Aids (acquired immunodeficiency syndrome)

Introduction AIDS (acquired immunodeficiency syndrome) results from the late stage of infection with HIV (human immunodeficiency virus). In adults, the onset of AIDS can take up to ten or more years, and new drug therapies can delay the progression of the disease into AIDS even longer. Thus, a person infected with HIV may look and feel healthy for many years, but he or she can still transmit the virus to someone else, which is why it is very important for individuals to get tested.


Today, the global AIDS crisis affects 43 million people, but in the West people have become complacent to the dangers. The AIDS epidemic has so far left 50 million people infect with HIV worldwide, 16 million have already died. That leaves 34 million people who are living with the infection. Africa has been the worst hit- 5.500 people die from AIDS-related illnesses there every day. There are new fears, that Asia may eclipse Africa in severity of infection levels. However, the steepest rise in infections in the world during 1998 was in the former Soviet Union and Eastern Europe. There are 1, 4 million children with Aids worldwide.
Campaigners say people who are too young to remember the massive AIDS-campaigns of the 1980s are becoming complacent about the risks of the disease. People are still ignorant about the risks of becoming infected with HIV, one in ten people wrongly believe there is a cure for AIDS and a further one in ten are not sure. Only a third of people aged 15-24 say that knowledge of HIV has made them change their lifestyle in some way - an 11% drop on the year before.
There is still no cure, the new and effective drugs have been responsible for fewer people developing full-blown AIDS and increasing the numbers of HIV positive cases.


About the Virus
HIV is present in infectious quantities in blood and blood products, semen and possibly pre-cum, vaginal and cervical secretions and also breast milk. During invasive surgical procedures healthcare workers may also come into contact with the following bodily fluids, which contain significant amount of HIV: Amniotic fluid, cerebrospinal fluid and synovial fluid around bone joints.
HIV us also present in negligible quantities in tears and blister fluid, but is not present in urine, vomit and sweat.
Generally the fragile nature of the virus prevents it from surviving for a substantial amount of time in the open air. The only studies on the survival of HIV outside the body have been conducted in the laboratory under controlled scientific conditions. These studies have found HIV is not affected by extreme cold, but it is destroyed by temperatures of 60 degrees centigrade and above.
Scientific studies have found that HIV can sometimes survive in dried blood at room temperature for up to six days. It is extremely difficult to assess exactly the length of survival of HIV outside the body in a non-laboratory setting.
HIV can't create itself under any circumstances. The virus has to be present in a person's body and then passed on to someone else. HIV doesn't develop in a person's body of its own accord like for example cancer.
HIV is a transmissible infection, which is passed from one person to another. The only way that a person can become infected with HIV is if bodily fluids of an infected person get into the body of an uninfected person. The main ways in which HIV transmissions takes place are through unprotected vaginal or anal sexual intercourse, e.g. sex without a condom. Through blood to blood contract, usually infection in this way is the result of sharing needles with an infected person. Finally infection may take place from an infected mother to her child either in the womb at birth, or through breast-feeding.
Although it is possible to become infected through oral sex, the risk of becoming infected in this way is much lower than the risk of infection through unprotected sexual intercourse with a man or a woman. When giving oral sex to a man, a person could become infected with HIV if infected semen got into any cuts, sores or receding gums a person might have in their mouth. Giving oral sex to a woman is also considered relatively low risky. Transmission could take place if infected sexual fluids from a woman got into the mouth of her partner, the likeliness of infection occurring might be increased if there is menstrual blood involved or the woman is infected with another disease.
While research suggests that high concentrations of HIV can sometimes be detected in pre-cum, it's difficult to judge whether HIV is present insufficient quantities for infection to occur. To guard against the possibility of an infection with HIV or any other sexual diseases it is best to practice safer sex, with a condom.
Deep kissing is a very low risk activity in terms of HIV transmission. HIV is only present in saliva in very minute amounts, insufficient to cause infection with HIV alone. There has been only one documented case of someone becoming infected with HIV through kissing, a result of exposure to infected blood during intensive kissing.

What happens when someone has HIV?
Most people who become infected with HIV don't notice that they have been infected. A few weeks after infection, the body's immune system reacts to the virus by producing antibodies. Some people with HIV have a short "seroconversation" illness at the time these antibodies are created. The likely symptoms are the normal response to many other infections, and may include a sore throat, a fever or a rash.
Someone living with HIV will have their CD4 count and viral load regularly monitored by means of simple blood tests. The results of these tests vary in response to infections, stress, exercise and the time of day, but it's of primary importance in indicating how their health is holding up under the assault of HIV. When someone has lived with HIV for a long time and their immune system has been severely damaged, there is a risk of opportunistic infections. Increasingly, it is possible to prevent or treat opportunistic infections, which may arise in someone living with HIV using drugs. For example, Pneumocistis carinii pneumonia (PCP) was a frequent cause of death in people with AIDS or late stage infection in the early years of the epidemic. Doctors are now able to prevent PCP with drugs, or to treat it quickly if it occurs. Death from PCP is now rare among people with HIV in industrialised countries.
The most effective way to attack HIV is with a combination of anti-HIV drugs. Combination therapy is a huge advance in the treatment of HIV, and many people have done very well on it. Combination therapy is not a cure and, because of complex rules governing how drugs need to be taken, various drug regimens can be difficult to take or adhere to.
But combination therapy has greatly reduced the number of people dying from HIV. As a consequence of combination therapy, today in Europe five times fewer people are dying of HIV infection than in 1995.



The search for an HIV vaccine
Soon after the identification of the virus in 1983, some health officials were predicting that a vaccine would be developed within a few years. Although it proved to be much more difficult, scientists are confident that an HIV vaccine will be discovered.
In 1987 the first human trial of a candidate HIV vaccine was conducted in the US. About 30 experimental vaccines have since been tested in about 60 trials.
So far, most of the trials have been staged in industrialised countries, but now trials are increasingly being done in developing countries also. During the 90s, several vaccine initiatives were launched in developing countries, including Africa.
A vaccine will not be a panacea, nor will it be an alternative to prevention. Because an eventual vaccine is unlikely to be 100% effective, it will have to be used alongside wide-ranging and effective prevention programmes. In fact, once a vaccine is developed, awareness-raising and prevention efforts will need to be redoubled in order to counter the risk of complacency. An HIV vaccine must benefit all humanity. Once discovered, the vaccine will have to be made available to everyone with minimum delay, in sufficient quantities and at affordable prices. Early planning is needed to ensure that this is achieved.
The peculiarities of the virus make the development of a vaccine an arduous and expensive process. Still lacking, for instance, is the clear scientific understanding required to guide the pharmaceutical development of specific candidate vaccines.
HIV/AIDS differs profoundly from most other infectious diseases. In the case of the latter, the body develops and immune response to an infection in order to protect itself and help it recover from disease. A successful vaccine against such diseases therefore stimulates effective immune responses, leaving them incapable of controlling infection or preventing disease.
Most existing vaccines are based on an entire microorganism (virus or bacterium) that has been killed or rendered harmless. In the case of HIV, however, those classical vaccine approaches are not considered sufficiently safe. Experimental HIV vaccines therefore are based on parts of the virus (to ensure that vaccination does not result in HIV infection). This makes the development of a vaccine even more challenging.
Ten subtypes of the HI-Virus have already been identified. Scientists do not yet know whether a vaccine will have to be prepared for each subtype or whether a more broadly protective vaccine will be possible. That, coupled with the fact that the subtypes in developing countries differ from those prevalent in the industrialised world, makes it essential that experimental vaccines be developed simultaneously in the North and South.
Scientists know that the development of a vaccine is possible (because animals can be protected against HIV infection), but they remain uncertain as to whether that success can be extrapolated to humans. For that reason, the search for an HIV vaccine has to include human trials, which are costly and time-consuming.