This is a list of diseases associated with fish,
Mycobacterium,
Erysipelothrix,
Campylobacter,
Aeromonas,
Vibrio,
Edwardsiella,
Escherichia,
Salmonella,
Klebsiella and
Streptococcus iniae.
from this web link, Zoonoses Associated with Fish (Including Aquarium Fish). The article does not recommend fish keeping for those with compromised immune system.
"Persons with specific medical conditions such as a chronic illness, immunodeficiency and pregnancy may be at higher risk of developing disease or complications from a zoonotic disease and should consult with their physician before working with animals."
Good night.
