Health Status and Needs of Latino Dairy Farmworkers in Vermont

ABSTRACT

Vermont is a new Latino destination where many Spanish-speaking migrants have found work on dairy farms. One hundred twenty Latino workers were surveyed on 59 Vermont dairy farms to develop a demographic profile and evaluate their self-assessed health status and barriers to care. The study found, similar to other studies, the majority of workers were young, male Mexicans. However, the workers in this study, as compared to others, originated farther south in Mexico and there were significant regional differences in educational attainment. Workers defined health in terms of their ability to work and the majority believed themselves to be in good health. The majority felt that moving to the United States has not changed their health status. The most common health issue reported was back/neck pain, followed by dental and mental health issues. Workers are both physically and linguistically isolated and reported isolation as the most challenging aspect of dairy farm work. Fear of immigration law enforcement was the primary barrier to care. Community-based initiatives, including partnerships with colleges and universities, outreach to farm employers and the adoption of “bias-free policing” are strategies that can increase access to health care for Latino dairy farmworkers in the United States.     

A Systematic Search and Review of Questionnaires Measuring Individual psychosocial Factors Predicting Return to Work After Musculoskeletal and Common Mental Disorders

Purpose Individual psychosocial factors are crucial in the return to work (RTW) process of workers with musculoskeletal disorders (MSDs) and common mental disorders (CMDs). However, the quality and validity of the questionnaires used to measure these factors have rarely been investigated. The present systematic search and literature review aims at identifying, categorizing, and evaluating the questionnaires (measurement tools) used to measure individual psychosocial factors related to the perception of the personal condition and motivation to RTW that are predictive of successful RTW among workers with MSDs or CMDs. Methods Through a systematic search on PubMed, Web of Science, and PsycINFO library databases and grey literature, we identified the individual psychosocial factors predictive of successful RTW among these workers. Then, we retrieved the questionnaires used to measure these factors. Finally, we searched for articles validating these questionnaires to describe them exhaustively from a psychometric and practical point of view. Results: The review included 76 studies from an initial pool of 2263 articles. Three common significant predictors of RTW after MSDs and CMDs emerged (i.e., RTW expectations, RTW self-efficacy, and work ability), two significant predictors of RTW after MSDs only (i.e., work involvement and the self-perceived connection between health and job), and two significant predictors of RTW after CMDs only (i.e., optimism and pessimism). We analyzed 30 questionnaires, including eight multiple-item scales and 22 single-item measures. Based on their psychometric and practical properties, we evaluated one of the eight multiple-item scales as questionable and five as excellent. Conclusions: With some exceptions (i.e., self-efficacy), the tools used to measure individual psychosocial factors show moderate to considerable room for improvement.

     

Prevalence of musculoskeletal disorders among immigrant Latino farmworkers and non-farmworkers in North Carolina

This paper evaluates the variability in the prevalence of epicondylitis, rotator cuff syndrome, low back pain, and lower extremity pathology among immigrant Latino farmworkers and non-farmworkers. Data were collected from a study among 272 farmworkers and non-farmworkers. Participants were recruited in eastern and central North Carolina. A physical examination was conducted by trained physicians. Prevalence of musculoskeletal disorders (MSDs) among Latino manual workers is high compared with other workers in similar occupations. Non-farmworkers (49%) had a higher prevalence of MSDs than farmworkers (35%). Epicondylitis (20.2%) and rotator cuff syndrome (19.1%) were most prevalent. Age was found to be significant among those who had epicondylitis (adjusted odds ratio [AOR] = 1.04) and lower extremity pathology (AOR = 1.07). Latino immigrant manual workers have high prevalence of MSDs. Further studies are needed to identify possible factors that make these populations more vulnerable to MSDs.     

Ache, pain, and discomfort: the reward for working with many cows and sows?

The main purpose of the study was to investigate the prevalence of perceived symptoms of musculoskeletal disorders (MSD) among workers on large-scale dairy and pig farms in Sweden (herd size more than 300 cows and 450 sows) and to identify potential risk factors in the development of MSD. A study based on questionnaires was carried out among 42 workers on 10 large dairy farms and among 37 workers on 10 large pig farms in Southern Sweden during the autumn of 2002. Most importantly, the study showed that 86% of the dairy workers and 78% of the pig workers reported some kind of MSD during a period of 12 months prior to the study. The most frequently reported MSD among both the dairy and the pig workers were in the "upper extremities" (52% and 62%, respectively) especially in the shoulders and in "the back" (60% and 57%, respectively) especially in the lower back. Furthermore, being of short stature, doing repetitive work, working in awkward positions and being exposed to dust were significant risk factors in having MSD among the workers in this study. Thus, working with many cows and sows on large-scale farms in Sweden can be considered as a high risk job with regard to MSD.     

Physically demanding workloads and the risks of musculoskeletal disorders in homecare workers in the USA

Although musculoskeletal disorders (MSDs) are prevalent among homecare workers, little is known about the MSD risk factors. This study investigated whether physically demanding workloads among homecare workers are related to MSDs, especially in neck, shoulder and back pain. Data were taken from two waves of a random sample (June to December 2003 and December 2003 to February 2004). The sample included 1643 homecare workers at Wave 1 and 1198 homecare workers at Wave 2, respectively. A basic telephone interview and 30 minutes computer‐assisted interview were performed for homecare workers in Wave 1 and Wave 2. The prevalence of neck, shoulder and back MSDs was assessed at Wave 1 and Wave 2 using the Nordic questionnaire of musculoskeletal symptoms. The incidence of MSDs at 6 months was estimated at Wave 2 using only those who were in the asymptomatic reference group at Wave 1 as the denominator. At Wave 1, back MSDs were the most prevalent (10.2%), followed by neck (9.6%) and shoulder (7.1%) MSDs. After 6 months, the incidence of neck MSDs was the highest (7.0%), followed by back (6.4%) and shoulder (4.8%) MSDs. Physical demands of work were assessed using items developed from focus groups of workers. When compared with asymptomatic workers, those with MSDs showed a dose–response effect for physical job demands. After controlling for age, psychosocial demands and social support on‐the‐job, physical demands among homecare workers were significantly associated with an excessive odds of neck, shoulder and back MSDs incident at 6 months (odds ratios of 1.14–1.17 for each unit increase on a physical demand scale). Our study shows that the physical demands of work are a significant risk factor for MSDs among homecare workers. Considering the high physical demands among homecare workers, the finding in this study clearly indicates that practical intervention strategies should be implemented to protect homecare workers from exposure to MSD risk factors.     

Stress and Burnout Among Finnish Dairy Farmers

Psychosocial risks among farmers have increasingly been examined because of the ongoing changes in agriculture, such as restructuring of the industry, transition from family farming towards entrepreneurship, and climate change. The aims of the study were to determine the stressors, prevalence of stress and burnout, and variables associated with these symptoms among Finnish dairy farmers. In total 265 respondents completed a postal survey; their average age was 48 years, 44% were females and 56% males. The farms of the survey sample were larger (54 field hectares, 29 cows) than an average farm in Finland (37 hectares, 24 cows) in 2010. The most common stressors were external, such as “agricultural policy of the EU” (European Union) and “the treatment of farmers in society and the media.” In addition, common stressors were related to farm and work, e.g., “amount of work,” unpredictability, and “animal diseases.” The prevalence of stress (42%) was found to have increased compared with earlier studies and was greater than among the general working population. All respondents as a group were classified as having slight symptoms of burnout, and one tenth (9%) of dairy farmers had experienced severe burnout. Stressors related to the workload and health were associated with stress and burnout symptoms. Also, a poor economic situation and loneliness were related to stress. Burnout correlated with a tie stall barn type and with a farm not being involved in the milk production record system. Factors protecting against burnout included positive features of the work and living environment. The study revealed changes during the past decade and new features of the well-being at work on dairy farms in Finland.     

Health status and needs of Latino dairy farmworkers in Vermont

Vermont is a new Latino destination where many Spanish-speaking migrants have found work on dairy farms. One hundred twenty Latino workers were surveyed on 59 Vermont dairy farms to develop a demographic profile and evaluate their self-assessed health status and barriers to care. The study found, similar to other studies, the majority of workers were young, male Mexicans. However, the workers in this study, as compared to others, originated farther south in Mexico and there were significant regional differences in educational attainment. Workers defined health in terms of their ability to work and the majority believed themselves to be in good health. The majority felt that moving to the United States has not changed their health status. The most common health issue reported was back/neck pain, followed by dental and mental health issues. Workers are both physically and linguistically isolated and reported isolation as the most challenging aspect of dairy farm work. Fear of immigration law enforcement was the primary barrier to care. Community-based initiatives, including partnerships with colleges and universities, outreach to farm employers and the adoption of "bias-free policing" are strategies that can increase access to health care for Latino dairy farmworkers in the United States.     

Work characteristics and upper extremity disorders in female dental health workers

Many dental health workers suffer from musculoskeletal disorders in the upper extremities. In addition to ergonomic factors, psychosocial work characteristics have been linked to musculoskeletal disorders. The present cross-sectional study aimed at investigating how musculoskeletal disorders in the upper extremities (UED) and occupational position are related to work characteristics and general health problems in female dental health workers. Questionnaire data from dentists, dental hygienists and dental nurses (N=945) showed that 81% reported UED. Multivariate analysis of variance showed that dentists reported the highest levels of physical load and fatigue whereas dental nurses reported the lowest levels of influence at work. Irrespective of position, those with UED considered their physical and psychosocial work environment and their own health to be significantly poorer than did those without UED. A hierarchical multiple regression showed that the physical load of dentistry was most strongly related to UED. Despite improvements to the ergonomics and physical work environment of dentistry, it is concluded that female dental health workers are still at high risk of developing UED.     

Growth of the Spanish-Speaking Workforce in the Northeast Dairy Industry

ABSTRACT

The Spanish-speaking proportion of the Northeast dairy industry workforce is believed to be increasing. This study quantifies the extent of this increase over time in New York, Pennsylvania, and Vermont, and compares demographics between English- and Spanish-speaking workers. A total of 293 farms were followed for 21 months via telephone. The proportion of the Spanish-speaking dairy workforce was measured. Differences in demographic characteristics were assessed. The proportion of Spanish-speaking workers increased linearly for both large and small farms. The rate of increase was much greater on large farms. Linear models predicted that 53.2% of the large and 18.1% of the small farm workforce would be Spanish speaking within 5 years. Spanish-speaking workers worked significantly longer weeks than their English-speaking counterparts. The Occupational Safety and Health Administration (OSHA) monitoring cutoff for number of employees is currently 10. Consequently, the increase in the proportion of Spanish-speaking workers in dairy, who have been shown to work more hours per week, is likely to result in fewer workers per farm. This could have implications for farms currently under OSHA regulations based on having 10 or more workers, because farms with workers working longer hours per week will employ fewer workers overall. In addition, according to section 330 of the Public Health Service Act, these workers do not currently meet the migrant farmworker definition that would qualify them to receive primary health services from federally funded migrant health centers. New legislation is needed to formally qualify this growing indigent population to receive healthcare via channels that are currently available to migrant and seasonal farmworkers.     

Job Resources and Work Engagement among Finnish Dairy Farmers

Objectives: The aims of this study were to examine job resources, work engagement and Finnish dairy farmers’ preferences concerning methods to enhance overall well-being while working on farms.

Methods: A postal survey yielded 265 completed questionnaires from 188 dairy farms. The sample was assessed as representative of Finnish dairy farmers. Exploratory factor analysis and a linear mixed model were utilized during the data analyzing process.

Results: The variables lowering work engagement were stressors related to the workload and problems with health. Elevated work engagement was associated with the factors work with farm animals and family. The most important resource variables were “child or children,” “own family,” and “animal health.” Female dairy farmers considered resource variables related to the family, love, and work with cattle as significantly more important than male dairy farmers. Male dairy farmers experienced higher work engagement and, concerning the dimensions, especially higher dedication and absorption than male respondents in a reference sample of workers in difference occupations. A sustainable farm economy and the possibility to have a holiday period were the most important methods to improve overall well-being on dairy farms.

Conclusion: The results indicate that the family, working with cattle, healthy farm animals, a reasonable workload, and a sustainable farm economy have the capacity to create positive impacts on well-being among dairy farmers. Well-being on farms is a part of sustainable food production.     

A cross-sectional study of risk factors for musculoskeletal symptoms in the workplace using data from the General Social Survey (GSS)

OBJECTIVE: Assessments of potential risk factors for musculoskeletal disorders (MSDs) from large, national study populations using personal interviews are critical to our understanding of exposure-response relationships. To address this need, we analyzed two outcome measures--self-reported back pain and upper extremity pain--from the quality of work life (QWL) module of the General Social Survey (GSS). We investigated several individual, psychosocial, and physical factors for their relationship to these outcome measures. METHODS: The study population included US adults, noninstitutionalized, English-speaking, aged 18 years or older, and employed at least part time (>or=20 hr/wk). Final sample size was 1484 workers. RESULTS: Variables of physical exposure significantly increased the risk of both low back pain and upper extremity pain. Multiple injuries and some psychosocial factors were associated with MSDs, and there was an additive effect on risk of MSDs with exposure to both physical exposure and work stress. CONCLUSIONS: A relationship between physical loads and musculoskeletal disorders was indicated by the results, which will enable creating a database for tracking reports of MSDs in the US working population.     

International Perspectives on Psychosocial Working Conditions,Mental Health,and Stress of Dairy Farm Operators

ABSTRACT

Dairy farm operators—farmers, workers, and family members—are faced with many demands and stressors in their daily work and these appear to be shared across countries and cultures. Dairy operators experience high psychosocial demands with respect to a hard work and production ethos, economic influences, and social and environmental responsibility. Furthermore, both traditional and industrial farms are highly dependent on external conditions, such as weather, fluctuating markets, and regulations from government authorities. Possible external stressors include disease outbreaks, taxes related to dairy production, and recent negative societal attitudes to farming in general. Dairy farm operators may have very few or no opportunities to influence and control these external conditions, demands, and expectations. High work demands and expectations coupled with low control and lack of social support can lead to a poor psychosocial work environment, with increased stress levels, ill mental health, depression, and, in the worst cases, suicide. Internationally, farmers with ill mental health have different health service options depending on their location. Regardless of location, it is initially the responsibility of the individual farmer and farm family to handle mental health and stress, which can be of short- or long-term duration. This paper reviews the literature on the topics of psychosocial working conditions, mental health, stress, depression, and suicide among dairy farm operators, farm workers, and farm family members in an international perspective.     

Associations between neck musculoskeletal complaints and work related factors among public service computer workers in Kaunas

Objectives

Information technologies have been developing very rapidly, also in the case of occupational activities. Epidemiological studies have shown that employees, who work with computers, are more likely to complain of musculoskeletal disorders (MSD). The aim of this study was to evaluate associations between neck MSD and individual and work related factors.

Materials and Methods

The investigation which consisted of two parts — a questionnaire study (using Nordic Musculoskeletal questionnaire and Copenhagen Psychosocial Questionnaire) and a direct observation (to evaluate ergonomic work environment using RULA method) was carried out in three randomly selected public sector companies of Kaunas. The study population consisted of 513 public service office workers.

Results

The survey showed that neck MSDs were very common in the investigated population. The prevalence rate amounted to 65.7%. According to our survey neck MSDs were significantly associated with older age, bigger work experience, high quantitative and cognitive job demands, working for longer than 2 h without taking a break as well as with higher ergonomic risk score. The fully adjusted model working for longer than 2 h without taking a break had the strongest associations with neck complaints.

Conclusion

It was confirmed, that neck MSDs were significantly associated with individual factors as well as conditions of work, therefore, preventive actions against neck complaints should be oriented at psychosocial and ergonomic work environment as well as at individual factors.     

职业因素对汽车制造业工人肌肉骨骼疾患影响的研究

目的了解作业场所职业病危害因素与工效学危险因素等对工人几个主要身体部位肌肉骨骼疾患（MSDs）的影响。方法选取南方3家汽车生产制造企业,采用分层、整群抽样的方法,随机从冲压、焊装、涂装、总装、树脂、质检等生产部门中抽取1个班组的生产工人作为调查对象,对其进行问卷调查,收集个人一般情况、职业病危害因素接触情况、典型不良劳动姿势与活动的暴露情况及肩臂部、手部、下背部的阳性症状。影响肌肉骨骼症状发生的单因素分析采用X^2检验,多因素分析采用logistic回归。结果共调查794名工人,其中男性765人,女性29人,平均年龄为（23．34±4．52）岁,工龄中位数2年,其文化程度以中专及以上为主（97．8％）。车企工人总体的MSDs年患率分别为下背部47．0％、肩臂部42．9％、手腕／手掌41．3％。不同工种间不同身体部位MSDs的年患率的差异均有统计学意义（均P〈0．01）,其中肩臂部、手彬手掌的年患率以焊装工的最高,下背部的年患率以总装工的最高。多因素分析结果显示,背前屈〉30°的工作（OR=1．691）等2项与下背部阳性症状年患率有关,手部高力量大角度屈伸的上肢重复活动（OR=1．685）等3项与肩臂阳性症状年患率有关,手部高力量高度重复活动（OR=1．956）等4项与手腕／手掌的阳性症状年患率有关。结论被调查的汽车制造企业工人下背部、肩臂部、手部3个身体部位MSDs的患病情况较突出,各部位的MSDs年患率主要与不良的工作姿势、活动及搬举负荷强度等工效学不良因素有关,需针对其采取有效的控制措施。     

Psychosocial work environment among immigrant and Danish cleaners

Introduction  

Non-Western cleaners have been shown to have poorer health than their Danish colleagues. One reason could be a poorer psychosocial work environment. However, it is unknown if differences in self-reported psychosocial work environment exist between non-Western and Danish workers within the same social class. The aim of this study was to investigate such differences among cleaners with the hypothesis that the non-Western compared with Danish cleaners would report a generally poorer psychosocial work environment.     

Prevalence and impact of musculoskeletal disorders in New Zealand nurses, postal workers and office workers

Objectives: To describe the prevalence, characteristics and impact of musculoskeletal disorders (MSDs) in New Zealand nurses, postal workers and office workers.
Methods: A postal survey asked participants about MSDs, (low back, neck, shoulder, elbow, wrist/hand or knee pain lasting longer than one day), and demographic, physical and psychosocial factors. Nurses were randomly selected from the Nursing Council database, postal workers from their employer's database and office workers from the 2005 electoral roll.
Results: The response rate of potentially eligible participants was 58% (n=443). Participants were aged 20–59 years; 86% were female. Over the 12 months prior to the survey 88% of respondents had at least one MSD lasting longer than a day and 72% reported an MSD present for at least seven days. Of the 1,003 MSDs reported, 18% required time off work and 24% required modified work duties. In the month prior to the survey 17% of MSDs made functional tasks difficult or impossible. Low back, neck and shoulder pain prevalence did not differ by occupation. Postal workers had the highest prevalence of elbow and wrist/hand pain; nurses of knee pain.
Conclusions: The high prevalence of MSDs among these workers indicates that they are indeed in 'at risk' occupations. In each occupational group MSDs encompass a range of anatomical sites, however the overall pattern of MSDs differs by occupation. MSDs have a significant impact on activities at work and home.
Implications: Primary and secondary prevention strategies should encompass a range of anatomical sites and specifically target different occupational groups.     

肩部肌肉骨骼疾患及危险因素

肌肉骨骼疾患(MSDs)是一类常见的工作有关疾病,发病率较高,严重影响劳动者的身心健康和工作质量。引起MSDs的危险因素众多、复杂,查阅近年来国内外文献,本文针对肩部MSDs的危险因素进行综述,探讨职业因素、社会心理因素和个体因素在MSDs的发生发展中的作用。以期从加强个人体育锻炼、定期体检、改善工作环境、合理安排劳动组织等方面加以预防。     

Systematic comparative content analysis of 17 psychosocial work environment questionnaires using a new taxonomy

Background: Many questionnaires have been developed to measure how psychosocial characteristics are perceived in a work environment. But the content validity of these questionnaires has rarely been questioned due to the absence of a reference taxonomy for characteristics of work environments.

Objectives: To propose an exhaustive taxonomy of work environment characteristics involved in psychosocial risks and to apply this taxonomy to questionnaires on workplace psychosocial factors.

Methods: The taxonomy was developed by categorizing factors present in the main theoretical models of the field. Questionnaire items most frequently cited in scientific literature were retained for classification.

Results: The taxonomy was structured into four hierarchical levels and comprises 53 categories. The 17 questionnaires analyzed included 927 items: 59 from the “physical environment” category, 116 from the “social environment” category, 236 from the “work activity” category, 255 from the “activity management” category, and 174 from the “organizational context” category.

Conclusions: There are major content differences among analyzed questionnaires. This study offers a means for selecting a scale on the basis of content.     

Work Safety Culture of Youth Farmworkers in North Carolina: A Pilot Study

Objectives. We analyzed aspects of the behavioral, situational, and psychological elements of work safety culture of hired youth farmworkers in North Carolina.Methods. Data were from interviewer-administered questionnaires completed with 87 male and female hired farmworkers aged 10 to 17 years in North Carolina in 2013. We computed means, SDs, and Cronbach α values for the perceived work safety climate and safety perception summary scores.Results. Hired youth farmworkers in North Carolina described a negative work safety culture. Most engaged in unsafe general and unsafe work behaviors, few received training, and many were sexually harassed at work. They had mixed safety attitudes and knew that their employment was precarious. They reported a poor perceived work safety climate characterized by the perception that their supervisors “are only interested in doing the job fast and cheaply.” However, we could not detect statistically significant associations between work safety culture and injuries among these farmworkers.Conclusions. Increased scrutiny of agriculture as a suitable industry for workers as young as 10 years and additional regulations to protect hired youth farmworkers, if not to remove them from this environment, are warranted. Additional research is needed.Youths employed as agricultural workers in the United States experience high rates of injury and mortality.1–4 Many youths are employed in agricultural work on their family’s farm, but many other youths are hired farmworkers working on commercial farms. Current regulations allow youths as young as 14 years to be employed as hired farmworkers without parental permission; youths aged 10 to 13 years can be employed as hired farmworkers with parental permission.5–7 Youths employed in agriculture can work with sharp tools, machinery, and pesticides, as well as do the strenuous tasks of planting, cultivating and harvesting crops, and working with large animals.Most hired youth farmworkers in the United States are Latino, and often they are either immigrants from Mexico and Central American countries or the US-born children of immigrant farmworker parents.8,9 An unknown number of youth farmworkers are unaccompanied minors who migrate for agricultural employment but are not accompanied by a parent.10,11 Hired youth farmworkers share the same vulnerabilities as adult farmworkers, including low wages, few or no benefits, few regulatory protections, hazardous work, discrimination, and limited access to health care.12–14 Youth farmworkers are especially vulnerable to occupational injuries because of their smaller size, lesser strength, and greater surface-to-volume ratio compared with adults; their developing neurological and reproductive systems; and their lack of maturity and experience. Few studies have addressed factors affecting the occupational health and safety of youths working on farms, with fewer studies focused on hired youth farmworkers.Work safety culture is an important aspect of workplace safety.15 On the basis of Bandura’s theory of reciprocal determinism,16,17 Cooper15 argued that safety culture includes behavioral, situational, and psychological elements, thereby encompassing many different aspects of the work environment. Behavioral elements include observable safety and risk behaviors. Situational elements include safety management programs and actions. Psychological elements include subjective assessments of safety. For example, work safety climate, a worker’s perceptions of how an employer values safety over production,18,19 has been related to adverse health outcomes, including musculoskeletal discomfort and working while injured or ill, among adult farmworkers.20Westaby and Lee21 applied the work safety culture model in a longitudinal analysis of injuries among Future Farmers of America members. They found that a behavioral measure, dangerous risk taking, was positively associated with injuries; that a psychological measure, safety consciousness, was inversely related to injuries; but that a situational measure, safety knowledge, had a positive rather than a negative association with injuries. They suggested that this last, counterintuitive result may be explained by workers being placed in more dangerous environments for which they are provided greater safety information.Only a few elements of work safety culture of hired youth farmworkers have been addressed in the literature. For example, among the behavioral elements, general risk behavior (e.g., not wearing a helmet when riding a motorcycle) and work risk behavior (e.g., working with power tools, working with toxic substances) are positively associated with the incidence of injuries among youths working on farms.22–24 Shipp et al.25 reported that few (19%) adolescent farmworkers in Texas received pesticide safety training, a situational element. Parental attitude toward safety is another situational element that has been examined for youths working on farms.26 Having a risky attitude, a psychological element, is associated with the incidence of injuries among youths working on farms.22–24Greater effort is needed to document work safety culture of all youths working on farms; this effort is particularly important for hired youth farmworkers because they are more vulnerable than youths working on family farms. In our analysis, we used data from a pilot study to describe aspects of the behavioral, situational, and psychological elements of work safety culture of hired youth farmworkers in North Carolina.     

Occupational exposure to poultry and prevalence of antibodies against Marek''s disease virus and avian leukosis retroviruses.

OBJECTIVES: To compare the prevalence of antibodies against Marek's disease herpes virus (MDV) and against avian leukosis viruses type C (ALV) in groups of workers exposed to poultry and in unexposed groups. METHODS: Antibodies directed against avian viral proteins were detected by enzyme linked immunosorbent assay in 549 subjects. Exposure to chickens was high in two subgroups: farmers on intensive chicken farms and workers at chicken slaughterhouses. One subgroup, traditional farmers on dairy or pig farms with poultry, had moderate exposure to poultry. Another subgroup, farmers and slaughterhouse workers on quail farms, had high exposure to quails. Three subgroups were not exposed to chickens: farmers on dairy or pig farms without poultry, workers at cattle slaughterhouses, and white collar workers. Also, MDV antibodies were tested after serum sample adsorption with chicken antigens in 134 serum samples. RESULTS: The prevalence of antibodies against MDV was significantly higher in the exposed subgroups than in unexposed groups (odds ratio (OR) 6.17; 95% confidence interval (95% CI) 3.91-9.75). No association was found between seroprevalence and age. However, higher prevalence was found among women and was related to duration of exposure to chickens. The concentration of antibodies from a few subjects remained very high after adsorption. Significant differences between the men and women were found for the prevalence of antibodies for ALV but were not related to exposure to chickens. CONCLUSIONS: The prevalence of antibodies against MDV was significantly higher among workers exposed to chickens and was related to sex and duration of exposure. The higher prevalence of antibodies against avian oncogenic viruses found among women compared with men may be induced by differences in exposure or by genetic factors. The meaning of these high titres could be related to the presence of MDV in humans. Because the involvement of animal oncogenic viruses in human cancer is indicated by epidemiological and some experimental studies, the integration of viral DNA in human cells needs to be investigated.