Acquired Immunodeficiency Syndrome (AIDS) is a chronic, potentially life-threatening condition caused by the human immunodeficiency virus (HIV). First recognized in 1981, AIDS has become a global pandemic, affecting millions worldwide. HIV attacks the body’s immune system, specifically CD4 cells (T helper cells), weakening the body’s ability to fight off infections and certain cancers. While there is currently no cure for HIV infection, advancements in antiretroviral therapy (ART) have significantly improved the quality of life and life expectancy of people living with HIV, transforming AIDS from a rapidly fatal disease to a manageable chronic condition. Understanding HIV and AIDS HIV (Human Immunodeficiency Virus) is a retrovirus that replicates within human cells, specifically targeting CD4+ T cells. This destruction of CD4+ T cells progressively weakens the immune system, making individuals susceptible to opportunistic infections and cancers. AIDS is diagnosed when the CD4+ T cell count drops below 200 cells per microliter of blood, or when certain opportunistic infections develop. Modes of Transmission HIV is transmitted through specific bodily fluids: Sexual Contact: Unprotected vaginal or anal sex. Blood Transfusion: Receiving contaminated blood or blood products (rare in developed countries due to screening). Sharing Needles: Injecting drug use with shared needles. Mother-to-Child Transmission: During pregnancy, childbirth, or breastfeeding. Other: Rarely, through organ transplantation or accidental needle sticks. HIV is not transmitted through casual contact such as hugging, shaking hands, sharing utensils, or insect bites. Stages of HIV Infection HIV infection typically progresses through three stages: Acute HIV Infection: Occurs within 2-4 weeks of infection. Many people experience flu-like symptoms. Clinical Latency: Also known as chronic HIV infection. The virus continues to replicate but at low levels. Individuals may be asymptomatic for years. AIDS: The most severe stage of HIV infection. The immune system is severely damaged, leading to opportunistic infections and cancers. Prevention Strategies Effective prevention strategies include: Safe Sex Practices: Consistent and correct use of condoms. Pre-Exposure Prophylaxis (PrEP): Taking antiretroviral medications before potential exposure to HIV. Post-Exposure Prophylaxis (PEP): Taking antiretroviral medications after potential exposure to HIV. Needle Exchange Programs: Providing sterile needles to injecting drug users. Testing and Counseling: Regular HIV testing and counseling. Treatment as Prevention (TasP): Individuals with HIV who achieve and maintain an undetectable viral load through ART cannot sexually transmit the virus to others. Treatment Options Antiretroviral Therapy (ART) involves a combination of medications that suppress HIV replication. ART does not cure HIV, but it can significantly improve the health and life expectancy of people living with HIV. Current ART regimens typically involve a combination of drugs from different classes, such as: Nucleoside/Nucleotide Reverse Transcriptase Inhibitors (NRTIs) Non-Nucleoside Reverse Transcriptase Inhibitors (NNRTIs) Protease Inhibitors (PIs) Integrase Inhibitors (INSTIs) Global Efforts Global efforts to combat AIDS are led by organizations such as: UNAIDS: The Joint United Nations Programme on HIV/AIDS. World Health Organization (WHO): Provides technical guidance and support. Global Fund to Fight AIDS, Tuberculosis and Malaria: Provides funding for prevention and treatment programs. The National AIDS Control Programme (NACP) in India, launched in 1992, has been instrumental in reducing the prevalence of HIV and improving access to treatment. AIDS remains a significant global health challenge, but substantial progress has been made in prevention, treatment, and care. Continued research, increased access to ART, and sustained prevention efforts are crucial to ending the AIDS epidemic. Addressing stigma and discrimination, promoting testing, and ensuring equitable access to healthcare services are essential components of a comprehensive response. The focus must remain on achieving the UNAIDS 95-95-95 targets – 95% of people living with HIV knowing their status, 95% of those diagnosed receiving treatment, and 95% of those on treatment achieving viral suppression – to ultimately eliminate HIV as a public health threat.

AIDS: Causes, Symptoms & Prevention | UPSC Mains ZOOLOGY-PAPER-I 2024

AIDS

How to Approach

The question asks for a comprehensive note on AIDS. A good answer should define AIDS, detail its causative agent (HIV), explain the modes of transmission, outline the stages of infection, discuss prevention strategies, and mention current treatment options and global efforts to combat the disease. The answer should be structured logically, covering the biological aspects, medical interventions, and public health implications. Focus on providing factual information and avoid overly simplistic explanations.

Understanding HIV and AIDS

HIV (Human Immunodeficiency Virus) is a retrovirus that replicates within human cells, specifically targeting CD4+ T cells. This destruction of CD4+ T cells progressively weakens the immune system, making individuals susceptible to opportunistic infections and cancers. AIDS is diagnosed when the CD4+ T cell count drops below 200 cells per microliter of blood, or when certain opportunistic infections develop.

Modes of Transmission

HIV is transmitted through specific bodily fluids:

Sexual Contact: Unprotected vaginal or anal sex.
Blood Transfusion: Receiving contaminated blood or blood products (rare in developed countries due to screening).
Sharing Needles: Injecting drug use with shared needles.
Mother-to-Child Transmission: During pregnancy, childbirth, or breastfeeding.
Other: Rarely, through organ transplantation or accidental needle sticks.

HIV is not transmitted through casual contact such as hugging, shaking hands, sharing utensils, or insect bites.

Stages of HIV Infection

HIV infection typically progresses through three stages:

Acute HIV Infection: Occurs within 2-4 weeks of infection. Many people experience flu-like symptoms.
Clinical Latency: Also known as chronic HIV infection. The virus continues to replicate but at low levels. Individuals may be asymptomatic for years.
AIDS: The most severe stage of HIV infection. The immune system is severely damaged, leading to opportunistic infections and cancers.

Prevention Strategies

Effective prevention strategies include:

Safe Sex Practices: Consistent and correct use of condoms.
Pre-Exposure Prophylaxis (PrEP): Taking antiretroviral medications before potential exposure to HIV.
Post-Exposure Prophylaxis (PEP): Taking antiretroviral medications after potential exposure to HIV.
Needle Exchange Programs: Providing sterile needles to injecting drug users.
Testing and Counseling: Regular HIV testing and counseling.
Treatment as Prevention (TasP): Individuals with HIV who achieve and maintain an undetectable viral load through ART cannot sexually transmit the virus to others.

Treatment Options

Antiretroviral Therapy (ART) involves a combination of medications that suppress HIV replication. ART does not cure HIV, but it can significantly improve the health and life expectancy of people living with HIV. Current ART regimens typically involve a combination of drugs from different classes, such as:

Nucleoside/Nucleotide Reverse Transcriptase Inhibitors (NRTIs)
Non-Nucleoside Reverse Transcriptase Inhibitors (NNRTIs)
Protease Inhibitors (PIs)
Integrase Inhibitors (INSTIs)

Global Efforts

Global efforts to combat AIDS are led by organizations such as:

UNAIDS: The Joint United Nations Programme on HIV/AIDS.
World Health Organization (WHO): Provides technical guidance and support.
Global Fund to Fight AIDS, Tuberculosis and Malaria: Provides funding for prevention and treatment programs.

The National AIDS Control Programme (NACP) in India, launched in 1992, has been instrumental in reducing the prevalence of HIV and improving access to treatment.

Additional Resources

Key Definitions

Opportunistic Infections

Infections that occur more often or are more severe in people with weakened immune systems, such as those with AIDS.

Viral Load

The amount of HIV in a sample of blood. An undetectable viral load means the amount of virus is too low to be detected by standard tests.

Key Statistics

Globally, 39.0 million people were living with HIV in 2022.

Source: UNAIDS, 2023

India has the fourth largest HIV epidemic globally, with an estimated 2.4 million people living with HIV in 2022.

Source: NACO, India (Knowledge cutoff 2023)

Examples

Magic Johnson

The public announcement of NBA star Magic Johnson’s HIV diagnosis in 1991 significantly raised awareness about AIDS and helped to reduce stigma surrounding the disease.

Frequently Asked Questions

▶Can HIV be cured?

Currently, there is no cure for HIV. However, with consistent antiretroviral therapy, people living with HIV can live long and healthy lives and prevent transmission of the virus to others.