[Occupational bio hazards: current issues]

Over the last decade, there was noted a large advancement of knowledge on living organisms and their products posing a potential occupational risk. Novel risk factors, often new to science, were identified, the role and significance of already known factors better comprehended, and occupational groups endangered by biological hazards more thoroughly recognized. Novel viruses and prions, emerging in different parts of the world, may pose a particular threat to health and life of health care workers, agriculture workers and veterinarians. A new coronavirus (SCoV) that evoked a rapid outbreak of disease described as severe acute respiratory syndrome (SARS) in the first half of 2003 may serve as an example. The disease was particularly common among health care workers. Previously discovered zoonotic viruses, Nipah virus in pigs and Hendra virus in horses, may be a cause of fatal encephalitis in animal farmers. Hantaviruses (Puumala, Hantaan, Sin Nombre and others) infecting field rodents may be a cause of hemorrhagic fever with renal syndrome (HFRS) or pulmonary syndrome (HPS) in farmers and laboratory workers. Prions responsible for inducing a zoonotic variant of Creutzfeldt-Jakob disease (vCJD) are considered to be a potential cause of work-related infections in agricultural and health care workers, however, this assumption has not as yet been supported by any conclusive evidence. In many countries, blood-borne occupational infections with hepatitis C virus (HCV) is the major epidemiological problem among health care workers, mostly because no vaccine against this virus has been produced to date. Vaccinations effectively restricted the number of occupational infections with hepatitis B virus (HBV), and work-related infections with human immunodeficiency virus (HIV) causing acquired immunodeficiency syndrome (AIDS) are very rare. Hazardous bioserosols, occurring in many work environments, pose an occupational health hazard of particular importance. Many new biological factors present in organic dusts that may induce work-related allergic and immunotoxic diseases among farmers and workers of the agricultural and wood industries have been identified. Droplet aerosols, which are generated from water, oils, oil-water emulsions and other liquids in various work environments, may contain infectious agents (Legionella spp.) as well as allergic and/or toxic agents. It has been shown that allergens and endotoxins produced by Gram-negative bacteria occurring in oil mist from metalworking fluids may cause occupational respiratory diseases in workers of the metallurgic industry.