The purpose of this study is to determine whether drinking pasteurized milk (milk heated to kill harmful germs) that contains inactive particles of a flu virus called A(H5) could lead to the detection of the virus in the nose or throat. Inactive particles are not capable of causing disease. The results will help the Centers for Disease Control and Prevention (CDC) better understand how milk consumption could affect flu surveillance. Investigators also want to see if the body produces antibodies in response to this milk consumption.