Epidemiology, Outbreaks

The Difference Between HIV and AIDS: Latest Research Progress for Vaccine, Cure, and Treatment

Author Chandana Balasubramanian , 21-12-2021

The search for an effective AIDS vaccine may have turned a corner. The U.S. National Institutes of Health (NIH) recently stated that experimental mRNA vaccines showed promise in mice and non-human primate studies. Scientists from the NIH published these results in the journal Nature Medicine [1]. In the NIH press release, Dr. Anthony Fauci, Director of the NIAID and a co-author of the paper stated, “This experimental mRNA vaccine combines several features that may overcome shortcomings of other experimental HIV vaccines and thus represents a promising approach.”

 

The news of a potential vaccine is highly welcome. Hopefully, the vaccine can help eradicate AIDS-related mortality in the future. Over four decades, the world made enormous strides in immunotherapy and raising awareness about the spread of HIV infections. These measures have helped lower infection rates considerably. Globally, new HIV infection rates are four times lower than in the late nineties, when infections were at an all-time high. A whopping three million global deaths from AIDS were reported in 2000 and this number was reduced to about 700,000 by 2019.

 

 

Image: Chart depicting worldwide death rate due to AIDS from 1990 to 2020. Copyright © GIDEON Informatics, Inc.

 

How AIDS Started and Spread Worldwide

 

The HIV virus is known to have originated from chimpanzees in Central Africa. The CDC states that zoonotic transfer of HIV to humans may have occurred as early as the 1800s when hunters came in contact with infected chimpanzee blood. Other accounts suggest that the HIV virus crossed over from chimps to humans in the 1920s. Using genetic dating methods, researchers David Ho et al. from the Aaron Diamond AIDS Research Center in New York discovered that HIV may have originated in the 1940s or 1950s [9].

The first official reporting of AIDS in the United States was in June 1981 in Los Angeles. The cause of death was severe pneumonia, but the case was retroactively declared an AIDS-related opportunistic infection.

Difference between Them: Related But Not the Same

 

Though some people may use the terms AIDS and HIV interchangeably, they are not the same. HIV stands for Human Immunodeficiency Virus. It is the name of the virus that attacks and weakens the immune system. Without effective treatment, HIV-infected individuals are often unable to ward off other diseases. AIDS, Acquired Immunodeficiency Syndrome, is the most severe stage of HIV [2] [3].

So, HIV does not always turn into AIDS. However, all patients with AIDS have HIV.

It can take eight to ten years for an HIV infection (without treatment) to turn into AIDS [4]. HIV can be sexually transmitted, spread by contact with infected blood, or from a mother to her child during pregnancy or breastfeeding.

Symptoms of HIV and AIDS

 

According to the NIH, there are three stages of an HIV infection [5].

They are:

  • Stage 1, Acute HIV
  • Stage 2, Chronic HIV, and
  • Stage 3, AIDS (Acquired Immunodeficiency Syndrome)

 

Stage 1 HIV: Acute HIV

The acute HIV phase develops within two to four weeks after the initial infection. HIV replicates rapidly, and the risk of transmission is high. It destroys the body’s CD4 T-lymphocytes, a type of white blood cell crucial to help fight infections. At this stage, some may experience flu-like symptoms. These include fever, rash, headache, joint pain, muscle pain, sore throat, and more.

Stage 2 HIV: Chronic HIV

During Stage 2 of HIV, HIV cells multiply but at low levels. Because of this, some people with chronic HIV infections may not experience symptoms. If left untreated at this stage, it can progress into the next stage over a decade or so.

Stage 3 HIV: AIDS or Symptomatic HIV

Stage 3 of HIV is considered AIDS. By this time, an infected individual’s immune system is fragile and vulnerable to, what is known as, opportunistic infections.

According to the CDC, “Opportunistic infections (OIs) are illnesses that occur more frequently and are more severe in people with HIV.” These include bacterial infections like Candidiasis, cervical cancer, fungal infections like Coccidioidomycosis, Herpes Simplex Virus, lymphoma, tuberculosis, pneumonia, and many more [2].

The virus is most transmissible during the very early stages of the infection. This is one of the reasons for the AIDS epidemic in the 1990s and early 2000s.

 

There is a Treatment for AIDS; It’s Still High-Risk For Patients

 

When available, an effective AIDS vaccine will be another significant milestone in the battle against AIDS and HIV infections. After all, it was only in 2011 that Timothy Brown, an HIV-infected individual, was declared the first patient “cured” of HIV. Timothy received stem-cell transplants.

A few years later, in 2019, Adam Castillejo became the second patient cured of his HIV infection. Known as the ‘London Patient,’ Adam was treated with a bone-marrow transplant for his stage 4 lymphoma. Fortunately for him, the donor stem cells contained a mutation resistant to the HIV virus, strengthening his immune system. As the New York Times reported, Mr. Castillejo received the treatment as a stroke of luck. He happened to match with several bone-marrow donors, including one who had a mutation called the Delta-32. The Delta-32 offered resistance against HIV [6]. 

While the treatment was successful in these two patients, the procedure is still high-risk. The search for a less invasive and lower-risk cure continues.

The more common treatment protocol is still through antiretroviral therapy (ART). These drugs stop the virus from replicating in the body. Treatment is personalized based on each individual’s response to the drug. It usually involves a combination of drugs because the HIV virus can easily become resistant [7]. The HIV drug combination is designed to block the HIV virus at different stages of its life cycle. According to the NIH, there are over 30 antiretroviral drugs.

 

Elite Controllers and Natural Superpower Against HIV

 

There are a handful of people who, despite being infected with HIV, have no symptoms and need no retroviral medications. This group of HIV-resistant individuals has natural immunity that is quite powerful in defeating HIV and are known as ‘elite controllers.’  

One such ‘elite controller’ is Loreen Willenberg, a Californian in her 60s. Her immune system is so incredibly potent that Loreen is classified as an ‘exceptional elite controller.’ Loreen has had no HIV disease progression for almost 30 years! Researchers believe that, in elite controllers, 60% of the HIV genes are clustered in genetic areas known as ‘gene deserts.’ The immune systems of elite controllers kill all other HIV cells. The ones allowed to live contain inactive DNA which cannot replicate [8].

 

Why Don’t We Have an AIDS Vaccine Yet?

 

The biggest challenge to developing an HIV vaccine is that HIV can hide its genetic code in its host DNA – unlike other viruses. They bury into the immune cells (T-cells) and, once there, remain hidden from the immune system and never leave. The virus is also extremely wily. It is highly adaptable and creates multiple variants within each individual, and evades immune response.

Sometimes hope arrives in a strange package. In 2020 and 2021, the world poured all its energy, resources, and funding to develop the Coronavirus vaccines. Scientists who worked on the COVID-19 mRNA vaccines came from the world of HIV research. Sure, this effort temporarily diverted attention away from HIV. However, the fast-tracking of the mRNA vaccine technology could potentially help in the fight against HIV.

 

Future of AIDS and HIV Research

 

The world continues to need more such scientific breakthroughs in the field of HIV and AIDS research. We need all science-related hands on deck. This includes cross-functional collaboration between genetic scientists, oncologists, immunologists, infectious disease specialists, virologists, epidemiologists, and more.

Researchers are working on finding an effective HIV cure that is relatively lower risk and can be made available across the globe. However, prevention is the best way to lower the incidence and curb the spread of the virus; a vaccine is our best shot.

Apart from a preventive vaccine, we also need a therapeutic vaccine to offer people already infected with HIV. Currently, people living with HIV have been resigned to taking multiple medications every single day for the rest of their lives. This can prove expensive, and compliance with medication protocols can vary from patient to patient. However, ideally, a therapeutic vaccine could help stimulate the immune system and eliminate the need for sustained therapy.

Aside from that, there are a few days that are dedicated each year to encourage awareness, prevention, treatment, health, and therapy. These days are HIV testing day and National HIV testing, AIDS awareness day, World AIDS day.

References
[1] P. Zhang, E. Narayan, and Q. Liu, “A multiclade env–gag VLP mRNA vaccine elicits tier-2 HIV-1-neutralizing antibodies and reduces the risk of heterologous SHIV infection in macaques.,” Nature Medicine, vol. 27, p. 2234–2245, 2021.
[2] Centers for Disease Control and Prevention (CDC), “HIV: AIDS and Opportunistic Infections,” 20 05 2021. [Online]. Available: https://www.cdc.gov/hiv/basics/livingwithhiv/opportunisticinfections.html. [Accessed 21 12 2021].
[3] hiv.gov, “What Are HIV and AIDS?,” U.S. Department of Health & Human Services. Supported by the Minority HIV/AIDS Fund, 05 06 2020. [Online]. Available: https://www.hiv.gov/hiv-basics/overview/about-hiv-and-aids/what-are-hiv-and-aids. [Accessed 20 12 2021].
[4] Mayo Clinic, “HIV/AIDS: Symptoms and Causes,” 13 02 2020. [Online]. Available: https://www.mayoclinic.org/diseases-conditions/hiv-aids/symptoms-causes/syc-20373524. [Accessed 13 02 2021].
[5] HIVInfo.NIH.gov, “HIV Overview: The Stages of HIV Infection,” NIH, 20 08 2021. [Online]. Available: https://hivinfo.nih.gov/understanding-hiv/fact-sheets/stages-hiv-infection. [Accessed 21 12 2021].
[6] A. Mandavilli, “The ‘London Patient,’ Cured of H.I.V., Reveals His Identity,” New York Times, 09 11 2020. [Online]. Available: https://www.nytimes.com/2020/03/09/health/hiv-aids-london-patient-castillejo.html. [Accessed 21 12 2021].
[7] “Treatment: HIV and AIDS,” NHS UK, 22 04 2021. [Online]. Available: https://www.nhs.uk/conditions/hiv-and-aids/treatment/. [Accessed 21 12 2021].
[8] C. Jiang, X. Lian and C. Gao, “Distinct viral reservoirs in individuals with spontaneous control of HIV-1,” Nature, vol. 585, p. 261–267, 2020.
[9] Z. Tuofu, B. T. Korber, A. J. Nahmias, E. Hooper, P. M. Sharp and D. D. Ho, “An African HIV-1 sequence from 1959 and implications for the origin of the epidemic,” Nature, vol. 391, p. 594–597, 1998.
Author
Chandana Balasubramanian

Chandana Balasubramanian is an experienced healthcare executive who writes on the intersection of healthcare and technology. She is the President of Global Insight Advisory Network, and has a Masters degree in Biomedical Engineering from the University of Wisconsin-Madison, USA.

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