Leukemia may begin with such an innocent phase as the flu. This dangerous illness is often confused with the ordinary flu, which prevents people from acting on time. One should try to memorize chronic and acute forms of the disease exist. Being susceptible to contagion is the first sign of the risky disease which should not be ignored, especially when followed by other symptoms. The patient starts coughing, trembling, feeling cold, sweating at night, and having high body temperatures.