Symptoms include headache, anemia, joint pains and swollen tissues. Advanced signs include neurological and endocrine disorders. As the parasites invade the central nervous system (CNS), mental deterioration begins, leading to coma and death. T.b. rhodesiense infection is usually acute, causing severe symptoms and death within a few days or weeks. T.b. gambiense infections tend to progress more slowly over several years and are less severe.