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Aids Information

What is AIDS

AIDS stands for Acquired Immune Deficiency Syndrome.

AIDS is the result of damage to the immune system. A damaged immune system is unable to protect the body against certain specific 'opportunistic' infections and tumours.

These are called opportunistic because they are caused by organisms which are normally controlled by the immune system but which `take the opportunity' to cause disease if the immune system has been damaged.

Unlike most other diseases, different people with AIDS may experience different clinical problems, depending on which specific opportunistic infections they develop. This is what a syndrome means – a collection of different signs and symptoms that are all part of the same underlying medical condition.

What is HIV

HIV stands for Human Immunodeficiency Virus. It was originally isolated in Paris in May 1983 by Luc Montagnier. It belongs to a group of viruses called retroviruses.

Viruses copy their genetic material into the genetic material of human cells. This means that infected cells stay infected for the rest of their lives.

Through mechanisms which are still not fully understood, HIV prevents the immune system from working properly. Normally, the body's immune system would fight off infection. But HIV is able to infect key cells (called CD4 cells) which coordinate the immune system's fight against infection. Many are actually destroyed by being infected; others, including CD4 cells which are not themselves infected, no longer work properly.

HIV Causes AIDS

It is widely accepted throughout the scientific community that infection with HIV is the necessary precondition for the development of AIDS.

It is of course possible for someone's immune system to be compromised in other ways, and in rare cases this can lead to the same kinds of infections seen in AIDS. When an HIV-negative person experiences immune suppression, there is usually another quite obvious cause, such as the drugs given after an organ transplantation. However, the tiny number of cases where no cause can be identified are termed idiopathic CD4+ lymphocytopenia or ICL.

Although it is clear that HIV has a central role in the development of AIDS, there remain unanswered questions about some of the specific mechanisms by which it damages the immune system. The human immune system is immensely complex and there are many ways in which it can be affected by a retrovirus such as HIV. Furthermore, it is not clear what role (if any) other factors – known as co-factors – may play in the development of immune damage.

HIV Transmission

HIV is present in the blood (including menstrual blood), semen and vaginal fluids of infected people, but can only be passed on to another person if those fluids get into that person's body. Although sophisticated laboratory techniques are able to isolate the virus from other body fluids of infected people (such as saliva), the level of virus in these fluids is far too low to be infectious.

The main ways in which HIV is transmitted are:

• Through unprotected anal or vaginal sex. HIV is unable to pass through good quality condoms, such as those bearing the British Standard kitemark.
  
• Through blood to blood contact. This mainly happens through the sharing of injecting equipment among injecting drug users. In the past, before screening was introduced, this also occurred through blood transfusions or from infected blood products such as the Factor VIII used to treat haemophilia. Very rarely, it can happen through occupational accidents amongst healthcare workers, such as needle-stick injuries. Fortunately, follow-up studies have shown that fewer than 1% of individuals who receive injuries with HIV-contaminated needles become infected.
  
• Vertically, from an HIV-positive woman to her baby during the course of pregnancy, birth or breast-feeding. The average risk of transmission during pregnancy is in the region of 10-15%, although it may be greater if the mother has a high viral load (the amount of HIV in her blood, which indicates the rate at which the virus is reproducing in the body) or has developed AIDS. Breast-feeding does carry a risk of transmission, and should be avoided in countries where good alternatives to the mother's milk are available.

HIV Detection

Usually, HIV infection is detected by an HIV antibody test. The first test to be done, usually on blood, but possibly on saliva, is an ELISA (enzyme linked immunosorbent assay). Since this test can sometimes be positive even when someone is not infected — a `false positive' — a second test called the Western Blot is done. This can confirm an ELISA.

In the US, a new Western Blot assay can provide a result within five hours. Urine-based HIV tests are also available in the US which allow people to self-test for HIV at home.

The amount of time between getting HIV infection and developing antibodies varies very widely. The vast majority of people with HIV will produce antibodies by around 45 days after infection. However, in a small proportion it may take up to six months for antibodies to develop, and in a very few people with HIV infection it may take even longer. This is one reason why a lack of HIV antibodies does not always mean freedom from infection.

It is important to bear in mind that the HIV antibody test is not an `AIDS test': there is no such thing. It is simply a test for one of the results of HIV infection. For instance, the fact that you can find antibodies to HIV in saliva does NOT mean that you can find virus there in any quantity.

There are also a number of tests which can look for the virus or parts of the virus itself (antigen testing and RNA viral load testing), or damage to the immune system, or other aspects of the body's response to the effects of the virus. These should not be confused with the HIV antibody test.

Stages of Infection

Becoming HIV antibody positive

Most people who become infected with HIV do not immediately notice that they have been infected. Some have a short illness soon after they become infected. This is called `seroconversion illness' because it coincides with the time that blood tests for HIV antibodies will become positive. The illness may take the form of a sore throat, a fever or a rash, or rarely more severe illness.

Asymptomatic HIV infection

Initially any damage caused by HIV has no outward effect. This is called asymptomatic infection, which may last for many months or years.

Sometimes people with asymptomatic HIV infection may have swollen lymph nodes, which is called PGL, persistent generalised lymphadenopathy. But this is not a sign of damage in itself.

People who have HIV and feel 100% well may nevertheless have signs of immune damage detectable by laboratory tests; for example, their CD4 count may be below normal levels. The use of viral load tests has also demonstrated that HIV is actively replicating inside the bodies of asymptomatic people from the moment of infection onwards; at no time is the virus truly latent.

Symptomatic HIV infection

Statistical studies of people with HIV have shown that the more time passes, the more likely it is that the damage will become more severe and opportunistic infections or tumours may develop. However, such statistics reflect population tendencies: individuals will have their own characteristic responses to HIV which may or may not lead to symptomatic disease.

HIV can also have direct effects upon the body. For instance, the virus can also attack immune cells in the brain. These cells are involved in feeding the brain cells. If they are damaged, the brain, or some nerves, may not work as well as usual. This is called HIV-associated dementia.

If people become ill because of these infections or tumours, they are said to have symptomatic HIV infection.

It is important to understand that apart from the so-called `wasting syndrome' and HIV-associated dementia, the symptoms of AIDS and of symptomatic HIV disease are caused by particular opportunistic infections and tumours, and not directly by HIV itself. Therefore there is a wide range of possible symptoms and it serves no particular function to answer the question: what are the symptoms of AIDS? Particular symptoms are associated with particular opportunistic infections.

An AIDS diagnosis

Before coming to a diagnosis of AIDS, doctors look at a variety of symptoms and tests. There is no single test for AIDS.

Doctors would be looking for one of the opportunistic infections or cancers in the presence of underlying immune deficiency. They might, for instance, do tests to try to seek a positive diagnosis of pneumocystis carinii pneumonia, an AIDS-defining illness.

These tests are normally only available if you've already been diagnosed as HIV antibody positive, or sometimes if you're seriously ill.

More than anything, it's a matter of accepting personal responsibility for your own health - and for those you care about. This page is here to help you make the right choices. This page offers the latest factual information about AIDS: what it is, how it is transmitted, how to avoid it.
But the real answer to AIDS control lies within each of us, in our personal decision to pursue a healthy risk free lifestyle.

Let's all be responsible for life.

Why do I need this information?

Because it's vital that everyone knows the facts about AIDS. Even if you personally have no chance of catching this deadly illness, someone you know or care about could be affected. So please, take the time to read this information. Then you'll be better informed - and able to give helpful advice to others.

What are the symptoms?

• AIDS symptoms may include:
• white spots on the tongue or mouth (thrush)
• swollen glands (lumps) on the neck or under the armpits
• severe weight loss extreme tiredness
• persistent diarrhea
• recurrent fevers and night sweats
• chronic cough
• new skin bumps, sores or discolorations

These are common symptoms in other simple illnesses, so having one or more of them doesn't necessarily mean you have AIDS. However, if you have any of these symptoms for more than two weeks, and are at risk for AIDS, you should see a doctor.

Is there a test for the AIDS virus?

Yes. A simple blood test shows when someone is infected by the AIDS virus. It does not actually diagnose the disease AIDS. Rather, it detects the presence of AIDS antibodies, substances the body forms to fight the virus. This test is very accurate after 6 months of infection.

Is there a cure?

No. At present, there is no cure and no vaccine for AIDS. However, there are effective drugs for many of the complications of AIDS, and a drug called Zidovudine (formerly AZT), which slows the disease in certain patients.

How does someone become infected?

AIDS is basically a sexually transmitted disease. The virus is present in the semen and the vaginal fluid of an infected person - and can be passed from man to man, man to woman and woman to man by anal and vaginal intercourse. Infection through oral sex has been reported in rare instances.

The virus is also present in the blood of infected people. This poses a special risk for those who inject drugs, especially for anyone who shares a needle or syringe used by an infected person.
In hospitals, standard infection control precautions are sufficient to protect patients, staff and visitors.The same risks apply with other skin¬piercing devices. It's not safe to use equipment for ear-piercing, tattooing or acupuncture unless you know it is unused or has been properly sterilized. It's also dangerous to share a razor or toothbrush with an infected person.
In most cases, AIDS is spread by sexual intercourse. You should be concerned if you have had sex since 1978 with a homosexual, a bisexual, a needle drug user, an AIDS patient or hemophiliac. Or if you've had intercourse with anyone about whose past relationships or behaviour you know little.

There is about a 25% chance that an infected mother will pass on the virus to her baby during pregnancy or at the time of birth. Medical treatment during pregnancy may reduce this chance to 8%. Drug users who have shared needles and syringes since 1978 face a special risk and should be tested for the AIDS virus. If none of these descriptions fit - relax. Your lifestyle is protecting you from AIDS.

Am I likely to get AIDS?

Your chances of being infected by the AIDS virus depend largely on your personal behaviour. High-risk behaviour creates a chain of infection from person to person.
When you have sexual relations with others, you become a link in the chain of contact. Their risk increases your risk. You need to know whether or not your partner has engaged in high-risk behaviours, or whether his or her previous partners did so.

You won't get AIDS by touching or hugging someone - even if that person carries the AIDS virus. You won't get it by sharing cups, glasses or silverware - nor from toilet seats, doorknobs, whirlpools, baths or phones. Domestic animals and pets don't harbour the virus, and there's no evidence of spread by mosquitoes or other biting insects.

Is kissing safe?

Social or "dry kissing" does not pass on the AIDS virus. Open-mouthed kissing has never been shown to spread the AIDS virus and is probably safe.

Is it safe to give or receive blood?

Blood donations are collected by skilled personnel with sterile equipment that is used only once. The same safety applies to transfusions. Since the Red Cross began rigorously checking all blood donations, the chance of acquiring the AIDS virus from blood or blood products is almost non-existent. The virus was probably not present before 1978. There is a slight chance that a blood transfusion could contain the AIDS virus. If you have ever received blood, you should discuss with your doctor whether you should be tested.

What about transplants and artificial insemination?

The government recommends that all organ and tissue donors be tested for the AIDS virus - but it's a good idea to make sure this testing was done before you receive such a donation or transplant. Those donating sperm for artificial insemination should also be checked for the virus.

How can I avoid getting AIDS?

By accepting personal responsibility for your own well-being and avoiding obvious risk.

To be absolutely safe, you should either abstain from sex or limit your sexual activity to one partner who does not engage in high¬risk behaviour - someone you know is free of infection. And never share or re-use needles or syringes. This is the only way you can be totally risk-free.

Failing these "absolutes", you can limit your risk of infection by following these rules:

• Take the time to know a person and discuss your concerns about AIDS before you become sexually involved.
• A latex condom greatly reduces the risk of catching AIDS and other sexually transmitted diseases if used correctly and regularly.
• Read the label for instructions on proper usage.
• Natural (animal skin) condoms should not be used; only latex (synthetic) condoms provide reliable protection.
• Water-based lubricants are okay, but oil-based lubricants such as Vaseline can damage condoms.
• Fewer partners, less risk. .
• Avoid anal sex - it's very dangerous.

Is it safe to travel abroad?

That depends on your destination - and your behaviour. The AIDS virus has spread to every part of the world - and in certain areas, large numbers of men and women are infected. So before you travel check with the consulate or representative of the country you plan to visit. Ask about the medical facilities in the areas in which you plan to travel, ask whether all blood transfusion are checked for the AIDS virus, and enquire whether you'll need a negative blood test for AIDS to visit that country.

Then while travelling remember:

• Do not have sex with strangers - you may get infected.
• Avoid blood transfusion in places where they are not screened for AIDS.
• Avoid needles, injections, and treatment involving surgery in areas where there may not be proper sterilization of instruments.

Sources: http://www.aidsmap.com/en/docs/42CD3282-6B1A-4A75-A8F4-B24A0E134B13.asp
Be Responsible - For Life (What You Should Know) - BC Ministry of Health.