Why it’s so hard to cure HIV/AIDS - Janet Iwasa

Summary

In 2008, a man was uniquely cured of HIV, a milestone in over 70 million cases. HIV, a retrovirus, infects immune cells, particularly helper T cells, leading to AIDS if untreated. While antiretroviral therapy can manage HIV and prevent AIDS, it requires lifelong medication adherence. Challenges like global access disparities persist, yet research into activating latent HIV for destruction and gene-editing to remove viral DNA offers hope for a universal cure.

Takeaways

• 🌟 In 2008, a man was cured of HIV, marking the first and only known case to date.
• 🔬 HIV primarily spreads through bodily fluids, with unprotected sex and contaminated needles being the main modes of transmission.
• 🏥 HIV targets the immune system, specifically helper T cells, which are crucial for defending against infections.
• 💊 Antiretroviral therapy can manage HIV levels and prevent progression to AIDS, allowing most HIV-positive individuals to lead long, healthy lives.
• 🔄 HIV is a retrovirus that integrates its genetic material into the host cell's DNA, complicating eradication efforts.
• 🛑 Current drugs can't reach HIV that hides in the DNA of healthy T cells, which can remain dormant for years before reactivating.
• 🌐 Access to life-saving antiretroviral therapies is limited, especially in Sub-Saharan Africa, where only one in three HIV-positive patients received treatment in 2012.
• 🚫 Political, economic, and cultural barriers make it difficult to implement effective HIV prevention and treatment strategies worldwide.
• 🔬 Researchers are exploring new approaches to a cure, including drugs that activate HIV in dormant cells and genetic tools to remove HIV DNA from cell genomes.
• 💡 The existence of a single cured case offers hope and evidence that an HIV cure is possible, potentially leading to a definitive solution.

Q & A

What was the significant event that occurred in 2008 regarding HIV?

In 2008, a man was cured of HIV, marking the first and, so far, the only instance of a cure in over 70 million cases.

Why is HIV difficult to cure compared to diseases like malaria and hepatitis C?

HIV is difficult to cure because it is a retrovirus that can integrate its genetic code into the genome of infected cells, making it challenging to eliminate completely without affecting healthy cells.

How does HIV primarily spread and what are the common modes of transmission?

HIV spreads through exchanges of bodily fluids, with unprotected sex and contaminated needles being the leading causes of transmission. It cannot spread through air, water, or casual contact.

Which immune cells are targeted by HIV and what is the role of these cells in the body?

HIV particularly targets helper T cells, which are part of the immune system and help defend the body against bacterial and fungal infections.

What are the symptoms experienced during the first stage of HIV infection?

During the first stage of HIV infection, patients often experience flu-like symptoms, but they are typically not yet in mortal danger.

What is AIDS and how does it relate to HIV infection?

AIDS is the stage of HIV infection when T cell counts drop too low, putting patients in serious danger of contracting deadly infections that a healthy immune system can normally handle.

How do antiretroviral drugs help manage HIV and prevent the progression to AIDS?

Antiretroviral drugs are highly effective at managing levels of HIV and preventing T cell counts from getting low enough for the disease to progress to AIDS. They work by preventing the viral genome from being copied and incorporated into a host cell's DNA or by preventing the virus from maturing or assembling.

Why must HIV-positive patients continue taking their medication for life?

HIV-positive patients must keep taking their drugs for the rest of their lives because without them, the virus can make a deadly comeback, as it can hide in the DNA of healthy T cells and reactivate.

What is the current global access to antiretroviral therapy for HIV patients?

In 2012, antiretrovirals reached only about one in three HIV-positive patients in Sub-Saharan Africa, which accounts for over 70% of HIV patients worldwide, indicating a significant gap in access to life-saving therapies.

What are some of the barriers to effective HIV prevention and treatment?

Effective prevention and treatment of HIV are hindered by a mix of political, economic, and cultural barriers, making it difficult to ensure widespread access to therapies and prevention methods.

What are some promising research approaches towards finding a cure for HIV?

Promising research approaches include using a drug to activate all cells harboring the HIV genetic information to flush the virus out into the open, and using genetic tools to cut the HIV DNA out of cells' genomes altogether.

Outlines

00:00

🩺 HIV Infection and the Quest for a Cure

In 2008, a landmark event occurred with the first and only known cure of HIV. Despite advances in medicine that can cure diseases like malaria and hepatitis C, HIV remains a challenge due to its ability to integrate into the host's DNA. HIV primarily spreads through bodily fluids, affecting individuals regardless of age, sexual orientation, gender, or race. It targets helper T cells, which are crucial for immune defense, leading to a weakened immune system and the potential progression to AIDS. Antiretroviral therapy can manage HIV levels and prevent AIDS, but it requires lifelong adherence, and the virus can hide in latent T cells, complicating eradication. Additionally, access to these therapies is limited, particularly in Sub-Saharan Africa, where only one in three HIV-positive patients had access to antiretrovirals in 2012. Despite these challenges, research is ongoing, with approaches such as activating HIV genetic information in cells to expose the virus to current drugs, and using genetic tools to remove HIV DNA from cell genomes, offering hope for a universal cure.

Keywords

💡HIV

HIV, or Human Immunodeficiency Virus, is a virus that attacks the immune system and, if left untreated, can progress to AIDS. In the video, HIV is the central topic, with a focus on its transmission, infection process, and the challenges it presents in terms of finding a cure. The script mentions that HIV infects helper T cells, which are crucial for the body's defense against infections.

💡AIDS

AIDS, or Acquired Immunodeficiency Syndrome, is the final stage of HIV infection, where the immune system is severely compromised. The video explains that AIDS occurs when T cell counts drop too low, making the body vulnerable to infections that a healthy immune system would normally handle. The script highlights the progression from HIV to AIDS and the importance of treatment to prevent this.

💡Antiretroviral therapy

Antiretroviral therapy (ART) is a treatment for HIV that uses drugs to prevent the virus from multiplying and to keep the virus under control. The video discusses the effectiveness of ART in managing HIV levels and preventing the progression to AIDS. It also mentions the necessity for lifelong adherence to these drugs to maintain their benefits.

💡Helper T cells

Helper T cells, also known as CD4 cells, are a type of white blood cell that plays a critical role in the immune system. The video script explains that HIV targets these cells, leading to a weakened immune response. The health of an HIV-positive individual is often measured by the count of these cells.

💡Retrovirus

A retrovirus is a type of virus that can reverse transcribe its RNA into DNA and integrate it into the host's genome. The video script uses the term 'retrovirus' to describe HIV, emphasizing how it can write its genetic code into the DNA of infected cells, which is a key factor in its ability to evade the immune system and the difficulty in curing the infection.

💡Transmission

Transmission refers to the spread of a disease from one person to another. In the context of the video, HIV transmission is discussed as occurring through the exchange of bodily fluids, with unprotected sex and contaminated needles mentioned as leading causes. The script clarifies that HIV cannot spread through casual contact like air or water.

💡Dormant virus

A dormant virus is one that is not actively replicating but remains in a state of inactivity within the host's cells. The video script explains that HIV can become dormant within T cells, which can later reactivate and start producing the virus again, complicating efforts to cure the infection.

💡Genetic tools

Genetic tools refer to techniques or technologies used to manipulate or modify genetic material. The video script mentions the use of genetic tools as a potential approach to curing HIV, by cutting the HIV DNA out of the host cell's genome, which could eliminate the virus from the body.

💡Cure

A cure for a disease is a treatment that completely removes the disease from the body and restores health. The video script discusses the significance of the first and only known case of an HIV cure, and the ongoing research efforts to develop a universal cure. The term 'cure' is central to the video's message of hope and the pursuit of a definitive solution to HIV.

💡Sub-Saharan Africa

Sub-Saharan Africa is a region that includes the countries of Africa that lie below the Sahara Desert. The video script highlights the disproportionate impact of HIV on this region, noting that it accounts for over 70% of HIV patients worldwide and that access to life-saving antiretroviral therapies is limited.

💡Barriers to treatment

Barriers to treatment refer to the obstacles that prevent individuals from accessing or adhering to necessary medical care. The video script discusses various political, economic, and cultural barriers that make it difficult to effectively prevent and treat HIV, particularly in regions like Sub-Saharan Africa.

Highlights

In 2008, a man was cured of HIV, marking the first and only instance to date.

HIV has been diagnosed in over 70 million cases, yet a cure remains elusive.

HIV primarily spreads through bodily fluids, with unprotected sex and contaminated needles as the main transmission routes.

HIV cannot spread through air, water, or casual contact.

HIV infects cells of the immune system, particularly helper T cells.

HIV is a retrovirus that inserts its genetic code into the host cell's genome.

During the first stage of HIV infection, the virus replicates rapidly within helper T cells, causing flu-like symptoms.

The virus can remain dormant in a small percentage of T cells for years.

When T cell counts drop significantly, patients enter the AIDS stage, becoming vulnerable to deadly infections.

Antiretroviral therapy can effectively manage HIV levels and prevent progression to AIDS.

HIV-positive individuals on antiretroviral therapy can expect to live long and healthy lives.

Patients must take antiretroviral drugs for life to prevent a resurgence of the virus.

Antiretroviral drugs work by preventing the viral genome from being copied or by inhibiting the virus's maturation and assembly.

HIV can hide in the DNA of healthy T cells, making it difficult to eradicate completely.

Access to life-saving antiretroviral therapy is limited, especially in Sub-Saharan Africa.

Political, economic, and cultural barriers complicate HIV prevention and treatment efforts.

Researchers are exploring new approaches to activate and eliminate HIV from cells.

Genetic tools are being investigated to remove HIV DNA from infected cells.

The single cure case gives hope that an HIV cure is possible.

The pursuit of an HIV cure is ongoing, with new research providing reasons for optimism.

Transcripts

In 2008, something incredible happened: a man was cured of HIV.

In over 70 million HIV cases, that was a first and, so far, a last.

We don't yet understand exactly how he was cured.

We can cure people of various diseases, such as malaria and hepatitis C,

so why can't we cure HIV?

Well, first let's examine how HIV infects people

and progresses into AIDS.

HIV spreads through exchanges of bodily fluids.

Unprotected sex and contaminated needles are the leading cause of transmission.

It, fortunately, cannot spread through air, water, or casual contact.

Individuals of any age, sexual orientation, gender and race

can contract HIV.

Once inside the body, HIV infects cells that are part of the immune system.

It particularly targets helper T cells,

which help defend the body against bacterial and fungal infections.

HIV is a retrovirus,

which means it can write its genetic code into the genome of infected cells,

co-opting them into making more copies of itself.

During the first stage of HIV infection,

the virus replicates within helper T cells,

destroying many of them in the process.

During this stage, patients often experience flu-like symptoms,

but are typically not yet in mortal danger.

However, for a period ranging from a few months to several years,

during which time the patient may look and feel completely healthy,

the virus continues to replicate and destroy T cells.

When T cell counts drop too low,

patients are in serious danger of contracting deadly infections

that healthy immune systems can normally handle.

This stage of HIV infection is known as AIDS.

The good news is there are drugs that are highly effective

at managing levels of HIV

and preventing T cell counts from getting low enough

for the disease to progress to AIDS.

With antiretroviral therapy,

most HIV-positive people can expect to live long and healthy lives,

and are much less likely to infect others.

However, there are two major catches.

One is that HIV-positive patients must keep taking their drugs

for the rest of their lives.

Without them, the virus can make a deadly comeback.

So, how do these drugs work?

The most commonly prescribed ones prevent the viral genome from being copied

and incorporated into a host cell's DNA.

Other drugs prevent the virus from maturing or assembling,

causing HIV to be unable to infect new cells in the body.

But HIV hides out somewhere our current drugs cannot reach it:

inside the DNA of healthy T cells.

Most T cells die shortly after being infected with HIV.

But in a tiny percentage,

the instructions for building more HIV viruses lies dormant,

sometimes for years.

So even if we could wipe out every HIV virus from an infected person's body,

one of those T cells could activate and start spreading the virus again.

The other major catch is that not everyone in the world has access to the therapies

that could save their lives.

In Sub-Saharan Africa, which accounts for over 70% of HIV patients worldwide,

antiretrovirals reached only about one in three HIV-positive patients in 2012.

There is no easy answer to this problem.

A mix of political, economic and cultural barriers

makes effective prevention and treatment difficult.

And even in the U.S., HIV still claims more than 10,000 lives per year.

However, there is ample cause for hope.

Researchers may be closer than ever to developing a true cure.

One research approach involves

using a drug to activate all cells harboring the HIV genetic information.

This would both destroy those cells and flush the virus out into the open,

where our current drugs are effective.

Another is looking to use genetic tools

to cut the HIV DNA out of cells genomes altogether.

And while one cure out of 70 million cases may seem like terrible odds,

one is immeasurably better than zero.

We now know that a cure is possible,

and that may give us what we need to beat HIV for good.