Acquired immunodeficiency syndrome (AIDS), which is caused by HIV viruses, is a fatal infection in the 21st centuries. AIDS originally appeared in South Africa in 1920s. Such kind of infection quickly spread around the world after local chimpanzees had communicated the disease to humans. Consequently, it is estimated that 77.3 million people are diagnosed with HIV, almost half whom have passed away due to AIDS-related diseases. The disease seriously poses a threat to countries of Swaziland, Botswana, and Lesotho. However, it doesn’t mean that only undeveloped countries are suffering from the infection. The developed country such as America has more than 300,000 people diagnosed with AIDS per year. Therefore, it is important to know how AIDS develops and what forms of symptoms would appear in our bodies in fear of missing seeking medical advice in the best of time. There are three stages of HIV infection: acute infection, clinical latency, and acquired immunodeficiency syndrome.

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      Acute infection, the initial stage of AIDS, will generate a series of symptoms to illness. The reason is that a HIV virus multiplies at a high speed and constantly destroys Cluster of Differentiation 4 receptors(CD4), a kind of immune cells, during the time. Attacked immune systems thus can’t beat against usual diseases ,which causes several symptoms such as rash, fever, chills, headache, fatigue, sore throat, and night sweats similar to getting a cold. Normally these conditions will disappear until two to four weeks even without seeing doctors. Nevertheless, it does not reflect that HIV virus is wiped out by immune system as a normal one. Instead, the next stage, clinical latency, has gradually been around the corner in an unaware way.

 

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     Unlike acute infection, clinical latency as a second stage is analogous to chronic disease. That is to say, patients who keep taking medicine can prevent themselves from deteriorating in this stage for 20 years even more. What’s more, well-controlled patients noticeably have no symptom because HIV viruses multiply at a lower speed than the other stages. Probability of infection to others will decrease as well. Even though sicknesses in the period seem to be well and sound, taking prescribed medications is important for them. Thus, no obvious disease can risk their lives.

 

 

 

 

 

 

 

 

     If the condition loses control, acquired immunodeficiency syndrome (AIDS) is the final and most severe stage of HIV infection. The indication of the stage is determined by CD4 levels. The patient in the final stage has less than 200 cells/mm3 of CD4. The immune systems thus are not able to fight against opportunistic infections, a type of situation that virus occurs in the weakened immune system. In addition, there are several common symptoms like persistent high fevers 37.8°C, severe chills and night sweats, persistent headaches, memory problems, and fatigue. Once above-mentioned symptoms happen, it is rare to see people who are diagnostic with AIDS survive.

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     To sum up, the earlier two stages of AIDS, acute infection and clinical latency, are easily ignored because AIDS and normal cold of symptoms are too similar to be distinguish. Once missing the opportunity to seek for medical advice, AIDS, the final stage of the infection, would claim people’s lives within ten years. Surely AIDS preventions are more important than any forms of treatments. We should avoid unprotected sex and nonmedical purpose of blood contact. Unfortunately, if you were the one who was probably infected by HIV at a high risk, go to see doctors immediately no matter how subtle the illness is. In this way, we can minimize the injury of AIDS in a large rank.