World AIDS Day 

• Introduction

    Today is World AIDS Day, observed every year on December 1st to raise awareness about HIV/AIDS and to show support for people living with HIV/AIDS. The theme for World AIDS Day 2023 is "Let Communities Lead"³. This year's theme emphasizes the importance of empowering communities to lead the fight against AIDS. 

      HIV (Human Immunodeficiency Virus) is a virus that attacks the immune system, which is responsible for fighting off infections and diseases. AIDS (Acquired Immunodeficiency Syndrome) is a condition that occurs when the immune system is severely damaged by HIV, and the body is unable to fight off infections and diseases.

       There are many myths surrounding HIV/AIDS, which can lead to stigma and discrimination against people living with HIV/AIDS. It is important to debunk these myths and spread accurate information about HIV/AIDS. Some common myths include: HIV can be transmitted through casual contact, HIV only affects certain groups of people, and HIV can be cured. 

      Prevention is key when it comes to HIV/AIDS. Some ways to prevent HIV include: using condoms during sex, getting tested for HIV regularly, and taking pre-exposure prophylaxis (PrEP) if you are at high risk of getting HIV ¹. living with HIV/AIDS, it is important to seek medical care and treatment. Antiretroviral therapy (ART) can help people living with HIV/AIDS live long and healthy lives.

       On this World AIDS Day, let us remember those who have lost their lives to AIDS-related illnesses, show support for people living with HIV/AIDS, and work towards ending the AIDS epidemic.

• Epidemiology

        According to the National AIDS Control Organization (NACO) in India, the adult (15-49 years) prevalence of HIV in India is 0.21% ¹. In 2022, globally, 38 million people were living with HIV, and 1.5 million people were newly infected with HIV. AIDS-related deaths have been reduced by 69% since the peak in 2004. 

          According to the World Health Organization (WHO), an estimated 39.0 million people were living with HIV at the end of 2022, with two-thirds of them in the WHO African Region. The global prevalence of HIV has increased from 31.0 million in 2002 to 35.3 million in 2012, while global incidence has decreased from 3.3 million in 2002 to 2.3 million in 2012. In India, the adult (15-49 years) prevalence of HIV is 0.21% ¹. 

       India has the third-highest number of people living with HIV/AIDS in the world, with an estimated 2.1million people affected as of 2021. The Indian government has implemented several initiatives to combat the spread of HIV/AIDS, including the National AIDS Control Program (NACP). The NACP aims to reduce the prevalence of HIV/AIDS in India by increasing awareness, promoting safe sex practices, and providing access to antiretroviral therapy.

• Pathophysiology and Pathogenesis of HIV/AIDS

       HIV (Human Immunodeficiency Virus) is a virus that attacks the immune system, which is

responsible for fighting off infections and diseases. HIV is transmitted through unprotected sexual activity, blood transfusions, hypodermic needles, and from mother to child.

        The pathophysiology of HIV/AIDS involves the replication of the virus inside and killing of T helper cells, which are required for almost all adaptive immune responses. There is an initial period of influenza-like illness, and then a latent, asymptomatic phase. When the CD4 lymphocyte count falls below 200 cells/ml of blood, the HIV host has progressed to AIDS, a condition characterized by deficiency in cell-mediated immunity and the resulting increased susceptibility to opportunistic infections and certain forms of cancer.

      The pathogenesis of HIV/AIDS is driven by CD4 T-cell depletion and chronic inflammation. Infection of the cells of the CNS cause acute aseptic meningitis, subacute encephalitis, vacuolar myelopathy and peripheral neuropathy. Later it leads to even AIDS dementia complex.

• The symptoms of HIV/AIDS

        The symptoms of HIV/AIDS can vary depending on the stage of infection. During the initial stage, which is known as acute HIV infection, some people may experience flu-like symptoms such as fever, headache, muscle aches, rash, and swollen lymph nodes. However, some people may not experience any symptoms during this stage.

      During the second stage, which is known as clinical latent infection, the virus is still present in the body and in white blood cells, but many people may not have any symptoms or infections during this time. This stage can last for many years if the person is receiving antiretroviral therapy (ART). 

          During the third stage, which is known as symptomatic HIV infection, the virus continues to multiply and destroy immune cells, which can lead to mild infections or chronic signs and symptoms such as fatigue, fever, swollen lymph nodes, diarrhea, weight loss, oral yeast infection, shingles, pneumonia, and more.

        If left untreated, HIV can progress to the fourth stage, which is known as AIDS. At this stage, the immune system is severely damaged, and major opportunistic infections and cancers may develop. It's important to note that some people may not experience any symptoms for many years after being infected with HIV.

• Diagnosis

HIV can be diagnosed through blood or saliva testing. Available tests include:

        Antigen/antibody tests: These tests usually involve drawing blood from a vein. Antigens are substances on the HIV virus itself and are usually detectable — a positive test — in the blood within a few weeks after exposure to HIV. Antibodies are produced by your immune system when it’s exposed to HIV. It can take weeks to months for antibodies to become detectable. The combination antigen/antibody tests can take 2 to 6 weeks after exposure to become positive.

        Antibody tests: These tests look for antibodies to HIV in blood or saliva. Most rapid HIV tests, including self-tests done at home, are antibody tests. Antibody tests can take 3 to 12 weeks after you’re exposed to become positive. 

        Nucleic acid tests (NATs): These tests look for the actual virus in your blood (viral load). They also involve blood drawn from a vein. If you might have been exposed to HIV within the past few weeks, your health care provider may recommend NAT. NAT will be the first test to become positive after exposure to HIV 1.

• Treatment

          There is currently no cure for HIV/AIDS, but there are several treatments available that can help manage the disease and improve the quality of life for people living with HIV/AIDS. Antiretroviral therapy (ART) is the most common treatment for HIV/AIDS. ART involves taking a combination of medications that target different stages of the HIV life cycle. The goal of ART is to reduce the amount of virus in the body (viral load) to undetectable levels, which can help prevent the progression of HIV/AIDS and reduce the risk of transmission to others.

        The specific medications used in ART can vary depending on the individual's health status, the stage of the disease, and other factors. Some common classes of medications used in ART include:

1. Nucleoside reverse transcriptase inhibitors (NRTIs): These drugs block the reverse transcriptase enzyme, which is needed by HIV to replicate.
2. Non-nucleoside reverse transcriptase inhibitors (NNRTIs): These drugs also block the reverse transcriptase enzyme, but in a different way than NRTIs.
3. Protease inhibitors (PIs): These drugs block the protease enzyme, which is needed by HIV to produce new viruses.
4. Integrase inhibitors: These drugs block the integrase enzyme, which is needed by HIV to insert its genetic material into the DNA of human cells.
5. Entry inhibitors: These drugs block the entry of HIV into human cells.
6. Fusion inhibitors: These drugs block the fusion of HIV with human cells.

        It's important to note that ART can have side effects, and the specific side effects can vary depending on the medications used. It's important to work closely with a healthcare provider to monitor the effectiveness of ART and manage any side effects.

• Prevention

         Primordial prevention refers to the prevention of the social, economic, and environmental conditions that contribute to the spread of HIV/AIDS. Some examples of primordial prevention strategies include:

1. Poverty Reduction: Poverty is a major factor that contributes to the spread of HIV/AIDS. Poverty reduction strategies such as increasing access to education, healthcare, and employment opportunities can help to reduce the spread of HIV/AIDS.
2. Gender Equality: Gender inequality is another factor that contributes to the spread of HIV/AIDS. Promoting gender equality and empowering women and girls can help to reduce the spread of HIV/AIDS.
3. Stigma reduction: Stigma and discrimination against people living with HIV/AIDS can prevent them from seeking testing, treatment, and care services. Stigma reduction strategies can help to reduce the spread of HIV/AIDS.

         Preventing HIV transmission is crucial to reduce the number of new HIV infections. Here are some ways to prevent HIV at different levels:

1. Primary prevention: This involves taking steps to prevent HIV transmission before exposure to the virus. Some primary prevention strategies include:
• Abstinence: Not having sex is the most effective way to prevent HIV transmission.
• Condom use: Using condoms correctly and consistently during sex can reduce the risk of HIV transmission.
• Pre-exposure prophylaxis (PrEP): PrEP is a daily pill that can reduce the risk of HIV transmission by up to 99% when taken consistently.
• Needle exchange programs: These programs provide sterile needles and syringes to people who inject drugs to reduce the risk of HIV transmission.
2. Secondary prevention: This involves taking steps to prevent HIV transmission after exposure to the virus. Some secondary prevention strategies include: 
• Post-exposure prophylaxis (PEP): PEP is a medication that can prevent HIV transmission if taken within 72 hours of exposure to the virus. 
• Treatment as prevention (TasP): TasP involves taking antiretroviral therapy (ART) to suppress the virus and reduce the risk of HIV transmission.
3. Tertiary prevention: This involves taking steps to prevent the progression of HIV to AIDS and to improve the quality of life for people living with HIV/AIDS. Some tertiary prevention strategies include: 
• Antiretroviral therapy (ART): ART involves taking a combination of medications to suppress the virus and stop the progression of the disease.
• Support services: People living with HIV/AIDS may benefit from support services such as counseling, mental health services, and peer support groups.

• HIV and Tuberculosis

Tuberculosis (TB) is a disease caused by a bacterium called Mycobacterium tuberculosis. The TB bacterium can spread from person to person through the air. TB usually affects the lungs, but it can affect any part of the body, including the kidneys, spine, or brain. If not treated, TB can cause death. HIV weakens the immune system, increasing the risk of TB in people with HIV. Infection with both HIV and TB is called HIV/TB coinfection. Untreated latent TB infection is more likely to advance to TB disease in people with HIV than in people without HIV. In people with HIV, TB disease is considered an AIDS-  defining condition. AIDS-defining conditions are infections and cancers that are life-threatening in people with HIV. Treatment with HIV medicines is called antiretroviral therapy (ART). HIV medicines protect the immune system and prevent HIV from advancing to acquired immunodeficiency syndrome (AIDS). In people with HIV and latent TB infection, treatment with HIV and TB medicines reduces the

chances that latent TB infection will advance to TB disease.

• Key Message

     On World HIV Day, we remember the millions of people who have lost their lives to HIV/AIDS and show our support for those living with the virus. This day also provides an opportunity to reflect on the progress made in the fight against HIV/AIDS and to renew our commitment to ending the epidemic. 

       To prevent HIV transmission, it is important to raise awareness about the link between HIV/AIDS and TB and to ensure that people living with HIV/AIDS have access to the necessary screening, treatment, and care services to prevent and manage TB. It is also important to take steps to prevent HIV transmission before and after exposure to the virus, such as using condoms correctly and consistently during sex, taking pre-exposure prophylaxis (PrEP), and taking post-exposure prophylaxis (PEP) if you have been exposed to the virus.

       We can still end AIDS by 2030, but only if we act courageously and together to take on inequalities. We know what works from seeing brilliant responses in some places – but we need to apply that everywhere for everyone. We have an effective strategy that leaders agreed this year at the UN – but it needs to be implemented in full. The transformative approach that we need to end AIDS will also protect the world against future pandemics. The measures needed to tackle inequalities include community-led and people-centered infrastructure, equitable access to medicines, vaccines and health technologies, human rights, elevating essential workers, and providing them with the resources and tools they need, and people-centered data systems that highlight inequalities.

Reference

1. World AIDS Day 2023 - World Health Organization. https://pmnch.who.int/news-and-events/events/item/2023/12/01/international-days/world-aids-day-2023.
2. Pathophysiology of HIV/AIDS -Wikipedia.https://en.wikipedia.org/wiki/Pathophysiology_of_HIV/AIDS.
3. HIV/AIDS - Symptoms and causes - Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/hiv-aids/symptoms-causes/syc-20373524.
4. Diagnosis of HIV/AIDS - Wikipedia. https://en.wikipedia.org/wiki/Diagnosis_of_HIV/AIDS.
5. HIV/AIDS - Diagnosis and treatment - Mayo Clinic. https://www.mayoclinic.org/diseases-conditions/hiv-aids/diagnosis-treatment/drc-20373531.
6. Guidelines for the Prevention and Treatment of Opportunistic Infections ....https://clinicalinfo.hiv.gov/en/guidelines/hiv-clinical-guidelines-adult-and-adolescent-opportunistic-infections/prophylaxis-prevent-first-episode.
7. HIV and Tuberculosis - World Health Organization (WHO).https://www.who.int/westernpacific/health-topics/hiv-aids/hiv-and-tuberculosis.

Regards and Thanks,

Dr. (Prof)Rajendra T. Nanavare

Chest Physician, Mumbai.