Oh, well, that doesn't sound to be an issue. I've had a low grade fever lately without explanation. Reason I asked is that I read somewhere that you can get "serum sickness" just from using too much injectable formula. I've been using a lot lately due to low concentration in one of the products I have and thought that might be the issue since I don't have any other symptoms and I haven't been around anyone else who is sick and haven't done anything else to get sick. Didn't know if that could be the issue.