艾滋病What_is_AIDS-英文

What is AIDS? AIDS stands for "Acquired Immune Deficiency Syndrome" and it is caused by the Human Immunodeficiency Virus (HIV). When HIV enters the human body, it will attack the CD4 cells, a kind of white blood cells, and destroy the human immune system making the infected vulnerable to attack by virus and bacteria. With the immune system destroyed, the infected will often die as a result of attack by a certain disease or diseases of different kinds. Routes of HIV transmission and preventive measures 1. Sexual contact Sexual contact includes vaginal sex, oral sex and anal sex. During unprotected intercourse, we can contract the virus through contact of wounds or cuts on our sexual organ, skin or mucous membrane with body fluids such as blood, semen and vaginal secretion which contain HIV. Safer Sex 1. Stable and monogamous relationship Understand the sex history of your partner and maintain stable and monogamous relationship with him/her. 2. Understand your sex partner Be alert when you are going to have sex with others. You may contract HIV from any sex partner. If you have doubt, you surely have the right to refuse any sexual contact. 3. Proper use of condom Proper and consistent use of condom could reduce the chance of getting HIV greatly. Proper use of condom 1. Always check expiration date or manufacturer's date before use; 2. Open the package carefully to avoid damaging the condom; 3. Use the thumb and forefinger to gently press any air out of the receptacle tip before putting on the condom; 4. Unroll the condom to cover the entire shaft of the penis; 5. Hold on the base of the condom after ejaculation and withdraw the swollen penis together with the condom from your partner's sex organ; and 6. Wrap the used condom in paper and throw it away in a waste container. * Use each condom once only; and * Never put on more than one condom at a time as rubbing will break the condoms. 2. Blood contact Transmission through blood could be a result of transfusion of blood or blood products with HIV and the sharing of contaminated needles Sharing of Needles Avoid sharing needles with others. If you have not yet got rid of substance abuse, you need to practise harm reduction by refraining from injection. If you go for injection, you have to avoid sharing needles and use each time a new syringe. If you must share needles, you have to use bleach and distilled water to clean the syringe so as to reduce the chance of getting HIV infection. Substance Abuse Stay away from drugs as the use of drugs will decrease the sense of self-protection and increase the chance of engaging in unsafe sex making oneself vulnerable to HIV infection. Handling Cuts Never handle others' cuts or blood with bare hands. It is necessary to use protector like latex gloves to avoid direct contact with the wounds or blood of other people to prevent contracting blood borne diseases such as tetanus, hepatitis B and HIV. 3. Mother-to-child transmission A mother infected with HIV has a 15% to 40% chance of passing the virus to her child during pregnancy, laboring or breast-feeding. If the infected mother and the new born baby receive early and appropriate treatment such as antiretroviral therapies during pregnancy, laboring and after birth respectively, the chance of infecting the baby can be reduced by two-third. Universal antenatal HIV testing The universal antenatal HIV testing programme has been implemented in Hong Kong since September 2001. HIV screening is now available free-of-charge to all expectant mothers attending the Maternal and Child Health Clinics of the Department of Health and antenatal clinics of the Hospital Authority. The early detection and prompt intervention, including antiretroviral therapies, can help reduce the chance of mother-to-child transmission. Can causal contacts transmit HIV? Causal contacts like shaking hands, kissing, sharing toilets and drinking fountains, eating together, going to school together or working together cannot transmit HIV. Saliva Up to now, HIV infection caused by saliva has not been reported. While the saliva of the infected can have the virus, the amount is not enough to cause infection. To cause infection, it will require at least two litres of saliva with the virus entering the body at one time. Body fluids of the infected like tears, sweat, urine and feces have a small amount of the virus which however is insufficient to cause infection. Mosquito bites Mosquito bites cannot pass on HIV as the virus cannot live inside the body of a mosquito. Mosquitoes will digest the blood they sucked and will not spit it out. Even if the mouth part of a mosquito has some infected blood, the quantity is too small to cause infection. Blood donation Donating blood to the Hong Kong Red Cross cannot get infected with HIV since all the needles are new and will only be used once. What will happen after HIV infection? Infection When HIV has entered the body of a person, he or she will become infected. About 70% of people infected with HIV will show symptoms like headaches, body aches, fevers, fatigue etc within the first 4-6 weeks. These symptoms will disappear after one to two weeks. However, symptoms do not always develop and some people can be symptom-free. Window period After entering the human body, HIV will cause the body to produce HIV antibody within 2 weeks to three months which is known as the "Window Period". For most infected persons, there will be sufficient amount of antibody for the HIV Antibody Test after a period of 3 months. If someone has done the test within the window period, then the result will not be accurate as the amount of HIV antibody is not sufficient enough to be detected. Asymptomatic incubation period HIV can live inside the human body for as long as 10 years or more. At this stage, the virus goes into a period of relative inactivity. The length of incubation period depends on the health situation, availability of treatment, psychological status etc of the infected person. There can be no symptoms at all during that period and we cannot identify someone with HIV simply by his/her appearance. AIDS and other HIV-related diseases When the immune system has been further weakened by the virus, some patients may have more serious symptoms such as: *Fever (38C or above ); *Drenching night sweats; *Severe weight loss; *Severe diarrhea for more than one month; *Persistent fatigue; *Severe headache, coughing and breathing problems; and *Lymphatic glands in more than two areas (neck, armpit and groin) swollen continuously for more than three months. The above symptoms alone cannot tell if a person has HIV or not. If case of doubt, one should go for the HIV Antibody Test. According to the definition introduced in 1993 by the USA CDC (Centres for Disease Control and Prevention), an infected person, with the amount of CD4 cells at 200 or below/ul of blood (an adult normally will have about 800-1,200 CD4 cells/ul) or having at least one kind of opportunistic infection, will have reached the stage of full-blown AIDS（晚期艾滋病）. Common Opportunistic Infections机会感染 include: *Pneumocystis Carinii Pneumonia (PCP); *Oral Thrush;鹅口疮 *Cytomegalovirus (CMV); *Mycobacterium Tuberculosis (MTB); *l Mycobacterium Avium Intracellulare (MAI); *Cryptococcus Infection; *Lymphoma; and *Kaposi's Sarcoma.