The primary warning sign of measles is the pain in the body. Human organism are mechanisms functioning with the certain level of ‘fuel.’ We call it energy. The energy is needed everywhere, even when it comes to mental health. Such functionality as the digestion also requires some fuel. The organism wastes more energy when it fights certain infections. As a result, the person feels weaker than he or she usually does. The body reacts to measles in particular way. The general discomfort is supported by the weakness and pains in various parts of the body.