Returning to work after transplantation is a much-discussed topic today, especially as a measure to avoid permanent work disability. Many transplant patients regain their ability to work 2-6 months after transplantation. However, returning to work should not endanger their health. This means that occupational risks such as occupational exposure to Aspergillus spores must be evaluated. We evaluated the community-acquired aspergillosis risk and in particularly the occupational aspergillosis risk, using the example of a 39-year-old construction worker immunosuppressed after renal transplantation. On one hand the risk is linked to the exposure to microorganisms that the individual is likely to be subjected to, and on the other hand to the factors that modify his state of susceptibility or resistance to these infectious agents. The necessity of immunosuppressive therapy after transplantation elevates the aspergillosis risk, especially 1-6 months after transplantation. There are many professions in which exposure to Aspergillus spores can occur. The risk of acquiring aspergillosis at work exists, but is not quantifiable today. Nevertheless, the risk should be minimized during the period of vulnerability by preventive measures such as restriction of certain activities, changing work methods and reorganizing the work day to adapt to the risk, and wearing personal protective equipment, as well as attention to information about aspergillosis risk and about the likelihood of exposure in the patient's professional and leisure activities. [Authors]