Bacillus anthracis contamination and inhalational anthrax in a mail processing and distribution center.

AIMS: Four inhalational anthrax cases occurred in a large mail processing and distribution center in Washington, DC, after envelopes containing Bacillus anthracis spores were processed. This report describes the results of sampling for B. anthracis spores during investigations conducted in October and December 2001. METHODS AND RESULTS: Wet swabs, wet wipes, vacuum sock, and air-filter samples were collected throughout the facility to characterize the extent of building contamination. The results showed widespread contamination of B. anthracis spores, particularly associated with one delivery bar code sorter (DBCS) machine that had sorted the spore-containing envelopes and an area where the envelopes were handled by postal workers. Spore concentrations decreased as distance from the DBCS machine increased, but spores were widely dispersed into surrounding areas. CONCLUSION: The spatial distribution of culture positive samples was closely related to the work areas of the inhalational anthrax cases and supported epidemiological evidence that the workers became ill from exposure to B. anthracis spores in areas where the contaminated envelopes had travelled. SIGNIFICANCE AND IMPACT OF THE STUDY: The results of this investigation were used to guide decontamination efforts and provided baseline spore concentrations for follow-up measurements after the building had been cleaned. Implementing methods to reduce aerosolization and dispersion of dust within the facility would reduce postal workers' potential exposures to bioterrorism agents.

Epidemiology of work-related musculoskeletal disorders.

Musculoskeletal disorders are common in the United States. Although precise estimates are not available, most researchers agree that exposure to a combination of work place risk factors is a major contributor to these disorders. Along with personal factors (age, gender, etc.). Epidemiologic studies of workers have associated these disorders with many work-place physical and psychosocial factors. Specific physical factors associated with these disorders include intense, repeated, or sustained exertions, awkward, sustained, or extreme postures of the body, insufficient recovery time, vibration, and cold temperatures. Specific examples of work-place psychosocial factors include monotonous work, time pressure, high work load, lack of peer support, and a poor supervisor-employee relationship.

Musculoskeletal disorders among visual display terminal users in a telecommunications company.

The relationship between workplace factors and work-related upper extremity musculoskeletal disorders (UE disorders) was assessed in a cross-sectional study of 533 telecommunication employees utilizing video display terminals (VDTs). Cases of UE disorders were defined using symptom questionnaires and physical examinations. Data on demographics, individual factors (medical conditions and recreational activities), work organization and practices, and psychosocial aspects of work, including electronic performance monitoring (EPM), were obtained by questionnaire. Associations between workplace factors and UE disorders were assessed by multiple logistic models generated for each of the four UE areas (neck, shoulder, elbow, hand/wrists). One-hundred and eleven (22%) participants met our case definition for UE disorders. Probable tendon-related disorders were the most common (15% of participants). Probable nerve entrapment syndromes were found in 4% of participants. The hand/wrist was the area most affected, 12% of participants. The following variables had associations in the final models (p < 0.05) with at least one of the four UE disorders, although the strength of these associations were modest. Non-white race, a diagnosis of a thyroid condition (self-reported) use of bifocals at work, and seven psychosocial variables (fear of being replaced by computers, increasing work pressure, surges in workload, routine work lacking decision-making opportunities, high information processing demands, jobs which required a variety of tasks and lack of a production standard) were associated with UE disorders. This study indicates that work-related UE musculoskeletal disorders are relatively common among telecommunication workers who use VDTs, and adds to the evidence that the psychosocial work environment is related to the occurrence of these disorders.

Management of upper extremity cumulative trauma disorders.

1. Elements critical to a successful medical management program include cumulative trauma disorder (CTD) surveillance, conditioning and rehabilitation programs, and familiarity with OSHA recordkeeping requirements, in addition to recognition, evaluation, and treatment. 2. Occupational health care providers (HCPs) can identify high risk departments, production lines, or jobs through the passive and/or active surveillance systems. 3. The HCP should perform a CTD evaluation of employees assigned to jobs with known ergonomic hazards or areas found to have CTD problems by the surveillance system. These evaluations should consist of a medical and occupational history, and a physical examination of the upper extremities. 4. The treatment algorithm emphasizes that a) symptomatic employees need follow up to determine the effectiveness of the prescribed treatments, b) employees with severe symptoms, positive physical findings, or disorders resistant to treatment need to be referred to a physician for further evaluation, and c) conservative therapy deserves an adequate trial before surgical intervention is contemplated.

Ergonomic analysis to characterize task constraint and repetitiveness as risk factors for musculoskeletal disorders in telecommunication office work.

A modified activity analysis procedure was devised to quantify the presence of two task attributes identified in previous research as contributing to an increase in work demands and ergonomic hazards. The purpose of this study was to develop an exposure index based on the presence of two task attributes. The utility of this job activity analysis will, of course, be determined by the extent to which workers with varying degrees of muscular pain and discomfort correspond to the risk exposure group we have described. The results of both the medical and psychological assessments of the workers--contained in the final HETA report--will be used to assess the utility of our method and determine whether the task attributes of constraint and repetitiveness contribute to the onset of cumulative trauma disorders among clerical workers.

An epidemic of dermatitis at a large construction site.

During 6 months in 1986, an epidemic of dermatitis occurred among more than 5600 workers at a single large construction site in the United States. To identify its cause, we used the monthly nurses' log of visits to the medical facility to characterize the outbreak by person, place, and time. Follow-up studies included a survey of carpenters and skin testing of laboratory animals. Workers were more than twice as likely to visit the medical facility for a skin-related complaint in 1986 compared with 1985 (relative rate [RR] = 2.6, 95% confidence interval [CI] 2.2-3.2). Carpenters experienced the greatest increased risk (RR = 9.7, 95% CI 5.5-17.3). We found a strong association between dermatitis and handling of fire-retardant lumber and plywood. Carpenters working only with fire-retardant lumber had a rate of dermatitis 4 times that of carpenters who worked exclusively with untreated wood (RR = 3.6, 95% CI 1.5-8.6). Carpenters who occasionally worked with fire-retardant lumber and plywood were at moderate risk (RR = 2.18, 95% CI 0.7-6.7). Although laboratory tests showed that phosphate compounds could be leached with water from the fire-retardant wood, an extract of these phosphates did not irritate the skin of laboratory animals. We concluded the epidemic was a result of handling fire-retardant lumber but could not identify the specific chemical agent. In view of the observed association, construction workers should be advised to handle this material with caution, especially in high temperature and humidity.