 |
|
||||||||||||||||||||||||||||||||
|
AIDS
|
|||||||||
|
 |
 What is AIDS? AIDS stands for acquired immunodeficiency syndrome. A diagnosis of AIDS is made by a physician using certain clinical or laboratory standards. What
Causes AIDS? AIDS is caused by infection with a virus called human immunodeficiency virus (HIV). This virus is passed from one person to another through blood-to-blood and sexual contact. In addition, infected pregnant women can pass HIV to their babies during pregnancy or delivery, as well as through breast feeding. People with HIV have what is called HIV infection. Most of these people will develop AIDS as a result of their HIV infection. What is HIV?
HIV (human immunodeficiency virus) is the virus that causes AIDS. This virus is passed from one person to another through blood-to-blood and sexual contact. In addition, infected pregnant women can pass HIV to their baby during pregnancy or delivery, as well as through breast-feeding. People with HIV have what is called HIV infection. Most of these people will develop AIDS as a result of their HIV infection. Where did
HIV come from?
Scientists have different theories about the origin of HIV, but none have been proven. The earliest known case of HIV was from a blood sample collected in 1959 from a man in Kinshasha, Democratic Republic of Congo. (How he became infected is not known.) Genetic analysis of this blood sample suggests that HIV-1 may have stemmed from a single virus in the late 1940s or early 1950s. The virus, perhaps, has existed in the United States since at least the mid- to late 1970s. From 1979-1981 rare types of pneumonia, cancer, and other illnesses were being reported by doctors in Los Angeles and New York among a number of gay male patients. These were conditions not usually found in people with healthy immune systems. In
1982 public health officials began to use the term "acquired immunodeficiency
syndrome", or AIDS, to describe the occurrences of opportunistic
infections, Kaposi's sarcoma, and Pneumocystis carinii pneumonia in previously
healthy men. Formal tracking (surveillance) of AIDS cases began that year
in the United States.
The
cause of AIDS is a virus that scientists isolated in 1983. The virus was
at first named HTLV-III/LAV (human T-cell lymphotropic virus-type III/lymphadenopathy-associated
virus) by an international scientific committee. This name was later changed
to HIV (human immunodeficiency virus).
|
||
|
How long does it take for HIV to cause AIDS? Since 1992, scientists have estimated that about half the people with HIV develop AIDS within ten years after becoming infected. This time varies greatly from person to person and can depend on many factors, including a person's health status and their health-related behaviors. Today there
are medical treatments that can slow down the rate at which HIV weakens
the immune system. There are other treatments that can prevent or cure some
of the illnesses associated with AIDS, though the treatments do not cure
AIDS itself. As with other diseases, early detection offers more options
for treatment and preventative health care.
How does HIV cause AIDS? HIV destroys
a certain kind of blood cell—CD4+ T cells (helper cells)—which
are crucial to the normal function of the human immune system. In fact,
loss of these cells in people with HIV is an extremely powerful predictor
of the development of AIDS. Studies of thousands of people have revealed
that most people infected with HIV carry the virus for years before enough
damage is done to the immune system for AIDS to develop. However, recently
developed sensitive tests have shown a strong connection between the amount
of HIV in the blood and the decline in CD4+ T-cell numbers and the development
of AIDS. Reducing the amount of virus in the body with anti-HIV drugs can
slow this immune destruction.
How can I tell if I'm infected with HIV? What are the symptoms?
The only way to determine for sure whether you are infected is to be tested for HIV infection. You cannot rely on symptoms to know whether or not you are infected with HIV. Many people who are infected with HIV do not have any symptoms at all for many years. The following may be warning signs of infection with HIV: • rapid weight loss • dry cough • recurring fever or profuse night sweats • profound and unexplained fatigue • swollen lymph glands in the armpits, groin, or neck • diarrhea that lasts for more than a week • white spots or unusual blemishes on the tongue, in the mouth, or in the throat • pneumonia • red, brown, pink, or purplish blotches on or under the skin or inside the mouth, nose, or eyelids • memory loss, depression, and other neurological disorders However, no one should assume they are infected if they have any of these symptoms. Each of these symptoms can be related to other illnesses. Again, the only way to determine whether you are infected is to be tested for HIV infection. What
is meant by 'Asymptomatic Period'?
It is possible to be infected with HIV without showing symptoms of illness. An individual can transmit the virus to others, even if he or she shows no symptoms. More persistent or severe symptoms may not surface for a decade or more after HIV first enters the body in adults, and within two years in children born with HIV infection. This period of 'asymptomatic' infection is variable, however. Some people may begin to have symptoms in as soon as a few months, whereas others may be symptom-free for more than 10 years. During the asymptomatic period, however, HIV is actively infecting and killing cells of the immune system. What is meant by 'Window Period'? The length of time following infection for an individual to develop detectable antibodies to HIV is known as the 'Window Period'. According to the CDC, most persons infected with HIV develop antibodies against the virus within three months after the infection. |
|
|
What
body fluids transmit HIV?
These
body fluids have been proven to spread HIV:• blood • semen • vaginal fluid • breast milk • other body fluids containing blood These are
additional body fluids that may transmit the virus that health care workers
may come into contact with:
•
fluid surrounding
the brain and the spinal cord • fluid surrounding bone joints • fluid surrounding an unborn baby How is HIV passed from one person to another? HIV transmission can occur when blood, semen (including pre-seminal fluid, or 'pre-cum'), vaginal fluid, or breast milk from an infected person enters the body of an uninfected person. HIV can enter the body through a vein (e.g., injection drug use), the anus or rectum, the vagina, the penis, the mouth, other mucus membranes (e.g., eyes or inside of the nose), or cuts and sores. Intact, healthy skin is an excellent barrier against HIV and other viruses and bacteria. These are the most common ways that HIV is transmitted from one person to another: • by having sexual intercourse (anal, vaginal, or oral sex) with an HIV-infected person • by
sharing needles or injection equipment with an injection drug user who
is infected with HIV
• from
HIV-infected women to babies before or during birth, or through breast-feeding
after birth
|
|
Can
I get HIV from kissing on the cheek?
Yes. Having
a sexually transmitted disease (STD) can increase a person's risk of becoming
infected with HIV, whether the STD causes open sores or breaks in the skin
(e.g., syphilis, herpes, chancroid) or does not cause breaks in the skin
(e.g., chlamydia, gonorrhea).HIV is not casually transmitted, so kissing on the cheek is very safe. Even if the other person has the virus, your unbroken skin is a good barrier. No one has become infected from such ordinary social contact as dry kisses, hugs, and handshakes. Can I get HIV from open-mouth kissing? Open-mouth kissing is considered a very low-risk activity for the transmission of HIV. However, prolonged open-mouth kissing could damage the mouth or lips and allow HIV to pass from an infected person to a partner and then enter the body through cuts or sores in the mouth. Can I get HIV from performing oral sex? Yes, it is possible for you to become infected with HIV through performing oral sex. There have been a few cases of HIV transmission from performing oral sex on a person infected with HIV. While no one knows exactly what the degree of risk is, evidence suggests that the risk is less than that of unprotected anal or vaginal sex. Blood, semen, pre-seminal fluid, and vaginal fluid all may contain the virus. Cells in the mucous lining of the mouth may carry HIV into the lymph nodes or the bloodstream. The risk increases if you have cuts or sores around or in your mouth or throat; if your partner ejaculates in your mouth; or if your partner has another sexually transmitted disease (STD). How effective are latex condoms in preventing HIV? Studies have shown that latex condoms are highly effective in preventing HIV transmission when used consistently and correctly. These studies looked at uninfected people considered to be at very high risk of infection because they were involved in sexual relationships with HIV-infected people. The studies found that even with repeated sexual contact, 98-100 per cent of those people who used latex condoms correctly and consistently did not become infected. Is there a connection between HIV and other sexually transmitted diseases? If the STD infection causes irritation of the skin, breaks or sores may make it easier for HIV to enter the body during sexual contact. Even when the STD causes no breaks or open sores, the infection can stimulate an immune response in the genital area that can make HIV transmission more likely. In addition, if an HIV-infected person also is infected with another STD, that person is three to five times more likely than other HIV-infected persons to transmit HIV through sexual contact. Not having (abstaining from) sexual intercourse is the most effective way to avoid STDs, including HIV. For those who choose to be sexually active, the following HIV prevention activities are highly effective • Engaging in sex that does not involve vaginal, anal, or oral sex • Having intercourse with only one uninfected partner • Using latex condoms every time you have sex |
|
Why is
injecting drugs a risk for HIV?
At the start of every intravenous injection, blood is introduced into needles and syringes. HIV can be found in the blood of a person infected with the virus. The reuse of a blood-contaminated needle or syringe by another drug injector (sometimes called 'direct syringe sharing') carries a high risk of HIV transmission because infected blood can be injected directly into the bloodstream. In addition, sharing drug equipment (or 'works') can be a risk for spreading HIV. Infected blood can be introduced into drug solutions by using blood-contaminated syringes to prepare drugs; reusing water; reusing bottle caps, spoons, or other containers ('spoons' and 'cookers') used to dissolve drugs in water and to heat drug solutions; or reusing small pieces of cotton or cigarette filters ('cottons') used to filter out particles that could block the needle. Can I get HIV from getting a tattoo or through body piercing? A risk of HIV transmission does exist if instruments contaminated with blood are either not sterilized or disinfected or are used inappropriately between clients. Instruments that are intended to penetrate the skin should be used once, then disposed of or thoroughly cleaned and sterilized. Are health care workers at risk of getting HIV on the job? The risk of health care workers getting HIV on the job is very low, especially if they carefully follow universal precautions (i.e., using protective practices and personal protective equipment to prevent HIV and other blood-borne infections). It is important to remember that casual, everyday contact with an HIV-infected person does not expose health care workers or anyone else to HIV. For health care workers on the job, the main risk of HIV transmission is through accidental injuries from needles and other sharp instruments that may be contaminated with the virus. Even this risk is small. Scientists estimate that the risk of infection from a needle jab is less than 1 per cent, a figure based on the findings of several studies of health care workers who received punctures from HIV-contaminated needles or were otherwise exposed to HIV-contaminated blood. |
|
Can I
get HIV from casual contact (shaking hands, hugging, using a toilet, drinking
from the same glass, or the sneezing and coughing of an infected person)?
No. HIV is not transmitted by day-to-day contact in the workplace, schools, or social settings. HIV is not transmitted through shaking hands, hugging, or a casual kiss. You cannot become infected from a toilet seat, a drinking fountain, a door knob, dishes, drinking glasses, food, or pets. Although contact with blood and other body substances can occur in households, transmission of HIV is rare in this setting. HIV is not an airborne or food-borne virus, and it does not live long outside the body. HIV can be found in the blood, semen, or vaginal fluid of an infected person. The three main ways HIV is transmitted are: • Through having sex (anal, vaginal, or oral) with someone infected with HIV. • Through sharing needles and syringes with someone who has HIV. • Through exposure (in the case of infants) to HIV before or during birth, or through breast feeding. Can I get
infected with HIV from mosquitoes?
No. From the start of the HIV epidemic there has been concern about HIV transmission of the virus by biting and bloodsucking insects, such as mosquitoes. However, studies have shown no evidence of HIV transmission through mosquitoes or any other insects—even in areas where there are many cases of AIDS and large populations of mosquitoes. Lack of such outbreaks, despite intense efforts to detect them, supports the conclusion that HIV is not transmitted by insects. The results of experiments and observations of insect biting behavior indicate that when an insect bites a person, it does not inject its own or a previously bitten person's or animal's blood into the next person bitten. Rather, it injects saliva, which acts as a lubricant so the insect can feed efficiently. Diseases such as yellow fever and malaria are transmitted through the saliva of specific species of mosquitoes. However, HIV lives for only a short time inside an insect and, unlike organisms that are transmitted via insect bites, HIV does not reproduce (and does not survive) in insects. Thus, even if the virus enters a mosquito or another insect, the insect does not become infected and cannot transmit HIV to the next human it bites. |
|
The combination of an ELISA / Western Blot HIV Antibody Test is the accepted
testing method for HIV infection. This combination test is looking for
the antibodies that develop to fight the HIV virus. There are two ways
to conduct this test. Either through a blood draw or through the 'Orasure'
method (a sample of oral mucus obtained with a specially treated cotton
pad that is placed between the cheek and lower gum for two minutes). Both
forms, by blood draw or orally, have the same accuracy with their results.
Other
tests that you will hear about are Viral Load tests. These tests are used
by physicians to monitor their patients who have already tested positive
for HIV antibodies. Viral Load tests are very costly and should not be
used to determine if one is HIV positive. How
do I know if I have AIDS?
You cannot tell
whether a person is infected with HIV or has developed AIDS by how they
look and appear to you.
A
person infected with HIV is diagnosed as having AIDS when they develop
an AIDS defining illness. This is the result of HIV weakening their immune
system to the point at which it has difficulty fighting off infections
that would otherwise be controlled by a healthy immune system. Because
these illness take advantage of an infected persons immune system to cause
illness, they are also know as opportunistic infections.
In many countries anti-viral drugs are available to people with HIV to help reduce the rate at which HIV weakens the immune system. There are also drugs available to prevent and treat some of the specific opportunistic infections. |
|
||||||||||
