HIV and AIDS Facts

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What is HIV/AIDS?

HIV (human immunodeficiency virus) is a virus that attacks the immune system and—left untreated—causes AIDS (acquired immune deficiency syndrome).

Key HIV/AIDS facts include:

  • HIV is spread through sexual contact, contaminated blood and needles, and from an infected mother to her baby.

  • HIV infection is a chronic, lifelong condition. The human body cannot clear HIV like it does many other viruses.

  • The main difference between HIV vs. AIDS is HIV is an infectious disease, and AIDS is an irreversible immune system disorder caused by HIV.

  • Early symptoms of HIV/AIDS, if present, resemble flu symptoms, such as fatigue, headache, fever, and swollen glands, which may start 1 to 2 months after infection then disappear.

  • AIDS, which can develop as many as 10 years after HIV infection, is characterized by persistent and more severe symptoms and such conditions as herpes, tuberculosis, pneumonia, encephalitis, certain cancers, and neurologic problems.

  • Left untreated, HIV/AIDS is fatal for 90% of those infected.

  • There is not yet a cure or vaccine for HIV/AIDS, but early HIV diagnosis and treatment can slow the disease. Effective HIV treatment can greatly delay and even prevent AIDS, improve quality of life, and help prevent the spread of HIV.

What are the different stages of HIV/AIDS?

Without treatment, HIV infection progresses in stages:

  • Stage 1, acute HIV infection: People are very contagious at this stage, when there are large amounts of virus in the bloodstream. Some people develop flu-like symptoms within 2 to 4 weeks after infection.

  • Stage 2, clinical latency or HIV dormancy: HIV is still replicating, but at very low levels compared to stage 1. Without treatment, stage 2 can last a decade or longer. With treatment, stage 2 can last for several decades or be lifelong.

  • Stage 3, AIDS: HIV has damaged the immune system to such a degree it can no longer protect the body from infection and disease. Stage 3 survival is about 3 years. People with AIDS may have a high viral load and are very infectious.


Who gets HIV/AIDS?

HIV/AIDS statistics from published data include these U.S. facts:

  • About 38,000 people a year receive an HIV diagnosis, based on data from 2017 and the last several years.

  • 1.2 million people are living with HIV infection, but 13% are unaware they are infected  (based on modeling).

  • Most new HIV cases are in people ages 25 to 34.

  • Gay and bisexual men account for about 66% of new cases.

  • In 2017, among gay and bisexual men with HIV, African Americans represented about 38% of cases, Hispanic Americans 29%, and White Americans 28%.

  • Since 2012, the rate among Hispanic gay and bisexual men has increased 12% and the rate among white gay and bisexual men has decreased 14%. (Rates of African American gay and bisexual male cases have remained stable.)

  • In 2017, heterosexuals accounted for 24% of all HIV diagnoses, with the virus more predominantly affecting heterosexual women (16% of all cases) than heterosexual men (7% of all cases).

  • Among women with HIV from heterosexual contact, African Americans represented 66% of cases, Hispanic Americans 17.4%, and White Americans 16.5%.

  • People with other sexually transmitted diseases have a greater risk of contracting or spreading HIV.

Can you die of HIV/AIDS?

HIV/AIDS life expectancy and prognosis depends on many different factors, but prognosis is generally very good with early diagnosis and effective treatment. A 10-year study from the U.K. showed that patients who had a good response to modern HIV therapies had a normal, if not better, life expectancy than average.

Annually, for the past 5 years, approximately 13,000 to 16,000 people with HIV/AIDS have died, due to any cause.  Contrast this data to the early 1990s, when more than 50,000 people a year died with the disease. Deaths have declined sharply since the mid-1990s, with introduction of anti-HIV therapies.

Left untreated, HIV/AIDS prognosis is poor and eventually fatal for most people.

How does HIV/AIDS affect quality of life?

Numerous studies on the quality of life and health-related quality of life (HRQoL) of people living with HIV show that they have a lower quality of life compared to the general population. HRQoL studies show the effect of treatment and the patient’s physical, mental, and social health on the quality of life. Many factors influence quality of life for people with HIV, including time since diagnosis. Some studies show HRQoL is better for more recently diagnosed patients compared to patients diagnosed closer to the start of the epidemic.

Overall, issues that lower a patient’s HRQoL include:   

  • HIV symptoms

  • Progression to AIDS

  • Treatment side effects and difficulty with medication regimen

  • Lack of social support

  • Experiencing anti-HIV/AIDS stigma

  • Low energy level, fatigue

  • Poor coping skills

  • Presence of mental health disorder

  • Memory and thinking problems

Factors that raise HRQoL include:

  • Employment and higher income and education level

  • Younger age

  • Stable relationship and good social support

  • Treatment success (with manageable side effects)

  • Good communication with healthcare providers

What causes HIV/AIDS?

Human immunodeficiency virus infects and reproduces in specific immune cells—mainly T-cells bearing the CD4 receptor on their surface. HIV disables and depletes CD4 cells from the immune system, which makes it hard for the body to fight off infections and some forms of cancer. As the immune system deteriorates with time, complications begin to surface, leading to AIDS.

A person’s genetic makeup can also play a role in HIV/AIDS. Scientists have discovered certain variations in HLA genes and other genes that affect a person’s susceptibility or resistance to HIV. Genetic research has even led to a new class of anti-HIV drugs.

How does HIV spread?

Infected blood, semen, pre-seminal fluid, rectal fluid, vaginal fluid, and breast milk can transmit the virus to mucous membranes or broken tissue upon direct contact. (The mouth, vagina, rectum and penis have mucous membranes.) In the United States, HIV is mainly spread through anal or vaginal sex and needle or syringe use.

It is less common for HIV to spread from being stuck by an infected needle or from an infected mother to her child (during pregnancy, childbirth or breastfeeding).

It is extremely rare for HIV to spread via oral sex, blood transfusions, or contact with infected blood from broken skin or wounds.

HIV is NOT spread by biting insects, sweat, saliva, or sharing food, drinks or toilets.

How are you diagnosed with HIV/AIDS?

HIV infection is diagnosed with tests that detect viral antigens or viral antibodies, or both, in a sample of blood or oral fluid. Most diagnostic and screening HIV tests are combined antigen/antibody tests. Home testing and rapid-result kits are typically antibody tests. A clinic needs to confirm rapid and home test results.

Another test—the nucleic acid test (NAT), or HIV viral load test—directly measures the amount of HIV in a blood sample. It is useful when measuring the effect of treatment and when a person is highly likely to be infected with HIV and yet antigen/antibody tests are negative.

An HIV-positive patient receives an AIDS diagnosis if they develop an increasing number of so-called opportunistic infections. These illnesses are more common in people with suppressed immune systems, including HIV patients, because the immune system can no longer fight off disease. A CD4 cell count of less than 200 cells/mm3 also indicates HIV has turned into AIDS. The CD4 cell count of a healthy person who does not have HIV is 500 to 1500 cells/mm3.

What are common treatments for HIV/AIDS?

Medication is the only way to treat HIV infection and delay or prevent AIDS. Since HIV is a retrovirus, medications that inhibit HIV are known as antiretroviral drugs.

Forms of HIV/AIDS treatments include:

  • ART (antiretroviral therapy): A combination of antiretroviral drugs that blocks HIV from producing more virus, which reduces viral load and prevents or delays AIDS. ART also reduces the risk of spreading the virus.

  • PrEP (pre-exposure prophylaxis): Two antiretroviral drugs in a pill (brand name Truvada) taken daily by people at high risk for contracting HIV. When combined with safe-sex practices PrEP greatly reduces the risk of HIV infection.

  • PEP (post-exposure prophylaxis): An emergency dose of antiretrovirals taken within 72 hours after potential or known HIV exposure, such as through unprotected sex or sharing needles. One of the drugs can cause birth defects, so doctors prescribe other drugs to pregnant women early in pregnancy and to women of childbearing age not on birth control.

Additional HIV/AIDS facts

HIV/AIDS remains a significant public health problem in the United States and globally. Many U.S. efforts to control HIV/AIDS focus on sexual health awareness and HIV testing and prevention—particularly among adolescents and young adults. Learn more at the National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention.

December is HIV/AIDS awareness month, and World AIDS Day is December 1.

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Medical Reviewer: William C. Lloyd III, MD, FACS
Last Review Date: 2019 Jan 11
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  9. Duracinsky M, Herrmann S, Berzins B, et al. The development of PROQOL-HIV: an international instrument to assess the health-related quality of life of persons living with HIV/AIDS. J Acquir Immune Defic Syndr. 2012;59(5):498-505.
  10. Miners A, Phillips A, Kreif N, et al. Health-related quality-of-life of people with HIV in the era of combination antiretroviral treatment: a cross-sectional comparison with the general population. Lancet HIV. 2014;1(1):e32-40.
  11. Degroote S, Vogelaers D, Vandijck DM. What determines health-related quality of life among people living with HIV: an updated review of the literature. Arch Public Health. 2014;72(1):40.

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