Dear Oceanic I understand that you are worrying about visiting your Dad who is going to have Chemotherapy in case he he gets infected as your recovering from Typhoid fever. To answer your quiry please let me tell you some thing about typhoid fever. Typhoid fever is caused by the germ called salmonella and spreads and trasmitted by infected food and water cotaminated by stool of an infected person. It can spreads by poor hygine sanitation and handling of food or drink also by flying insects feeding on infected faecies and contaminating food and drinks. Taking regorous steps of careful handwashing after going to the toilet and before food handling, maintaining good sanitation care, treating drinking water with clorine spread of tyhhoid fever can be avoided.So long you are not handling food or water and taking all those precausions as I described there is no need to warry about.