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The Facts About HIV/AIDS

Once a fatal diagnosis, HIV/AIDS can now be treated successfully, resulting in healthy outcomes.

A gloved hand holds a test tube full of blood labeled as human immunodeficiency virus.

The human immunodeficiency virus (HIV) and acquired immunodeficiency syndrome (AIDS) are chronic conditions that interfere with the body's ability to protect itself from infection and disease.

Fortunately, in the decades since the onset of the HIV/AIDS epidemic in the early 1980s, massive strides have been made in medical research, resulting in simpler, more successful treatment options.

What is HIV?

HIV is a sexually transmitted virus that can cause AIDS. The human immunodeficiency virus attacks and weakens the immune system by reducing the body's white blood cell count. The immune system is responsible for fighting infection and disease, so the damage caused by HIV leaves people more vulnerable to infections and diseases caused by bacteria, viruses and other rogue agents.

Thanks to modern medical treatments, people who seek treatment early and consistently adhere to prescribed treatment plans can live full, healthy lives, knowing they are protected from serious advancement of their condition or the development of AIDS.

Modern medical treatments make it possible for people with HIV to continue having a robust and fulfilling sex life without fear of passing the virus to their sexual partners.

What is AIDS?

Acquired immunodeficiency syndrome is the advanced stage of an HIV infection which develops when the body's immune system has been severely damaged by HIV. When this occurs, the body is unable to effectively protect itself from infection and disease, and becomes particularly vulnerable to opportunistic infections and related complications.

In 1987, the U.S. Food and Drug Administration (FDA) approved the use of azidothymidine (AZT), the first antiretroviral drug for the treatment of HIV/AIDS. Today, most people in the United States who have HIV never develop AIDS.

According to HIV.gov, managed by the U.S. Department of Health & Human Services, a person with HIV is considered to have developed AIDS when one of the following is true:

  • The number of their CD4 cells falls below 200 cells per cubic millimeter of blood (200 cells/mm3). In comparison, someone with a healthy immune system has CD4 counts between 500 and 1,600 cells/mm3. HIV attacks and destroys CD4 cells, or T cells, which are an important part of the immune system.
  • They develop one or more opportunistic infections regardless of their CD4 count.

Even in cases where HIV has advanced to AIDS, HIV medication can be lifesaving, though the greatest benefits come when someone begins medication soon after HIV diagnosis.

An individual who has AIDS and is not actively taking HIV medication is typically expected to survive about three years, unless they become infected with a serious opportunistic illness, in which case life expectancy in the absence of treatment decreases to about one year.

Facts and stats

Since the HIV/AIDS epidemic emerged in the 1980s, about 84.2 million people have been infected with HIV and about 40.1 million have died from HIV/AIDS-related illnesses, according to the World Health Organization (WHO). At the end of 2021, an estimated 38.4 million people around the world were living with HIV.

In the U.S., as of 2019, the most recent year for data, about 1.2 million people older than age 13 had HIV. As of 2018, it's estimated 700,000 people had died of HIV/AIDS since the beginning of the epidemic.

Though modern medical treatments have significantly improved the outlook of individuals living with treated HIV, people in areas of the world with little access to such treatments remain greatly affected by high mortality rates. According to the WHO, sub-Saharan Africa is the most severely affected region, accounting for more than two-thirds of people living with HIV globally.

The history of HIV/AIDS

Research suggests HIV was most likely passed from chimpanzees to humans in the 1920s. From there, it's believed the virus continued to exist at low levels in humans until the HIV/AIDS epidemic took hold in the 1980s. In the U.S., HIV was first discovered among gay men in California and New York.

In the early days of the epidemic, when the method of transmission was not yet known, many people ostracized those with HIV for fear they would contract the virus through proximity or physical contact. The discovery of the disease in gay and bisexual men, along with the revelation that the virus could be passed by sharing needles used to inject drugs, led to intense discrimination, backlash, homophobia and stigmatization.

While improvements have been made in public awareness and perception of what it means to have HIV, remnants of discrimination and stigma still persist around the disease today.

How can you get HIV?

HIV can be spread through having anal, oral or vaginal sex with someone infected, coming in contact with infected blood through sharing needles or syringes (for drug use, tattoos, piercings, etc.), and by having the blood, semen or vaginal fluids of someone with HIV get into a sore, cut or open wound on your body.

It is possible for HIV to be spread from mother to child during pregnancy, childbirth or breastfeeding. Though rare in the U.S. because of screenings at blood banks, HIV can also be transmitted through blood transfusions that contain infected blood.

When left untreated, HIV can progress and develop into AIDS. People who have unprotected sex, have a sexually transmitted infection (STI) or use illicit injection drugs are at greater risk for contracting HIV.

Signs and symptoms

Signs and symptoms of HIV vary according to the stage of the infection. The three stages of HIV infection are primary infection or acute HIV, clinical latent infection or chronic HIV, and late-stage HIV or acquired immunodeficiency syndrome.

Acute HIV occurs within two to four weeks after contracting the virus and can cause a flu-like illness that may last for a few weeks.

Acute HIV may cause symptoms including:

  • Cough
  • Diarrhea
  • Fever
  • Headache
  • Joint pain and muscle aches
  • Painful sores in the mouth
  • Rashes
  • Sore throat
  • Swollen lymph nodes
  • Unintentional weight loss

During the chronic HIV stage, the virus is present in the body and in white blood cells. However, people often don't experience symptoms or infections during this stage, which can last for many years for anyone receiving antiretroviral therapy (ART). For others, this stage may last only a short time before the disease advances.

If symptoms occur during the chronic HIV stage, they can include:

  • Diarrhea
  • Fatigue
  • Fever
  • Oral yeast infection
  • Pneumonia
  • Shingles
  • Unintentional weight loss

Untreated HIV normally progresses to AIDS in a span of about eight to 10 years, according to Mayo Clinic. AIDS develops at a point when HIV has caused severe damage to the immune system, leaving the body extremely vulnerable to infections, opportunistic cancers and other diseases.

Fortunately, most people with HIV in the U.S. never develop AIDS thanks to access to modern antiviral treatments.

When a person has AIDS, symptoms can include:

  • Chronic diarrhea
  • Persistent fatigue
  • Rashes
  • Recurring fever
  • Sweats
  • Swollen lymph nodes
  • Unintentional weight loss
  • Weakness

Diagnosis and testing

If you think you may have been exposed to HIV or are at risk for contracting the virus, consult your doctor immediately. Detecting and treating the virus early is key to limiting its spread and achieving the best long-term health outlook.

HIV is diagnosed through the testing of blood or saliva. Some available tests include antigen, antibody and nucleic acid tests. Consult your doctor to determine which test is appropriate for you, as each has its own window to detect the virus based on time from exposure.

If the tests are negative but your doctor suspects you may have the virus, follow-up tests may be necessary weeks to months later to confirm whether you are infected or not. If you would rather test from home, at-home rapid tests and mail-in tests are available, too, though formal diagnosis can only be confirmed by a doctor.


There is currently no cure for HIV/AIDS. However, there are treatments that can effectively control HIV and avoid complications.

HIV and AIDS are treated with antiretroviral therapy. ART is used to treat the condition no matter what stage it's in or what complications are present. This treatment usually consists of a combination of medications from multiple drug classes, and typically can be combined and taken in a single daily pill. The treatment aims to lower the amount of HIV in the blood.

In many cases, the treatment allows individuals to achieve an undetectable viral load, most commonly known as undetectable equals untransmittable, or U=U, which means the level of infection in the blood is so low it cannot be transmitted.

Prevention and aftercare

Practicing safer sex, refraining from sharing needles with others and avoiding contact with blood and other bodily fluids of people who are infected reduce your risk of contracting HIV. People who are at risk for contracting HIV can take a medication called pre-exposure prophylaxis (PrEP) to protect themselves even more.

PrEP is a once-daily medication that decreases a person's chance of contracting HIV by blocking an HIV-specific enzyme so the virus cannot replicate adequately enough to survive in the body. The Centers for Disease Control and Prevention reports that PrEP is about 99 percent effective at preventing HIV transmission during sex and about 74 percent successful at blocking transmission during shared needle use. This makes PrEP an acceptable choice for partners of individuals with HIV or anyone who is at high risk for contracting the virus.

Living with HIV/AIDS can bring with it physical and mental challenges as well as assumptions and judgment from outsiders. Fortunately, treatment has made it possible to live a fulfilling life in all realms: family life, sex life, romance, business and friendships.

Still, living with a chronic illness can take a toll. Don't hesitate to reach out to a mental health professional and lean on your support system as you learn to navigate life with HIV/AIDS.

Clinical trials and research

Clinical trials are an essential part of furthering the advancement of medical research. They are commonly used to investigate potential cures, treatments and prevention methods for conditions such as HIV and AIDS.

In the event you might consider becoming a participant in any clinical trial, first do ample research and take time to make the decision in consultation with your primary care provider and loved ones. A list of active and recruiting clinical trials for various STDs/STIs can be found at the government database clinicaltrials.gov.

Resources for patients and caregivers

Education is power, and the more you know about this complex condition, the better prepared you'll be to conquer the effects and help others trying to lead healthy lives. Here are some good resources to begin your research:


What are the three stages of HIV/AIDS?

The three stages of HIV infection are primary infection or acute HIV, clinical latent infection or chronic HIV, and late-stage HIV or acquired immunodeficiency syndrome (AIDS).

How does HIV turn into AIDS?

HIV, when left untreated, typically advances to become AIDS in about eight to 10 years. AIDS develops when HIV has caused severe and permanent damage to the immune system, leaving the body particularly vulnerable to infections, opportunistic cancers and other diseases. Today, the vast majority of people with HIV in the U.S. never develop AIDS, thanks to access to modern antiviral treatments.

Can HIV/AIDS go away?

There is presently no cure for HIV/AIDS. However, there are treatments that can effectively control HIV and avoid complications. HIV and AIDS are treated with antiretroviral therapy (ART). ART is used to treat the condition no matter what stage it's in or what complications are present. The use of ART can potentially lead to U = U, or undetectable equals untransmittable, which means the level of infection in the blood is so low it cannot be transmitted.