HIV/AIDs

¹⁾ Fig. 1An artist depiction of HIV in the blood stream.

Human Immunodeficiency Virus, also referred to as HIV, is a viral infection spread through various bodily fluids. These vectors include blood, pre-seminal fluid, semen, breast milk, vaginal fluids, and rectal fluids. Contrary to popular belief, the HIV virus cannot spread through saliva. In order for the virus to spread, it must come into contact with mucous membranes located in varying sections of the body or damaged tissue. Through these, the HIV virus can be injected into the bloodstream. Because the virus is found in the blood, HIV can be diagnosed using blood tests. The typical person to person spread is known as HIV transmission; when HIV is transmitted from a woman to her child during pregnancy, birth or breastfeeding, it is called mother-to-child transmission.²⁾

It is believed that HIV originated in primates, likely chimpanzees, in Africa and spread to humans through a spillover event of the originally zoonotic disease. Now, the strain of HIV found in humans is solely in humans.

Individuals who have HIV become immunocompromised because HIV directly attacks the cluster of differentiation 4 cells (CD4), a type of T cell, which help the immune system fight off infection. When compromised, CD4 levels drop making an individual with HIV more likely to contract infections because their immune system is not at full strength. At the late stage of infection, a person is considered to have developed acquired immune deficiency syndrome; at this point, they will have an extremely low amount of CD4 cells and a high amount of HIV RNA present.³⁾

HIV has a seven step life cycle. The first step, known as binding, occurs when HIV connects to the receptors on CD4’s cell surface– these are known as CD4 receptors.During this process, a primary set of receptors attaches to the surface proteins of HIV which causes a conformational change to a secondary pair of receptors leading to further cell-to-cell binding.

Next, fusion occurs between the HIV envelope and the cell’s membrane; it is at this point that the HIV’s genetic information is inserted into the host cell.

The third step occurs when reverse transcriptase reads the HIV single stranded ribonucleic acid (RNA). During the first round of transcription, reverse transcriptase converts HIV RNA to single stranded deoxyribonucleic acid (DNA). Reverse transcriptase then reads it for a second round to convert the single stranded DNA into double stranded DNA. Overall, reverse transcriptase is very error prone, leading to frequent nucleotide changes. These errors contribute to HIV’s drug resistance because the DNA sequence is always changing. The multitude of changes lead to a single drug being insufficient for treating HIV.

Once double stranded HIV DNA is created, integrace carries it into the host cell’s nucleus where it is inserted into the cell’s DNA; at this point, the individual who contracted HIV has it for life, even if they are treated. After this integration, the cell begins producing the host cell proteins as well as HIV proteins. These HIV proteins are the beginning of a new HIV cell.

During step six, which is also known as assembly, the new HIV proteins are carried to the cell surface where they become immature, noninfectious HIV.

In step seven, budding occurs. Here, the new HIV breaks off of the host cell. Once separated, protease breaks up the long chains of protein in the new HIV cell turning the immature HIV to mature HIV. It is at this point where the cell is fully functional and can go infect other cells.

⁴⁾ Fig. 2 A picture depiction of HIV infecting the cell.

If left untreated, HIV can turn into Acquired Immune Deficiency Syndrome, commonly known as AIDS. For individuals who are able to treat their HIV, they are unlikely to have their HIV progress into AIDS.

There are five major stages that an individual goes through when exposed to HIV:

• Stage one is the initial infection of HIV. Infection can occur through the sharing of needles, unprotected sex, and pregnancy if the mother is affected.
• The second stage is when the infected individual begins exhibiting flu like symptoms;
• The third stage is clinical latency, or a prolonged period without symptoms. During this period, the number of T cells decline drastically while the HIV RNA copies increase.Clinical latency can last for years;
• The fourth stage is when the individual starts experiencing opportunistic infections as a result of their impaired immune system. These infections often include tuberculosis and various forms of tumors;
• During stage five, the individual begins to show late symptoms of infection, signaling the person has progressed to AIDS. A person’s life expectancy is bleak once AIDS has developed as viral RNA is reproducing rapidly.⁵⁾

Although there is no cure once an individual contracts HIV, there are antiretroviral therapies (ART) available to help slow the progression of the virus. If taken correctly, they can greatly reduce the risk of transmission to partners as well as the ability to lead a long and relatively normal life. However, if taken incorrectly or intermittently, it can lead to drug resistant strains of HIV, severely decreasing available treatment options and life expectancy. ⁶⁾

There are four main types of ART’s: nucleoside and nucleotide reverse transcriptase inhibitors, non-nucleoside reverse transcriptase inhibitors, protease inhibitors, and drugs that interfere with viral entry, such as fusion inhibitors and CCR5 antagonists. It is often recommended that a combination of these are used in order to target multiple pathways of the virus to yield the greatest outcome. These multi-drug cocktails are called Highly Active Antiretroviral Therapy or HAART.

The overall goal of HAART is to prolong the life of an HIV positive individual while also improving their immune system in order to more effectively fight off other infections. The introduction of antiretroviral therapies have been a great success in the past few decades. Such medications have led to a longer life expectancy and quality of life for affected individuals. In South Africa, there has been an overall decrease in people developing new cases of HIV as well as the number of AIDS related deaths, giving hope to future generations.⁷⁾

There are many preventative methods to decrease the chance of spreading or contracting HIV. The most effective of these include abstinence and refraining from sharing needles. Other preventative methods include using condoms and preventative medicines such as pre-exposure prophylaxis and post-exposure prophylaxis. For the aforementioned, it is extremely important they are used properly or they will not work to their full extent.⁸⁾ )

Pre-exposure prophylaxis are drugs taken daily that dramatically reduce the chance of HIV making it through your body and latching on to T cells. If used effectively, it can lower an individuals chance of contracting HIV through intercourse by 90%. Further, it can lower an individual’s chance of contracting HIV through shared needles by nearly 70%. Combining these with other methods lower the risk even more.⁹⁾

Post-exposure prophylaxis prophylaxis is a type of antiretroviral medication that must be taken within 72 hours after being potentially exposed to HIV. When in need of a post-exposure prophylaxis, every hour counts– it is much more likely to work the sooner it is taken after suspected exposure. ¹⁰⁾

Although there is no cure once an individual contracts HIV, there are antiretroviral therapies (ART) available to help slow the progression of the disease. If taken correctly, they can greatly reduce the risk of transmission to partners as well as the ability to lead a long and relatively normal life. However, if taken incorrectly or intermittently, it can lead to drug resistant strains of HIV, severely decreasing available treatment options and life expectancy. ¹¹⁾

There are four main types of ART’s: nucleoside and nucleotide reverse transcriptase inhibitors, non-nucleoside reverse transcriptase inhibitors, protease inhibitors, and drugs that interfere with viral entry, such as fusion inhibitors and CCR5 antagonists. It is often recommended that a combination of these are used in order to target multiple pathways of the virus to yield the greatest outcome. These multi-drug cocktails are called Highly Active Antiretroviral Therapy or HAART.

The overall goal of HAART is to prolong the life of an HIV positive individual while also improving their immune system in order to more effectively fight off other infections. The introduction of antiretroviral therapies have been a great success in the past few decades. Such medications have led to a longer life expectancy and quality of life for affected individuals. In South Africa, there has been an overall decrease in people developing new cases of HIV as well as the number of AIDS related deaths, giving hope to future generations.¹²⁾

There are many preventative methods to decrease the chance of spreading or contracting HIV. The most effective of these include abstinence and refraining from sharing needles. Other preventative methods include using condoms and preventative medicines such as pre-exposure prophylaxis and post-exposure prophylaxis. For the aforementioned, it is extremely important they are used properly or they will not work to their full extent.¹³⁾ )

Pre-exposure prophylaxis are drugs taken daily that dramatically reduce the chance of HIV making it through your body and latching on to T cells. If used effectively, it can lower an individuals chance of contracting HIV through intercourse by 90%. Further, it can lower an individual’s chance of contracting HIV through shared needles by nearly 70%. Combining these with other methods lower the risk even more.¹⁴⁾

Post-exposure prophylaxis prophylaxis is a type of antiretroviral medication that must be taken within 72 hours after being potentially exposed to HIV. When in need of a post-exposure prophylaxis, every hour counts– it is much more likely to work the sooner it is taken after suspected exposure. ¹⁵⁾

South Africa has the highest prevalence of HIV positive individuals in the world at nearly 7.1 million people. Because a lot of the country is still impoverished as a legacy of apartheid, those who live in South Africa are at a greater risk of contracting and being unable to treat HIV.¹⁶⁾

In South Africa, studies have shown a link between low income, high unemployment, violence, poor education, and HIV prevalence. In each of these groups, young women are the most affected by HIV than their male counterparts. This pattern is likely due to sexual and cultural norms. These norms include, but are not limited to, it being typical for a man to have many partners and few using condoms because it is viewed as being less masculine. Many men have multiple partners because they consider it to be their cultural right.¹⁷⁾

In contrast, in some African communities, women want to show they are fertile before marriage so they will attempt to become pregnant by engaging in unprotected sex, further raising their risk of contracting HIV. In some parts of rural Africa, the high rate of women with HIV is attributed to still being seen as subordinates to men as well as having limited personal resources to deal with this power struggle. In many cases, women do not have much say in when and with whom they engage in intercourse with.¹⁸⁾

Additionally, there is still a high rate of denialism regarding HIV and AIDS. From 1999 to 2008, Thabo Mbeki was at the forefront of AIDS denialism. Because he denied that HIV leads to AIDS, a major overlooking of life-saving treatment occurred causing thousands of potentially preventable deaths. It can also be argued that his unwillingness to provide effective treatment for HIV positive individuals helped it reach the point of HIV being endemic.¹⁹⁾