There are many medical problems in the modern society. One of the most alarming medical problems in the world is a【21】______disease named HIV virus. This kind of virus is first【22】______twenty years ago. It weakens the body and develops fully blown AIDS. AIDS is not obvious in the early stage. Sometimes symptoms occur within a few weeks after 【23】______ . They are often flu-like, such as 【24】______ , fever, headache, diarrhea and night sweats. The three main 【25】______ routes of HTV are sexual contact, exposure to infected body fluids or tissues and from mother to 【26】______ or child during perinatal period. This kind of virus can always 【27】______ some families apart. People's first 【28】______ is a denial about their loved one's condition. HIV positive people are those who have tested positive for the virus. 【29】______ they are related to conditions that are far less serious than HIV, they can only be treated when potential patients are 【30】______ of the risk of infection. They choose to deal with the risk instead of avoiding of it. 【31】______ tests are the best way to monitor HIV because they can slow the progress of the virus【32】________time. But we have to admit that it is no longer associated 【33】______ death immediately, but drugs are not 【34】______ . Doctors 【35】______ HIV positive people to have regular tests to monitor the progress of the disease. By now there is still not successful vaccination against HIV, so much effort has been 【36】______ mainly on educating the public about 【37】______ HIV is passed on . In addition, more emphasis is contributed to introduce to the citizens about personal measures that 【38】______ the risk of infection. 'We are concerned about these individuals, because we know that early treatment can help 【39】______ their life and ensure that they do not 【40】______ others, including their newborn children. ' Dr Donald Gelhorn (president of the College of Family Physicians of Canada) says. 【21】