is my family safe living with a person who suffers a baterial infectial in her stomach as a result of gall bladder surgery

My mother was admiited to the hospital on April 13,2008 due to: Extremely high fever, vomiting, dillusional. The doctors at the hospital diagnosed my mom with: Phneumonia, and an Enlarge gallstone in my mother's Gallbladder.She had to have surgery to remove the enlarge gallstone from her gallbladder. She was released from the hospital on April 22,08. And I as her daughter feels they dishcharged my mom way to early before she was healed a few days later the hospital called my mom and told her that she picked up a bacterial infection of the gastointestinal and the medicine my mom is prescribed to take due to surgery on her stomach is causing her to carry two contagious viruses,but if my mom dont take the medicine that was prescribed for her wound she'll be in alot of pain i asked my mother why doesn't the doctor prescibe you another brand of medicine she said that they said they have to do some research of what my mom can take diffrently then what she is taking now do to her Diabetes. My Question is: Are my sister and her 11 month baby at serious risk of catching these contagious viruse and if Yes what are the risk because they are living in the same house as my mother?

[Jaybay]

I don't think anyone here can answer that question without knowing what the specific virus or bacteria is.  Your best bet would be to talk to your mom's doctor yourself and ask if family members need to take any special precautions regarding your mom's illness.