by Johnathan Yong Yung Chien (CM118)
The human immunodeficiency virus, or more commonly known as HIV, is the culprit behind what has been infamously known as the acquired immune deficiency syndrome, or AIDS. AIDS has plagued civilization for decades on end. Ever since the disease dawned, an estimated number of 36 million people had died from the disease, with 70 million more and counting of the global population being sufferers of the virus. At present, no real cure has been discovered for the eradication of the disease. However, with the continuous discoveries and breakthroughs made in the field of medicine, the human race is closer than ever to counter and eradicate HIV once and for all.
In the understanding of the modern-day society, AIDS is a sexually transmitted disease (STD). Mass media merely highlights that HIV spreads through the conduction of unprotected sexual acts via the exchange of bodily fluids such as pre-ejaculates, semen, and vaginal discharges. In reality, HIV can also be spread through other mediums, such as blood. This is where a healthy individual comes into contact with HIV-positive blood through means such as open wounds, contaminated needles, blood transfusions, etc. Besides that, the virus can be passed on from an already infected mother to her new-born child. There is also a chance for a baby to contract HIV from being fed breastmilk. Contrary to popular belief, HIV does not spread through mediums of air, water, and casual contact.
In the scientific field of microbiology, HIV is more specifically identified as a retrovirus. The way in which HIV infects its host is through the integration of its own DNA with the host cell’s genome. The host’s genomic structure, therefore, will be changed, and subsequently, its functions compromised, effectively rendering itself a factory for synthesizing mass copies of its lodger. Once the host cell dies via apoptosis, the newly synthesized viruses will emerge out of the host and infect other healthy cells. This effectively creates a cascade of continuous attacks on healthy cells.
Why is AIDS considered dangerous in the understanding of the medical field? While not directly causing any deaths itself, it does all the dirty work until there is an opportunistic infection that can finish the job. HIV predominantly sets a type of white blood cell as its target, which is the CD4+ T cells. CD4+ T cells, or more commonly known as the T helper cells, play an important role in the mounting of a regulated adaptive immune response against pathogens. These cells will mount an immune response at first contact with the virus, causing early symptoms such as fever, headache, tiredness, etc. However, for a time period ranging from a few months to several years, the virus will go into a ‘latency stage’. During this period, the individual may look and feel completely healthy, yet the virus will continue to replicate at low levels and destroy T helper cells of which the immune response against the virus is already impaired. The current stage of the HIV infection can last for years on end before a person eventually progresses to AIDS, during which the coexisting virus had already effectively caused the dysfunction of the T helper cells. With the T helper cells exhausted and greatly lessened in numbers, the body essentially will be unable to defend itself against even the most commonplace of pathogens, such as the fungus Pneumocystis jiroveci. This fungus is found naturally in the environment and normally doesn’t cause any life-threating illnesses. However, for individuals suffering from AIDS, exposure to said fungus can cause fungus-induced pneumonia, which can eventually lead to mortality.
At the present stage, there is no identifiable cure for HIV/AIDS. However, further research carried out in recent years suggest effective pathways to combat the spread and progression of HIV in already infected individuals. Antiretroviral (ARV) therapy is one such pathway. It works in such a way that it targets and blocks the different phases in a virus’ life cycle, effectively impeding the virus from replicating and synthesizing new copies of itself within the host cell. While antiretrovirals do not work by killing the viruses, the viral load in the body can decline to a level where it can be considered undetectable when treatment is carried on long enough.
Aside from that, antiretrovirals also help individuals who are not yet infected with HIV to prevent against contracting it. The approach taken by the antiretrovirals is known as pre-exposure prophylaxis (PrEP). PrEP treatment is conducted when people pose high risks of contracting HIV, such as having a sexually active lifestyle or performing unprotected sex. It works effectively among these individuals by blocking HIV from establishing and spreading itself in the healthy individual’s body. The drugs administered for ARV treatment should be taken consistently in both cases. However, there might be a risk of relapse or development of drug resistance should treatment be halted.
A potential cure for HIV might be in the works, after all. There’s the one successful case of total HIV eradication in a patient in the year of 2008. Timothy Brown, or more famously known as the ‘Berlin Patient’, is the one and only person who is completely cured of HIV. After having been previously diagnosed with leukaemia, he had undergone chemotherapy and a bone marrow transplant. The donor of the bone marrow transplant was apparently naturally resistant to HIV. Initially, the patient did not recover fully after the transplant; he had suffered from delirium, blindness, and nearly whole body paralysis. Eventually, he learned how to walk again and fully recovered after 6 years. The news shed new hope unto discovering the potential cure of HIV, for the successful case had provided important and valuable information towards finding a potential panacea. As what David Mixner, a human rights activist, once said: “Embrace and celebrate the progress while not letting up the pressure until there is a cure.”
The research on HIV can unlock ever so many new doors in the field of science, but many more challenges may arise should such a cure emerge. Are these treatments readily available for individuals from all walks of life? What about the commercialization and patenting of such drugs? Should future governments place down huge funds for the welfare of its citizens? The possibilities are endless. However, I believe that it is the responsibility of the government, scientists and all healthcare personnel to make sure that the cure can reach to whomever most needs it as receiving these medications requires access to a well-functioning healthcare system. With continued research and progress, a world without HIV is no longer unconceivable.
We are much closer than ever.