Should I stop breastfeeding my baby if I think I have come in contact with the flu?

From the Center for Disease control http://www.cdc.gov/h1n1flu/infantfeeding.htm#d

No. Because mothers make antibodies to fight diseases they come in contact with, their milk is custom-made to fight the diseases their babies are exposed to as well. This is really important in young babies when their immune system is still developing. It is OK to take medicines to prevent the flu while you are breastfeeding. You should make sure you wash your hands often and take everyday precautions (http://www.cdc.gov/flu/protect/habits.htm). However, if you develop symptoms of the flu such as fever, cough, or sore throat, you should ask someone who is not sick to care for your baby. If you become sick, someone who is not sick can give your baby your expressed milk.