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.

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)

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:

• Thrush (an overgrowth of yeast)
• Pneumonia (particularly Pneumocystis jiroveci pneumonia)
• Invasive fungal infections (resulting in brain and/or lung infections)
• Toxoplasmosis infection
• Tuberculosis
• Viral brain infection
• Kaposi's sarcoma
• Lymphoma
• Cervical cancer
• Eye disease due to cytomegalovirus infection
• Intestinal infections, especially due to shigella, salmonella , and campylobacter
• Severe weight loss (wasting syndrome)
• Severe skin rashes
• Reactions to medications
• Psychiatric problems, including depression and dementia

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.

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. *²

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)

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

• Pneumonia
• Thrush
• Repeated herpes infections
• Toxoplasma brain infections