This past decade has seen major advances in the treatment of HIV by the medical community. These advances took many by surprise as it was preceded by a decade of hopelessness when there was no effective therapy. When reporting on HIV/AIDS treatment it is important to have a basic understanding of how HIV weakens the immune system and how anti-HIV medications work to restore and strengthen the immune system.
The Problem: How does HIV Cause Disease?
HIV infection is peculiar in the way it leads to disease.  Unlike other viruses that cause diseases directly, HIV destroys the immune system so that other infectious agents can invade the body.
The human body is made up a variety of systems such as respiratory system for breathing, reproductive system for bearing children etc. The immune system is a collection of cells responsible for preventing and recovering from infections. It performs this function by detecting and eliminating anything that is foreign to us; therefore it has the ability to detect any infectious agents we may come across in during our daily activities. The CD4 or “T-cell” is an important infection-fighting cell of the immune system. Having an adequate number of CD4 cells is highly essential for the body to properly detect and fights infections.
Once HIV enters the body it infects CD4 cells and uses these cells to multiply (replicate), making billions of new HIV viruses each day. Release of new viruses from the CD4 cell into the blood kills the cell. These new viruses then go on to invade other CD4 cells. The CD4 cells try to prevent this invasion and initially kill a good portion of the HIV particles. However, because HIV has the ability to replicate faster than CD4-cells, the virus eventually succeeds in destroying enough CD4 cells to weaken the immune system. A weak immune system loses its ability to detect and eliminate infections, which enables other infectious agents to invade the body and cause illness or disease.
To further help you understand this concept, think about what is going on in the body of HIV infected persons as a war. The good soldiers are the CD4-cells guarding the body against invading armies and the bad soldiers are the HIV viral particles. Without treatment, the bad soldiers kill the good soldiers so that other armies (infectious agents) can invade the territory. The good soldiers fight back but the bad soldiers are recruiting and making more soldiers than the good soldiers. Eventually, the bad soldiers become such a large and powerful army that they overcome and kill a most of the good soldiers. With very few good soldiers, other armies can now invade and destroy the land.
The Solution: Preventing AIDS in HIV-Positive Persons
Now you understand the problem, the solution would be to stop the killing of the CD4 cells. To achieve this goal one would have to either give the CD4-cells the ability to replicate faster than HIV; do something to kill the HIV particles at a rate faster than they can replicate; or prevent the virus from replicating itself.
The way current anti-HIV medications work is to stop HIV from replicating itself and they do this in the following ways.
- Stopping HIV from entering CD4 cells. Anti-HIV drugs that work in this way are called Fusion inhibitors. Currently, there is only one drug available in this class and it is given by injection.
- Attack an HIV enzyme called Reverse transcriptase that HIV use to replicate. Anti-HIV drugs that work in this way are referred to as Reverse transcriptase inhibitors.
- Attack an enzyme called protease that is also involved in HIV replication. Anti-HIV drugs that work in this way are called Protease inhibitors.
Researchers are continuing to develop new anti-HIV drugs and are also trying to find ways to restore the ability of CD4 cells to defend the body against HIV.
What is HAART?
Anti- HIV drugs work best when they are taken in combination and this combination regimen is known as highly active antiretroviral therapy (HAART). Anti-HIV medications MUST be taken daily in the correct dose for them to be effective. If taken as directed HAART regimens can reduce the level of HIV in the blood to very low levels and this enables the CD4 cells to rebound to normal levels.
Although HAART is a potent treatment for HIV/AIDS, there are many problems associated with them such as:
- Serious side effects that can damage the liver, heart, kidney and bones. However, the benefits of HAART in preventing AIDS-related illness out ways most of the risk of side effects from HAART.
- HIV changes itself (mutates) quickly. In many people on anti-HIV drugs, HIV mutates into new strains that have become resistant to current anti-HIV drugs. The development of resistant strains makes these medications less potent. Failure to take anti-HIV drugs as directed encourages the development of resistant strains of the virus.
- Even among those who respond to treatment, HAART does not eradicate HIV. The virus continues to replicate albeit slowly in hidden reservoirs in the body.
How do we know these anti-HIV medications work?
In countries where HAART  has been widely available for close to a decade, the number of AIDS-related illnesses and death has decreased dramatically. HIV positive people who had AIDS have been able to return to work and other daily activity on this treatment. Also, we are now able to measure the level of HIV and CD4 in the blood (viral load) and can therefore tell if they are increasing or decreasing.
Is there a cure for HIV/AIDS?
The unique way HIV uses CD4 cells in replicating itself has made it very difficult for researchers to find a cure. Controlling the HIV epidemic would most likely be through the development of a vaccine, which would prevent infection or prevent the progression for HIV infection to AIDS. However, an effective vaccine is a least a decade away. Currently, avoiding high-risk behaviors that lead to HIV exposure is the best way to prevent HIV infection.
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