Acquired Immunodeficiency Syndrome and Human Immunodeficiency Virus
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Acquired Immunodeficiency Syndrome and Human Immunodeficiency Virus

(AIDS and HIV)

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Acquired immunodeficiency syndrome (AIDS) is an illness that weakens the body's immune system. The immune systems of people with AIDS are not able to fight off certain infections and cancers.


AIDS is caused by the human immunodeficiency virus (HIV), which destroys important immune system cells. HIV is spread through contact with HIV-infected blood or other body fluids including semen, vaginal fluid, and breast milk.

Immune System

Immune system white blood cell

HIV destroys white blood cells vital to the immune system.

© 2008 Nucleus Medical Art, Inc.

HIV is spread through:

  • Sexual contact with an HIV-infected person, especially intercourse or anal sex
  • Transfer of HIV from a mother to child during pregnancy, childbirth, or breastfeeding
  • Being pricked by an HIV-contaminated needle
  • Having a blood transfusion with HIV-infected blood (rare today, due to testing of all donated blood for HIV infection beginning in 1985)

Rarely, HIV can be spread through:

  • Blood from an HIV-infected person getting into an open wound of another person
  • Being bitten by someone infected with HIV
  • Sharing personal hygiene items with an HIV-infected person (razors, toothbrushes, etc)

Risk Factors

A risk factor is something that increases your chance of getting a disease or condition.

Risk factors include:

  • Having multiple sexual partners
  • Sharing needles for injecting drugs
  • Having regular exposure to HIV-contaminated blood or other body fluids (a concern for healthcare workers)
  • Being born to an HIV-infected mother
  • Receiving donor blood products, tissue, organs, or artificial insemination
  • Being an immigrants from geographic locations with high numbers of AIDS patients (east central Africa and Haiti)
  • Having a sexual relationship with a high-risk individual or a partner already infected with HIV


HIV may not cause symptoms for a number of years.

Early symptoms that you may experience a month or two after becoming infected may last a couple of weeks. These include:

  • Rapid weight loss
  • Dry cough
  • Sore throat
  • Recurring fever
  • Night sweats
  • Extreme, unexplained fatigue
  • Swollen lymph nodes in armpits, neck, or groin
  • White spots on the tongue or in the mouth or throat
  • Headache
  • Discomfort from light
  • Rash
  • Depression
  • Irritable mood
  • Memory loss or other neurological disorder

After these initial symptoms are gone, there may be no symptoms for months to years. Then, the following symptoms may occur over the course of 1 to 3 years:

  • Swollen lymph glands all over the body
  • Fungal infections of the mouth, fingernails, toes
  • Repeated vaginal infections (yeast and Trichomonas)
  • Development of lots of warts
  • Exacerbations of prior conditions, such as eczema, psoriasis, herpes infection
  • Shingles
  • Night sweats
  • Weight loss
  • Chronic diarrhea

Once HIV has progressed to AIDS, the immune system has become quite weakened. Opportunistic infections are will occur. These are infections that people with a normal immune system don't usually get. The infections occur in patients with AIDS because of the weakened immune system. Examples of opportunistic infections and other complications of AIDS include:


The doctor will ask about your symptoms, medical history, and risk factors. A physical exam will be done.

A blood test called an ELISA test is used to detect HIV infection. If an ELISA test is positive, the Western blot blood test is usually done to confirm the diagnosis. The ELISA test may be negative if you were infected with HIV recently.

Many people (95%) will have a positive test within three months. Most people (99%) will have a positive test within six months. If an ELISA test is negative, but you think you may have HIV, you should be tested again in 1 to 3 months.


Medications can prevent, delay, or control the development of AIDS in many people infected with HIV.

Drugs That Fight HIV

These drugs are often given in combination, referred to popularly as AIDS cocktails. They include:

Nucleoside reverse transcriptase inhibitors:

  • AZT (Zidovudine or ZDV)
  • ddC (Zalcitabine)
  • ddI (dideoxyinosine)
  • d4T (Stavudine)
  • 3TC (Lamivudine)
  • Emtricitabine (Emtriva)
  • Abacavir (Ziagen)
    • In some patients, abacavir can cause a hypersensitivity reaction, which can be life-threatening. Researchers found that screening for a particular gene can help to prevent this reaction.

Nucleotide reverse transcriptase inhibitors:

  • Delavirdine (Rescriptor)
  • Nevirapine (Viramune)
  • Efavirenz (Sustiva)

Protease inhibitors:

  • Ritonavir (Norvir)
  • Saquinavir (Invirase)
  • Indinavir (Crixivan)
  • Amprenavir (Agenerase)
  • Nelfinavir (Viracept)
  • Lopinavir (Kaletra)
  • Atazanavir (Reyataz)
  • Tipranavir (Aptivus)
  • Darunavir (Prezista)

Combination pill:

  • Atripla (Efavirenz, Tenofovir and Emtricitabine)
  • Enfuvirtide (Fuzeon)
  • Raltegravir (Isentress)
  • Maraviroc (Selzentry)

Drugs That Fight AIDS-Related Infections and Cancers

People who have developed AIDS are treated with numerous drugs that help prevent:


To prevent becoming infected with HIV:

  • Abstain from sex or use a male latex condom (includes intercourse and any other sexual acts that result in the exchange of bodily fluids).
  • Do not share needles for drug injection.
  • Limit your number of sexual partners.
  • Avoid sexual partners who are HIV-infected or injection drug users.
  • Avoid receiving transfusion of unscreened blood products.
  • If you are a healthcare worker:
    • Wear latex gloves and facial masks during all procedures.
    • Carefully handle and properly dispose of needles.
    • Carefully follow universal precautions (a detailed list of how to handle such things as needles and other biohazard materials).
  • If you live in a household with an HIV-infected person:
    • Wear latex gloves if handling HIV-infected bodily fluids.
    • Cover all cuts and sores, yours and the HIV-infected person's with bandages.
    • Do not share any personal hygiene items such as razors, toothbrushes, etc.
    • Carefully handle and properly dispose of needles used for medication.

Three recent trials involving over 11,000 Africans found that circumcised men were significantly less likely to develop HIV infection compared to uncircumcised men. In the US, most men are already circumcised and the risk of HIV is far lower. It is still important to consider that circumcision can apparently reduce the risk of HIV transmission.

To prevent spreading HIV to others if you are HIV infected:

  • Abstain from sex or use a male latex condom (includes intercourse and any other sexual acts that result in the exchange of bodily fluids).
  • Inform former or potential sexual partners.
  • Do not donate blood or organs.
  • Try not to get pregnant. Ask your doctor about contraception.
  • If you have a baby, do not breastfeed.


American Foundation for AIDS Research

Centers for Disease Control and Prevention


AIDS Committee of Toronto

Canadian AIDS Society


Adult male circumcision significantly reduces risk of acquiring HIV [press release]. National Institutes of Health website. Available at: Accessed June 13, 2008.

Berkow R. The Merck Manual of Medical Information. New York, NY: Simon and Schuster, Inc.; 2000.

HIV/AIDS A-Z index. Centers for Disease Control and Prevention website. Available at: Accessed June 13, 2008.

National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention.Centers for Disease Control and Prevention website. Available at: Accessed June 13, 2008.

Rey D, Krebs M, Partisani M, Hess G, et al. Virologic response of zidovudine, lamivudine, and tenofovir disoproxil fumarate combination in antiretroviral-naive HIV-1-infected patients. J Acquir Immune Defic Syndr. 2006;43: 530-534.

Ross LL, Parkin N, Gerondelis P, et al. Differential impact of thymidine analogue mutations on emtricitabine and lamivudine susceptibility. J Acquir Immune Defic Syndr. 2006;43(5):567-570.

*¹3/8/2007 DynaMed's Systematic Literature Surveillance DynaMed's Systematic Literature Surveillance: Auvert B, Taljaard D, Lagard E, Sobngwi-Tambekou J, Sitta R, Puren A. Randomized, controlled intervention trial of male circumcision for reduction of HIV infection risk: the ANRS 1265 Trial. PLoS Med. 2005;2(11):e298. Epub Oct 25, 2005.
Bailey RC, Moses S, Parker CB, et al. Male circumcision for HIV prevention in young men in Kisumu, Kenya: a randomised controlled trial. Lancet. 2007 Feb 24;369(9562):643-656.
Gray RH, Kigozi G, Serwadda D, et al. Male circumcision for HIV prevention in men in Rakai, Uganda: a randomised trial. Lancet. 2007 Feb 24;369(9562):657-666.

*²2/21/2008 DynaMed's Systematic Literature Surveillance DynaMed's Systematic Literature Surveillance: Mallal S, Phillips E, Carosi G, et al. HLA-B*5701 screening for hypersensitivity to abacavir. N Engl J Med. 2008;358:568-579.

Last reviewed December 2007 by David L. Horn, MD, FACP

Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.

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