30% of the participants were vitamin D sufficient, whereas 68% were insufficient and 2% were deficient. Significant independent predictors of lower 25(OH)D concentrations were sex, number of years enrolled in the SA WP and length of stay in Canada. No significant differences were found between 25(OH)D concentrations and LTBI status. There was a significant moderate correlation between IFN-y and 25(OH)D concentrations ofLTBI-positive individuals. The majority of participants presented with Vitamin D insufficiency but none were severely deficient, indicating that 25(OH)D concentrations do not decrease dramatically in populations who temporarily reside in Canada but go back to their countries of origin during the Canadian winter. This study did not find a statistical relationship between low levels of vitamin D and LTBI which suggests that in the presence of overall good health, lower than ideal levels of 2S(OH)D, may still be exerting a protective immunological effect against LTBI reactivation. The challenge remains to determine a critical 2S(OH)D concentration at which reactivation is more likely to occur.

Copper levels in buccal cells of vineyard workers engaged in various activities

Objectives: Copper-based compounds have been used as agricultural fungicides for many years. Their use in Australia is escalating with increase in the scale of planting and associated pest problems. The objective of this study was to identify viticulture activities associated with high exposure to foliage sprays. It would be determined if occupational exposure of vineyard workers to copper-based sprays was associated with raised body copper levels through analysis of saliva and buccal cells.

Methods: The activities of six vineyard workers from four vineyards in the Yarra Valley Victoria, Australia, were monitored over a period of 2 years. During this period, workers carried out seasonal activities, including fungicide spraying, canopy management, and tractor operation. Saliva and buccal cells from workers were collected and analysed for copper levels that were then correlated with the different types of vineyard activity.

Results: The buccal cells of vineyard workers exposed to copper through seasonal activities including fungicide spraying, canopy management, and tractor operation contained copper levels of 0.87, 1.24, and 0.95 ng Cu per 106 cells, respectively. This was up to 10-fold higher than the copper levels in buccal cells from the control subjects (0.1 ng Cu per 106). Copper levels in buccal cells from workers participating in other viticulture activities such as shoot thinning, bunch counting, and disbudding were not significantly different from those of control subjects. The levels of copper in saliva samples of both workers undertaking any vineyard activity and control subjects were below the level of detection.

Conclusions: Seasonal activities undertaken in vineyards that involved direct contact with copper, in particular canopy management, fungicidal spraying, and tractor operation were associated with high copper levels in buccal cells of workers. This indicates that copper derived from copper-based fungicidal compounds is accumulated within body cells. The lack of detectable copper levels in saliva suggests that the route of transport of copper into buccal cells is not through saliva. The results indicate potential adverse health risks associated with use of copper fungicide. Recommendations are made in relation to the precautions that should be taken in relation to use of copper sprays and to validate buccal cells as an indicator of body copper status.

Welcome workers from 'bipolar' Pacific

The article focuses on the comments concerning the Australian government's Pacific Seasonal Worker Pilot Scheme in Papua New Guinea. It has been perceived that it could not help the employment problems in the country and other countries included. Its objective has been questioned by Opposition Leader Brendan Nelson. Many believed that few people to be included in the scheme would only make an insignificant difference to the problems of under-and unemployment with which they are faced.

Foraging Activity and Seasonal Food Preference of Linepithema micans (Hymenoptera: Formicidae), a Species Associated With the Spread of Eurhizococcus brasiliensis (Hemiptera: Margarodidae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Learning Curves of Temporary Workers in Manual Order Picking Activities

Person-to-stock order picking is highly flexible and requires minimal investment costs in comparison to automated picking solutions. For these reasons, tradi-tional picking is widespread in distribution and production logistics. Due to its typically large proportion of manual activities, picking causes the highest operative personnel costs of all intralogistics process. The required personnel capacity in picking varies short- and mid-term due to capacity requirement fluctuations. These dynamics are often balanced by employing minimal permanent staff and using seasonal help when needed. The resulting high personnel fluctuation necessitates the frequent training of new pickers, which, in combination with in-creasingly complex work contents, highlights the im-portance of learning processes in picking. In industrial settings, learning is often quantified based on diminishing processing time and cost requirements with increasing experience. The best-known industrial learning curve models include those from Wright, de Jong, Baloff and Crossman, which are typically applied to the learning effects of an entire work crew rather than of individuals. These models have been validated in largely static work environments with homogeneous work contents. Little is known of learning effects in picking systems. Here, work contents are heterogeneous and individual work strategies vary among employees. A mix of temporary and steady employees with varying degrees of experience necessitates the observation of individual learning curves. In this paper, the individual picking performance development of temporary employees is analyzed and compared to that of steady employees in the same working environment.

Use of intranet and other interventions to increase influenza vaccination among health care workers

Influenza (the flu) is a serious respiratory illness that can cause severe complications, often leading to hospitalization and even death. Influenza epidemics occur in most countries every year, usually during the winter months. Despite recommendations from the Centers for Disease Control and Prevention (CDC) and efforts by health care institutions across the United States, influenza vaccination rates among health care workers in the United States remain low. How to increase the number of vaccinated health care workers is an important public health question and is examined in two journal articles included here. ^ The first journal article evaluates the effectiveness of an Intranet intervention in increasing the proportion of health care workers (HCWs) who received influenza vaccination. Hospital employees were required go to the hospital's Intranet and select "vaccine received," "contraindicated," or "declined" from the online questionnaire. Declining employees automatically received an online pop-up window with education about vaccination; managers were provided feedback on employees' participation rates via e-mail messages. Employees were reminded of the Intranet requirement in articles in the employee newsletter and on the hospital's Intranet. Reminders about the Intranet questionnaire were provided through managers and newsletters to the HCWs. Fewer than half the employees (43.7%) completed the online questionnaire. Yet the hospital witnessed a statistically significant increase in the percentage of employees who received the flu vaccine at the hospital – 48.5% in the 2008-09 season as compared to 36.5%, 38.5% and 29.8% in the previous three years (P < 0.05). ^ The second article assesses current interventions employed by hospitals, health systems and nursing homes to determine which policies have been the most effective in boosting vaccination rates among American health care workers. A systematic review of research published between January 1994 and March 2010 suggests that education is necessary but not usually sufficient to increase vaccine uptake. Education about the flu and flu vaccines is most effective when complemented with easy access and making the vaccine free, although this combination may not be sufficient to achieve the desired vaccination levels among HCWs. The findings point toward adding incentives for HCWs to get vaccinated and requiring them to record their vaccination status on a declination/consent form – either written or electronic. ^ Based on these findings, American health care organizations, such as hospitals, nursing homes, and long-term care facilities, should consider using online declination forms as a method for increasing influenza vaccination rates among their employees. These online forms should be used in conjunction with other policies, including free vaccine, mobile distribution and incentives. ^ To further spur health care organizations to adopt policies and practices that will raise influenza vaccination rates among employees, The Joint Commission – an independent, not-for- profit organization that accredits and certifies more than 17,000 health care organizations and programs in the United States – should consider altering its standards. Currently, The Joint Commission does not require signed declination forms from employees who eschew vaccination; it only echoes the CDC's recommendations: "Health care facilities should require personnel who refuse vaccination to complete a declination form." Because participation in Joint Commission accreditation is required for Medicare reimbursement, action taken by the Joint Commission to require interventions such as mandatory declination/consent forms might result in immediate action by health care organizations to follow these new standards and lead to higher vaccination rates among HCWs.^ 1“Frequently Asked Questions for H1N1 and Seasonal Influenza.” The Joint Commission - Infection Control: http://www.jointcommission.org/PatientSafety/InfectionControl/h1n1_faq.htm. ^

Acceptability of pandemic A(H1N1) influenza vaccination by Essential Community Workers in 2010 Alicante (Spain), perceived seriousness and sources of information

Objective. Describe acceptability of pandemic A(H1N1) influenza vaccination by Essential Community Workers (ECWs) from Alicante province (Spain) in January 2010. Evaluate the correlation with attitudes, beliefs, professional advice and information broadcasted by media. Method. In this cross-sectional study, face-to-face interviews were conducted with 742 ECWs to assess their attitudes towards vaccination against the pandemic influenza strain. A multivariable regression model was made to adjust the Odds Ratios (ORs). Results. Some ECWs reported having been vaccinated with seasonal vaccine, 21.5% (95%IC 18.6–24.9); only 15.4% (95%IC 12.8–18.4) with the pandemic one. ECWs vaccinated regularly against seasonal flu (OR 5.1; 95%IC 2.9–9.1), those who considered pandemic influenza as a severe or more serious disease than seasonal flu (OR 3.8; 95%IC 2.1–6.7) and those who never had doubts about vaccine safety (OR 3.7; 95%IC2.1–6.7) had a better acceptance of pandemic vaccine. Finally, 78.7% (95%IC 75.1–81.4) had doubts about pandemic vaccine's effectiveness. Conclusion. The vast amount of information provided by the media did not seem to be decisive to prevent doubts or to improve the acceptability of the vaccine in ECWs. Professional advice should be the focus of interest in future influenza vaccination campaigns. These results should be taken into account by health authorities.

Seasonal variations in surface metabolite composition of Fucus vesiculosus and Fucus serratus sampled at outer Kiel Fjord (August 2012 - July 2013)

The chemical composition of surface associated metabolites of two Fucus species (Fucus vesiculosus and Fucus serratus) was analysed by means of gas chromatography-mass spectrometry (GC-MS) to describe temporal patterns in chemical surface composition. Method: The two perennial brown macroalgae F. vesiculosus and F. serratus were sampled monthly at Bülk, outer Kiel Fjord, Germany (54°27'21 N / 10°11'57 E) over an entire year (August 2012 - July 2013). Per month and species six non-fertile Fucus individuals were collected from mixed stands at a depth of 0.5 m under mid water level. For surface extraction approx. 50 g of the upper 5-10 cm apical thalli tips were cut off per species. The surface extraction of Fucus was performed according to the protocol of de Nys and co-workers (1998) with minor modifications (see Rickert et al. 2015). GC/EI-MS measurements were performed with a Waters GCT premier (Waters, Manchester, UK) coupled to an Agilent 6890N GC equipped with a DB-5 ms 30 m column (0.25 mm internal diameter, 0.25 mM film thickness, Agilent, USA). The inlet temperature was maintained at 250°C and samples were injected in split 10 mode. He carrier gas flow was adjusted to 1 ml min-1. Alkanes were used for referencing of retention times. For further details (GC-MS sample preparation and analysis) see the related publication (Rickert et al. submitted to PLOS ONE).

Down the aisle : the effects of technological change on retail workers skills

Reconfiguration of corporate structures and the retailer-supplier interface in the retail industry have restructured product markets and supply chains, as well as supermarket employment, over the past decade or so (Baret, Lehndorff & Sparks 2000; du Gay 1996). Various studies have examined the consequent changes in labour usage practices within supermarkets or superstores (Baret et al. 2000; Marchington 1995; Penn & Wirth 1993; Sparks 1992; Dawson, Findlay & Sparks 1987, 1986). Commonly, this literature explores the interplay between shifts in the structure of the labour market, broader societal trends and retailers’ employment strategies. One study found that domestic and gender dimensions, accompanied by industrial relations regimes, exert considerable influence on patterns of labour usage (Baret et al. 2000). However, while the types of labour usage and the drivers of changes to labour usage patterns have attracted significant academic attention, research has largely overlooked the ways in which the nature of supermarket work has evolved as a result of changing technology, which effectively bolsters managerial prerogative, and which has affected the skill levels of workers in the industry (Marchington 1995).

Union strategies in representing ‘new workers’ : the case of UK retail union

The purpose of this paper is to explore the changing nature of employee voice through trade union representation in the retail industry. The retail industry is a major employer in the UK and is one of the few private sector service industries with union representation (Griffin et al 2003). The requisite union: the Distributive and Allied Workers (USDAW) union is one of the biggest unions in the country. However, the characteristics of the industry provide unique challenges for employee voice and representation including: high labour turnover; high use of casual, female and student labour; and, variable levels of union recognition (Reynolds et al 2005). Irrespective of these challenges, any extension of representation and organisation by unions in the retail sector is inherently valuable, socially and politically, given that retail workers are often categorised as vulnerable, due to the fact that they are among the lowest paid in the economy, sourced from disadvantages labour markets and increasingly subject to atypical employment arrangements (Broadbridge 2002; Henley 2006; Lynch 2005; Roan 2003).

Management and organisational barriers in the acquisition of computer usage skills by mature age workers

Aim: To investigate workplace cultures in the acquisition of computer usage skills by mature age workers. Methods: Data were gathered through focus groups conducted at job network centres in the Greater Brisbane metropolitan region. Participants who took part were a mixture of workers and job-seekers. Results: The results suggest that mature age workers can be exposed to inappropriate computer training practices and age-insensitive attitudes towards those with low base computer skills. Conclusions: There is a need for managers to be observant of ageist attitudes in the work place and to develop age-sensitive strategies to help mature age workers learn computer usage skills. Mature age workers also need to develop skills in ways which are practical and meaningful to their work.