HIV: The Most Formidable Threat to Mankind?
When we hear about HIVs (Human Immunodeficiency Virus), we are often told that it is a sexually transmitted disease that could lead to many deaths. However, do you know what makes HIV extremely dangerous? Why scientists are struggling to eradicate this disease? This article holds all the answers!
What is HIV?
HIV is a malicious virus that attacks our white blood cells (Cells that help our body fight against infections and diseases). Therefore, when we are infected with HIV, we gradually lose the amount of white blood cells in our body. Eventually, we would reach a stage where we do not have enough of these cells and lose the ability to fight against diseases. This would be the last stage of HIV infection called AIDS (Auto Immunodeficiency Virus). As a result of AIDS, we become prone to all types of disease infections. For example, did you know that AIDS patients can die from common cold?
Why is HIV threatening?
According to the US federal government’s data gathered in 2017, over 36.9 million citizens globally were infected by HIV and 940,000 citizens died from AIDS. Fortunately, with the increase in HIV awareness and effective HIV treatments, the amount of deaths decreased by half since 2004 (1.9 million). However, the number of deaths are not decreasing significantly as scientists and doctors still do not have a cure or vaccine for HIV.
What makes HIV threatening and difficult to cure?
2. HIV is a retrovirus
HIV is a special type of virus called retrovirus. Retroviruses have the ability to hide its genes inside an organism’s DNA by using an enzyme called reverse transcriptase. As a result, when we are infected by HIV, its genes becomes hidden inside our DNA. Our cells would secretly be producing HIV instead of our body cells. Therefore, HIV can proliferate easily in our body.
Most cells and microorganisms (e.g. virus) have proteins called antigens that are unique to themselves on top of their membrane. Our white blood cells determine whether a cell is harmful by detecting the shape of its antigens. However, HIV has antigens that are similar in structure to the antigens of our body cells. Therefore, our white blood cells find it difficult to identify HIV and create antibodies to fight back.
4. HIV Mutation
Unfortunately, finding a cure for HIV is extremely difficult. The enzyme ‘reverse transcriptase’ in HIV (mentioned above), frequently makes mistakes. As a result, HIV genes mutate frequently in our cells and they are more likely to become resistant to antiviral medicines. Thus, cures and medicines that scientists discover today would not last for long.
3. HIV eliminates Helper T cell
HIV has the ability to attack our white blood cells called Helper T cells. These cells are known for many important roles. They can detect infections and help other white blood cells to produce antibodies. However, if HIV eradicates Helper T cells, other white blood cells will lose the ability to fight against infections (As we cannot produce enough antibodies). Hence, HIV patients would eventually reach AIDS.
5. HIV Transfer
HIV is easily transferred from one to another through contact with bodily fluids. (e.g.) HIV can be transferred by sharing needles or having rough sex with an HIV patient (due to contact with bloodstream). Moreover, mothers can transfer HIV to their child through pregnancy. Hence, new HIV patients keep on appearing, making it more difficult to eradicate.
6. HIV - The Master of disguise
HIV patients initially experience either no symptoms or mild symptoms such as fever and headaches that could be mistaken with common cold. Hence, many people do not realise that they are infected by HIV until at a later stage. Thus, many patients receive therapy when it is too late and develop AIDS in the future.
Scientists are endeavoring to find a permanent cure for HIV, even though we still have not found a successful vaccine. However, we fortunately still have hope! We have effective HIV treatments. HIV patients who receive early treatments could live as long as an average person. As a result, if we take HIV tests regularly, we would know whether we need to take HIV treatments before it is too late. Hence, people with HIV can prevent getting AIDS in the future. Furthermore, some countries such as Japan give free HIV tests and affordable HIV treatments which effectively tackles the disease.
Moreover, did you know that with treatments, HIV patients can live longer than people with cancer?
Written by Hayato Minamiguchi, Year 12
St. Andrews International School
Sources and Further Reading:
Alberts, B., Johnson, A., Lewis, J., Raff, M., Roberts, K. and Walter, P. (2002). Helper T Cells and Lymphocyte Activation. [online] Ncbi.nlm.nih.gov. Available at: https://www.ncbi.nlm.nih.gov/books/NBK26827/.
Durani, Y. (2015). Immune System (for Parents) - KidsHealth. [online] Kidshealth.org. Available at: https://kidshealth.org/en/parents/immune.html.
HIV.gov. (2019). Global Statistics. [online] Available at: https://www.hiv.gov/hiv-basics/overview/data-and-trends/global-statistics.
Niaid.nih.gov. (2018). HIV Replication Cycle | NIH: National Institute of Allergy and Infectious Diseases. [online] Available at: https://www.niaid.nih.gov/diseases-conditions/hiv-replication-cycle.
Hivkensa.com. (2019). HIV Testing and HIV/AIDS Counseling Map in Japan | HIV検査・相談マップ. [online] Available at: https://www.hivkensa.com/language/en/.
Journal of Virology - American Society for Microbiology. (2015). Interaction between Reverse Transcriptase and Integrase Is Required for Reverse Transcription during HIV-1 Replication. [online] Available at: https://jvi.asm.org/content/89/23/12058.
Journal of Virology. (2014). Mutations in HIV-1 Reverse Transcriptase Affect the Errors Made in a Single Cycle of Viral Replication. [online] Available at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4054409/.
Rosenberg, J. (2018). People Living With HIV Have Higher Risk of First and Second Primary Cancer Incidence. [online] AJMC. Available at: https://www.ajmc.com/newsroom/people-living-with-hiv-have-higher-risk-of-first-and-second-primary-cancer-incidence.
AIDSinfo. (2018). The HIV Life Cycle Understanding HIV/AIDS. [online] Available at: https://aidsinfo.nih.gov/understanding-hiv-aids/fact-sheets/19/73/the-hiv-life-cycle.
Urmc.rochester.edu. (2019). What Are White Blood Cells? - Health Encyclopedia - University of Rochester Medical Center. [online] Available at: https://www.urmc.rochester.edu/encyclopedia/content.aspx?ContentID=35&ContentTypeID=160.