Below is an instruction from Human. Write a response.
    ### Instruction:
    Who is at risk for Nocardiosis? ?
    ### Response:
    People with very weak immune (body defense) systems are at risk for getting nocardiosis. 
    
Several diseases and circumstances can cause the immune system to be weak. These include:
    
     - Diabetes
     - Cancer
     - HIV/AIDS
     - Pulmonary alveolar proteinosis (an illness that causes the air sacs of the lungs to become plugged)

    