The cold and the flu are both common illnesses. You can tell the difference by how fast to comes on. Flu also tends to have a higher fever in adults. Both can cause sore throat, cough, stuffy head and will make you feel miserable. Both are caused by viruses, and have no cure - get better when your body makes you better. As flu can be more serious, doctors may prescribe an antiviral medication. Unlike the common cold, it is possible to prevent some flu or to reduce its severity by getting an immunization for current flu strains.