Thanks for your reply, It was alot of help.
It is not such a silly question. His immune system will be suppressed.
If she is ill, then yes, she can make him ill. Normally, a doctor will advise him/them about how he can be exposed to people. Usually a spouse is ok as they are pretty used to each others germs but going out to a store may be a no no. He is going to be very tired, and pretty sleepy while the chemo is working.
There may be a situation where the WBC or other blood components may drop too low and in that case, he may have to be hospitalized in isolation for a while. Sometimes people taking chemo wear face masks to prevent infections like air-borne colds etc. Keeping hands clean, the house and all will have to be done. He may need to sleep in a separate bed, a hospital type bed, which can be rented, if necessary. I would ask his doctor for all the details that will be pertinent to him.