HIV As A Major Global Problem
Sexually transmitted diseases occur due to several various bacteria, viruses, protists, and fungi. They are spread from one individual to the other via sexual activity including vaginal, oral, or anal sex as they are usually transmitted over body fluids from the genitourinary tract, or blood in the case of HIV. Examples of sexually transmitted diseases include gonorrhea, chlamydia, HPV, syphilis, and HIV. HIV, or human immunodeficiency virus, is a virus that mainly attacks the immune system, making the risk and impacts of other illnesses greater. If left untreated, the HIV virus may progress to an advanced disease stage known as AIDS which is characterized by multiple, potentially fatal, illnesses including rare cancers, pneumonia, tuberculosis, chronic diarrhea, and more. According to the most recent survey, which was published by Public Health England in 2018, the prevalence of HIV in the UK was estimated at 101,600.
The World Health Organisation states that since the HIV epidemic has begun, over 75 million people have been infected with the virus, resulting in 32 million fatalities (WHO, 2018). The African region is most severely affected with nearly 1 in 25 adults suffering from HIV. Some populations are more at risk and vulnerable in comparison to the general population. The World Health Organisation guidelines define the most at-risk populations as “men who have sex with men, transgender people, people who inject drugs and sex workers”. In addition, young women and girls in southern and eastern Africa and indigenous people in some communities are also at great risk, given their circumstances (Hemelaar and Gouws, 2013). Many of the vulnerable populations disproportionately suffer from the infection in most epidemic contexts. These vulnerable populations are where there is a ‘concentrated epidemic’ where HIV has spread rapidly due to the social and demographic characteristics of the region. In comparison, the epidemic is not well established in the general population and prevalence is low in the general population.
There are two distinct types of HIV: HIV-1 (which is the most common one) and HIV-2 (less common in comparison and relatively less infectious). The strain Group M is the most common of the 4 classified groups of the HIV-1 virus and is responsible for the greater part of the global HIV epidemic. According to (Campbell-Yesufu, Omobolaji T., and Rajesh T. Gandhi 2011), the rarer HIV-2 virus is concentrated in West Africa and is relatively less infectious and results in lower fatality due to progressing to an advanced stage more slowly, although sufferers of HIV-2 will eventually develop AIDs and die from the disease. Although the two types of viruses are genetically different, the pathophysiology of both is the same. The virus damages and destroys a specific type of white blood cell which is found in the immune system – the CD4 cell. These cells play a significant role in protecting the body from infection. The HIV virus then multiplies and spreads throughout the body by using the machinery of the CD4 cell. The process in which HIV spreads is carried out in 7 stages called the HIV life cycle. These 7 stages consist of binding, fusion, reverse transcription, integration, replication, assembly, and budding (figure 1). In the figure, the different stages are also linked to different antiretroviral drugs which stop HIV in different ways depending on the stage of the life cycle. In the first stage, which is the attachment or binding stage, the virus binds to the receptors of the CD4 cell and the drugs which prevent this from happening are CCRS antagonists and post-attachment inhibitors. The next stage is fusion, where HIV enters the CD4 cell by fusing with the CD4 cell membrane. Fusion inhibitor drugs can prevent this. In the third stage, the HIV virus can enter the nucleus of the CD4 cell and combine with its DNA using the reverse transcription. The drugs useful at this stage are nucleoside reverse transcriptase inhibitors and non-nucleotide reverse transcriptase inhibitors. The fourth stage of the cycle is integration, during which the HIV enzyme integrase is released in the nucleus and is used to integrate the HIV DNA with the CD4 cell DNA. This process can be inhibited using integrase inhibitors. The final two stages are assembly and budding where new viral RNA and HIV proteins move to the cell surface and form new, immature HIV which is then released from the CD4 cell and secretes protease to create mature HIV.
In the absence of proper treatment, the HIV infection advances in stages, progressively worsening over time. There are three stages of the infection, the first one being Acute HIV Infection. This is the earliest stage of the infection and normally takes 2-4 weeks to develop after an individual has been infected by HIV. The symptoms during this stage are common, flu-like symptoms like fever, headache, and rash. During this stage, the virus multiplies and spreads at a high rate, throughout the body. Also, during this stage, the risk of HIV transmission is great as the level of HIV in the blood is high. The Centers for Disease Control and Prevention state that antiretroviral therapy (ART) started at this stage would result in significant health benefits for the patient (Besser et, al, 2009). The second stage of the HIV infection is Chronic HIV Infection (also known as clinical latency), during which the HIV cells carry on multiplying at significantly lower levels. Usually, no HIV-related symptoms are present in a patient during this stage and this stage generally advances to AIDS in roughly 10 years. Transmission of the virus is still possible in this stage, however, people who are undergoing ART have effectively no risk of transmitting HIV through sexual activity. Patients undergoing ART may remain in the Chronic HIV infection stage for several decades. The final stage of HIV infection is the most severe one and is known as AIDs. By this stage, the virus has critically damaged the immune system and it is unable to fight off opportunistic infections which are usually fatal to the weakened immune system. Some of these infections include candidiasis, invasive cervical cancer, herpes simplex, lymphoma, tuberculosis, and more (NHS, 2019). According to Stanford Healthcare (2010), AIDs is diagnosed in a patient when the CD4 count drops below 200 cells/ mm3. Once this stage is reached, the risk of transmitting the HIV virus becomes high again. Patients diagnosed with AIDs typically survive around 3 years without treatment.
Although there is no cure for HIV, there are several highly effective treatments that enable sufferers to lead a long and healthy life. One example of a preventative treatment that may prevent infection soon after being exposed is the post-exposure prophylaxis medication, also known as PEP. This must be taken within 72 hours of contact with the virus for it to be effective. All other treatments are for patients who have already been diagnosed with the virus. There are many rapid diagnostic tests that can provide results within hours which greatly facilitates diagnosis and improves treatment and care. A common treatment for HIV is antiretroviral medication/ antiretroviral therapy (ART) and is used in the various stages of the HIV life cycle as shown above, which prevents the virus from replicating inside the body and allowing the immune system to repair itself and stop even more damage. The HIV virus can quickly adapt and become resistant so a combination of drugs may be used. There are different classes of anti-HIV drugs used in ART and it is recommended to combine three drugs from two different classes to prevent making a drug-resistant strain of HIV. Each class blocks the virus in its own way, these classes include non-nucleoside reverse transcriptase inhibitors, nucleoside reverse transcriptase inhibitors, protease inhibitors, entry/fusion inhibitors, and integrase inhibitors. Many people who suffer from HIV also try alternative or herbal options for treatment, for example, chiropractic or acupuncture therapy. Although there is no evidence that confirms these methods to be effective in curing the virus, they may relieve symptoms and improve a patient’s quality of life.
Overall, HIV continues to be a major global health issue, affecting some parts of the world significantly more than others, having taken over 32 million lives up until this point. However, as access to effective HIV prevention and treatment becomes greater, the infection is now more manageable, allowing patients of the infection to lead long lives. Although there is no cure for HIV yet, more research is being conducted towards new preventative measures and potential cures such as broadly neutralizing antibody treatment and even HIV vaccines. Alongside this, there is continued research to develop new drugs with unique mechanisms of action for antiretroviral therapy which would be more effective against HIV strains that have developed resistance to other types of drugs. According to the World Health Organisation, between 2000 and 2018, new HIV infections fell by 37% and HIV-related deaths fell by 45%, with 13.6 million lives saved due to ART which shows that this treatment method is relatively successful. Despite this progress, major challenges must be overcome to make the global impact sustainable and to end the AIDS epidemic because HIV remains one of the leading causes of death worldwide.