Biological control using the beneficial nematode Steinernema carpocapsae has been investigated in several areas around the United States. They do not attack people, pets, or plants. This treatment should reduce flea populations if label directions are carefully followed. The nematode treatment is probably not needed. My daughter gets bitten by fleas while I am never bothered.
Some people just smell more attractive than others to certain insects.
Individual sensitivity to the bite is another reason. To some, flea bites are extremely irritating while other people hardly notice them. This is caused by an allergic response to the flea saliva and occurs in varying degrees among people. The cocoons are deep within the carpet and treatment may not have reached them. If you did not treat your yard new fleas may be coming indoors on you or your pets.