What Is the Exact Cause of HIV?

Medically Reviewed on 6/3/2022
What Is the Exact Cause of HIV?
Because HIV suppresses the immune system, the predominant symptoms of this infection are those produced by other infections.

Human immunodeficiency virus (HIV) infection is caused by a retrovirus that affects the immune system, especially the CD4 blood cells that fight infections. As it replicates during acute HIV infection, HIV kills a large number of CD4 cells. This can induce flu-like symptoms in some people.

How does HIV spread?

HIV may spread from one person to another through:

  • A body fluid that contains active HIV
  • Direct bloodstream access (sometimes called a "port of entry")

Entry points into a person's bloodstream include:

  • An odd skin cut or a puncture wound
  • Mucous membrane (vagina or anus)

Body fluids that may contain an infectious amount of HIV include:

  • Blood
  • Breast milk
  • Seminal fluids (a.k.a. precum)
  • Rectal fluid
  • Semen
  • Vaginal fluid

You can potentially get HIV through the following:

  • Anal sex
  • Injecting drugs with shared needles or other equipment used to share drugs
  • Vaginal sex

However, infectious levels of HIV are not found in the following fluids:

  • Saliva
  • Tears
  • Urine

You cannot get HIV from the following:

  • Kissing
  • Mosquitoes
  • Skin-to-skin contact, including a massage
  • Sharing food or water
  • Toilet seats

If someone with HIV receives effective HIV therapy, the virus in their circulation is reduced to such a low level that they cannot transfer it to HIV-negative sexual partners.

3 stages of HIV

When people with human immunodeficiency virus (HIV) do not get therapy, they normally move through three phases. However, HIV medication can halt or stop the growth of the illness. With treatment advances, progression to stage III is less prevalent now than it was in the early days of HIV.

Three stages of HIV include:

  1. Stage I: Acute HIV infection
    • People have a high level of HIV in their blood which is extremely infectious.
    • Some people may experience flu-like symptoms. This is the body's normal reaction to infection. Some people, however, may not feel unwell soon after or at all.
    • If you experience flu-like symptoms and believe you may have been exposed to HIV, get medical attention and request an acute infection test.
    • Acute infection can only be diagnosed by antigen/antibody testing or nucleic acid tests.
  2. Stage II: Chronic HIV infection or asymptomatic HIV infection or clinical latency
    • HIV is still active although at very low levels. During this stage, people may not have any symptoms or become ill.
    • Without HIV medication, this stage might span a decade or longer, but some people may advance quicker.
    • During this stage, people can spread HIV.
    • At the end of this phase, the amount of HIV in the blood (known as the viral load) increases as the CD4 cell count decreases. As the virus levels in the body increase, the person may experience symptoms and progress to stage III.
    • People who take HIV medication as directed may never get to stage III.
  3. Stage III: Acquired immunodeficiency syndrome (AIDS)
    • This is the most dangerous stage of HIV infection.
    • People with AIDS have such weakened immune systems that they are susceptible to an increasing number of serious opportunistic infections.
    • When a person's CD4 cell count falls below 200 cells/mm or if they get specific opportunistic infections, they are diagnosed with AIDS.
    • People with AIDS might have a high viral load and be very infectious.
    • People with AIDS often live for three years without therapy.


A Timeline of the HIV/AIDS Pandemic See Slideshow

11 common symptoms of HIV

Because the human immunodeficiency virus (HIV) suppresses the immune system, the predominant symptoms of this infection are those produced by other infections. Because the body's immune system is unable to adequately protect, these illnesses increase and have a bigger effect on the body.

In reality, HIV symptoms may not appear for months or even years. However, some symptoms do arise in some circumstances, and they are as follows:

  1. Red rash over the body
  2. Tiredness/fatigue
  3. Sudden weight loss
  4. Joint pain
  5. Muscle ache
  6. Sweating at night
  7. Enlarged glands/swollen lymph nodes
  8. Sore throat
  9. Chills
  10. Weakness
  11. Mouth ulcers

11 common symptoms of AIDS

Many of these symptoms are similar to those of the flu or a regular cold, making it difficult to diagnose HIV right away. There may be no symptoms at all in other circumstances. In this case, the virus slowly deteriorates the body and its organs for years before it is detected. 

Eleven common symptoms of acquired immunodeficiency syndrome (AIDS) include:

  1. Chronic diarrhea
  2. White spots on the tongue and mouth
  3. Dry cough
  4. Blurred vision
  5. Swollen glands
  6. Fever lasting for weeks
  7. Permanent tiredness
  8. Shortness of breath
  9. Pneumonia
  10. Neurological disorders
  11. HIV health complications

10 complications of HIV and AIDS

When the body's immune system is in good working order, common illnesses of all types may be treated without serious difficulties. However, because HIV weakens the body's immune system, common illnesses have a more negative effect. These HIV health issues are known as opportunistic infections and are commonly used to detect late-stage HIV.

Ten possible complications of HIV/AIDS include:

  1. Invasive cervical cancer
  2. Cryptococcosis
  3. Cytomegalovirus disease
  4. Herpes simplex
  5. HIV-related encephalopathy
  6. Hodgkin and non-Hodgkin lymphoma
  7. Recurrent pneumonia
  8. Toxoplasmosis
  9. Wasting syndrome
  10. Kaposi’s sarcoma

5 treatment options for HIV

Your doctor will prescribe a course of therapy based on various factors. Medications, often known as antiretroviral therapy, act to inhibit viral replication, prevent or reverse immune system damage, regulate symptoms, and enhance the quality of life.

Doctors can use a combination of anti-human immunodeficiency virus (anti-HIV) medications to prevent the virus from multiplying and preserve your immune system. Multiple antiretroviral classes are available, each of which works in a different way to suppress HIV. 

People normally take two or three drugs from at least two distinct groups to ensure that the virus does not develop resistance to any one therapy.

Five treatment options for HIV or acquired immunodeficiency syndrome (AIDS) include:

  1. Nucleoside reverse transcriptase inhibitors or nucleotide reverse transcriptase inhibitors (NRTIs) or nukes:
    • HIV needs an enzyme called transcriptase to replicate itself in your body. NRTIs aims to prevent this enzyme from allowing the virus to replicate.
  2. Nonnucleoside reverse transcriptase inhibitors (NNRTIs) or nonnukes:
    • NNRTIs act similar to NRTIs in that they attach to and inhibit the enzyme used by HIV to replicate itself, stopping the cell from creating a new virus. 
  3. Entry inhibitors:
    • This class has two somewhat distinct strategies that both inhibit viral entrance into healthy immune cells (CD4 cells).
    • CCR5 inhibitors act by preventing HIV from binding to immune system receptors known as CCR5.
    • The fusion inhibitors prevent the virus from “fusing” with its targets by attaching to gp41 proteins on the cell surface.
  4. Protease inhibitors:
    • HIV breaks apart large protein chains known as polyproteins, which are then used to construct new viral particles and manufacture new viruses
    • Protease inhibitors are medications that prevent the protease enzyme from working.
  5. Integrase inhibitors:
    • Integrase inhibitors prevent HIV from integrating into the DNA of the cells it infects by inhibiting an enzyme known as “integrase.”

9 side effects of HIV and AIDS medication

Nine possible side effects of HIV/AIDS medications include:

  1. Headaches
  2. Occasional diarrhea
  3. The slow decline in kidney function
  4. Numbing of the fingers and toes
  5. Abnormalities in liver function 
  6. Abnormal redistribution of fat throughout your body
  7. Allergic reactions
  8. Liver dysfunction
  9. Pancreatitis

However, most of these problems tend to occur with the older drugs, and more serious effects would likely develop over a period. With newer drugs, there are far fewer side effects to worry about. In fact, many people report not experiencing any adverse effects at all.

What is the prognosis of HIV and AIDS?

As with many other disorders, early discovery allows for additional treatment options. There are medicines available today that can not only delay the rate at which HIV weakens the immune system but also keep HIV at bay so that the individual may live a normal life.

Sadly, there is no cure for HIV. Speak with your healthcare practitioner for further information about HIV/AIDS therapy and support system to cope during the treatment process.

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Medically Reviewed on 6/3/2022
Image Source: iStock image

What Is HIV? https://www.webmd.com/hiv-aids/understanding-aids-hiv-basics

Symptoms of HIV: https://www.hiv.gov/hiv-basics/overview/about-hiv-and-aids/symptoms-of-hiv



HIV & AIDS: https://my.clevelandclinic.org/health/diseases/4251-aids--hiv