AIDS and HIV - Causes, Symptoms & Prevention

Introduction to HIV and AIDS

HIV is the virus that attacks and destroys CD4 cells, which are a class of T lymphocytes important for the proper functioning of the immune system. Without treatment, HIV will cause many diseases and some cancers to occur over time. HIV is transmitted through certain body fluids, but not through casual contact, water, or air.

History Of HIV

An African chimpanzee species infected humans with HIV. According to studies, HIV may have spread from chimpanzees to humans as early as the late 1800s. Simian immunodeficiency virus (SIV) is the name of the virus that affects chimpanzees. It most likely spread to people when they killed these chimpanzees for food and came into touch with their infected blood. HIV progressively expanded over Africa over many years, then to other regions of the world.

Key Characteristics Of HIV

Read about the key characteristics of HIV:

• Weakened immune system

• CD4 cell destroyer

• Transmitted by some forms of body fluid

• Is not transmitted using casual contact, water or the atmosphere

Stages Of HIV Infection

• Stage I - Acute HIV infection - High amount of HIV present in the blood and show Flu-like symptoms.

• Stage II - Chronic HIV infection - Asymptomatic HIV infection or clinical latency are other names for this stage. The virus is still active. During this period, people may not show any symptoms or get ill, but they can still transmit HIV. Those who adhere to the recommended HIV treatment regimen may never enter Stage 3 (AIDS). This stage could continue for a decade or longer without HIV therapy, or it might move forward very quickly. The person may enter Stage 3 at this stage's conclusion due to an increase in the viral load of HIV in the blood.

• Stage III - AIDS (Acquired Immunodeficiency Syndrome) - The most advanced and severe stage of HIV.

Risk Factors for HIV/AIDS

People are more likely to get HIV when they engage in the following behaviours and circumstances:

• Sharing contaminated needles, syringes, and other injecting equipment and drug solutions when injecting drugs

• Engaging in vaginal sex without condom.

• Having another STD (Sexually Transmitted Diseases) like syphilis, herpes, chlamydia, gonorrhoea, and bacterial vaginosis

• Receiving unsafe injections, blood transfusions, and medical procedures that involve unsterile instruments.

What Is AIDS?

AIDS is the third and final stage of HIV infection. Most people infected with HIV do not develop AIDS. AIDS is diagnosed when the CD4 count of an HIV patient falls below 200 cells per cubic millimetre of blood or when certain opportunistic infections or cancers are present. If untreated, HIV may progress to AIDS in as long as 10 years.

Difference Between AIDS And HIV

One of the most common confusion: "Is AIDS and HIV the same?" The full forms of AIDS and HIV are Acquired Immunodeficiency Syndrome and Human Immunodeficiency Virus, respectively. We can conclude from the name that both are interdependent, meaning that while HIV is the virus causing the condition, AIDS represents the advanced stage of that infection.

Causes and Modes of Transmission

HIV is easily passed with the following body fluids. Here are some instances of

Symptoms of HIV and AIDS

• At 2-4 weeks post-exposure, acute manifestations of HIV infection are reported as flu-like symptoms, sometimes cycling on and off.

• If left untreated, HIV progresses to AIDS, which may exhibit some serious opportunistic infections and cancers in due course.

Diagnosis Of HIV

There are various tests to detect HIV including antibody tests, antibody/antigen tests, and NATs. The duration taken by the above tests for detecting HIV differs.

• HIV Tests

• Tests Types

• Antibody tests

• Antibody/antigen tests

• Nucleic acid tests (NAT)

Treatment and Management

• Antiretroviral therapy (ART) manages HIV transmission.

• ART retards viral replication, allows the healing process of the body but cannot eradicate HIV.

Prevention Strategies for HIV/AIDS

The prevention of AIDS and HIV is necessary as it can save a lot of lives that are lost due to the onset of AIDS and HIV. Some measures for the prevention of AIDS and HIV are as follows:

Exam Weightage and Question Types (NEET, CBSE, AIIMS, JIPMER)

This table will provide a view of the weightage assigned to the topic of HIV and AIDS in various entrance exams to help students understand and concentrate effectively on their study efforts.

Table of Types of Questions

This table provides a concise overview of the types of questions that may be asked regarding HIV and AIDS, helping students focus their studies effectively.

NEET MCQs on HIV And AID (With Answers and Explanations)

Q1. AIDS is caused by HIV. Among the following, which one is not a mode of transmission of HIV?

1. Transfusion of contaminated blood.

2. Sharing the infected needles.

3. Shaking hands with an infected person.

4. Sexual contact with infected persons.

Correct answer: 3) Shaking hands with an infected person.

Explanation:

The human immunodeficiency virus, or HIV, cannot be spread by handshaking, embracing, or sharing cutlery.

It is transmitted through:

• Unprotected intercourse with an infected individual.

• Distributing syringes or needles.

• Transfusion of blood that is contaminated.

• From an infected mother to her child while she is pregnant, giving birth, or nursing.

Hence, the correct answer is option 3) Shaking hands with infected persons.

Q2. In which blood corpuscles, the HIV undergoes replication and produces progeny viruses?

1. TH Cells

2. B–lymphocytes

3. Basophils

4. Eosinophils

Correct answer: 1) TH Cells

Explanation:

HIV (Human Immunodeficiency Virus) primarily infects and replicates in T-helper cells, which are a type of white blood cell involved in the immune response. HIV specifically targets CD4 receptors on the surface of T-helper cells. Once inside the T-helper cells, the virus replicates and produces progeny viruses, leading to the destruction of T-helper cells and the weakening of the immune system. This is why HIV infection can result in immunodeficiency and increased susceptibility to various infections and diseases.

Hence the correct answer is Option 1) TH Cells.

Q3. Choose the correct option regarding Retrovirus:

1. An RNA virus that synthesizes DNA during infection.

2. A DNA virus that synthesizes RNA during infection.

3. An ssDNA virus

4. A dsRNA virus

Correct answer: 1) An RNA virus that synthesizes DNA during infection.

Explanation:

Retrovirus Key Characteristics:

1. RNA Genetic Material: Retroviruses possess a single-stranded RNA genome as their genetic makeup.
2. Unusual Replication: They employ reverse transcription, a distinctive process wherein the RNA is transformed into complementary DNA (cDNA) using the reverse transcriptase enzyme, which inverts the standard DNA to RNA flow of genetic information.
3. Integration: An enzyme named integrase facilitates the insertion of this new DNA into the host cell's genome.
4. Dependence on Host: Obligate parasites, are unable to replicate independently, relying on host cells for their reproduction.
5. Notable Examples: Include HIV, the causative agent of AIDS, which specifically targets the human immune system.

Hence, the correct answer is option 1) An RNA virus that can synthesize DNA during infection.

Also Read:

• MCQs on HIV and AIDS

• Difference Between Innate and Adaptive Immunity

• Viral Diseases

FAQs on HIV And AIDS

How is HIV transmitted?

HIV (Human Immunodeficiency Virus) is transmitted through unprotected sexual contact with an infected person, sharing contaminated needles, transfusion of blood, and also to babies from the infected mother. It can also spread by the exchange of bodily fluids like blood, semen, and breast milk. HIV cannot be spread by casual contact like shaking hands, hugging, or sharing clothes.

How is HIV diagnosed?

HIV is diagnosed by detecting antibodies or antigens present in the blood. Some of the common tests that detect HIV are ELISA (Enzyme Linked Immunosorbent Assay) and rapid antibody test. If the first test is positive, it is further confirmed by a Western blot test or PCR (Polymerase Chain Reaction). This confirms the presence of viruses directly in the human body.

What is ART in HIV treatment?

The full form of ART is Antiretroviral Therapy. It uses a combination of medicines to manage HIV. Although, it does not cure HIV but helps to reduce the number of viruses. It also helps to make the immune system stronger to fight any infection, which generally becomes weak in HIV. It prevents HIV from progressing into its advanced level i.e. AIDS. ART is necessary in managing the HIV infection.

How can AIDS and HIV be prevented?

AIDS and HIV can be prevented by practicing safe sex using condoms, avoiding sharing needles from infected persons, safe blood transfusion, and regular HIV tests especially those who are at high risk. Pregnant women should consult doctors and take medicines to reduce the risk of passing HIV to the baby. Public awareness and education about HIV in schools also helps in prevention.

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