T.R.
Have you thought about bringing someone with you to help you out and bring your baby to the conference. Maybe an unemployed cousin or a friend taking a break from college, your cleaning help... Who takes care of your baby when you are at work? They don't need to be around during your meetings but that way you can have both participation at the conference, be seen and learn, and time with your new baby and continue the important commitment to nursing. Your helper and the baby can go exploring during the day and get to see a new place and you get to have mother baby time in the morning and at night, and maybe during other breaks in your conference day. It is a new kind of balancing act and you are still redefining career and motherhood and here is a moment in time that is saying, it won't be like other conferences I have been to because I have a 6 month old, either at home or in your hotel room, either way just her existence will effect and alter your experience at the conference. The expense is just the extra plane ticket and meals eaten out for them, your work is likely paying for the room. Chalk it up to childcare and the investment cost of keeping your career on track. The time preparing to take her on the plane and having her in a hotel for 6 days is the same or less time you will need to prepare to be away from her for that long. You can get a fridge in your hotel room for food for you and the other person to cut down on other expenses. The flu is a small factor, but if you take her into public anywhere she can be around someone who has it, just ensure no one is coughing or sneezing on her and that they wash their hands before helping you hold her. Nursing her can actually help her immune system to help keep her healthy and fight off germs and viruses. This is one of many moments that is a test of the balancing act that is career and Mommying. I was recently at a conference with a mom of a young one and all the women took turns helping and supporting her, getting her food at buffet lines, holding the baby so she could eat, playing with the baby so she could give her presentations, it actually made her more noticeable and people were in awe of her "SuperMom Powers". It depends on your career and what type of conference you are attending.
Good Luck!