Advice plz

What should i do to help prevent my 7 week old from getting sick!? My 5 year old os currently sick with what i believe to be the flu ( will get a diagnosis on Monday) I'm so worried he's going to pass it to his little brother. Ive already sterilized my entire house I'm keeping them apart as much as i can. I have my sick son washing his hands constantly using sanitizer between and after blowing his nose. I have him coughing and sneezing in his elbow/arm no kissing baby or touching baby's things.. what else can i do?? I know i cant stop it completely I'm just trying to prevent as much as possible.