Human immunodeficiency virus or HIV is a deadly virus that attacks the immune system of the body. This sexually transmitted disease (STD) interferes with the proper functioning of the immune system and makes the body more susceptible to a myriad of diseases. The body loses its ability to fight against disease causing viruses and bacteria and fall prey to infections like meningitis and pneumonia, and various types of cancer.
If HIV symptoms prolong and are left untreated, then they may cause AIDS (Acquired Immunodeficiency Syndrome), which is a fatal disease. A total of approximately 39.5 million people worldwide, have been affected by AIDS. Though in some countries, this deadly disease has seen a considerable decline, but in some countries the number of people affected has not changed and has even seen a growth.
HIV is often spread through sex with an infected person or through contact with contaminated blood, such as by sharing needles or syringes. Many people do not have symptoms when first infected with the virus, although some will have a flu-like illness within a month or two. Antiretroviral drugs can fight HIV infection, but they do not cure people of it or of AIDS.
AIDS (acquired immune deficiency syndrome) was first reported in the United States in 1981 and has since become a major worldwide epidemic. AIDS is caused by the human immunodeficiency virus (HIV). By killing or damaging cells of the body's immune system, HIV progressively destroys the body's ability to fight infections and certain cancers.
The term AIDS applies to the most advanced stages of HIV infection. More than 700,000 cases have been reported in the United States since 1981, and as many as 900,000 Americans may be infected with HIV. The epidemic is growing most rapidly among women and minority populations.
Scientists believe a virus similar to HIV first occurred in some populations of chimps and monkeys in Africa, where they're hunted for food. Contact with an infected monkey's blood during butchering or cooking may have allowed the virus to cross into humans and become HIV.
Infection with HIV occurs as a result of contact with bodily fluids like blood, semen, vaginal secretions, and breast milk. Saliva does not appear to carry HIV, although if there are wounds inside the mouth, the virus can be present the saliva. Once HIV enters the body, the retrovirus hijacks T-cells, forcing them to produce replications of HIV and transporting the virus throughout the body. Like other retroviruses, HIV carries its genetic material in RNA, rather than DNA.
By hijacking the T-cells, HIV makes these cells unavailable to the immune system. As a result, the virus weakens the immune system, putting the patient at risk of developing an opportunistic infection. If a patient infected with HIV develops an opportunistic infection, he or she is diagnosed with Acquired Immune Deficiency Syndrome. The difference between HIV and AIDS is that HIV is a virus, while AIDS is a collection of infections and symptoms caused by HIV infection.
HIV is spread most commonly by having sex (any type of sex, whether licit or illicit) with an infected person. HIV also is spread through contact with infected blood, which frequently occurs among injection drug users who share needles or syringes contaminated with blood from someone infected with the virus.
Women with HIV can transmit the virus to their babies during pregnancy, birth, or breastfeeding; however, if the mother takes the drug AZT during pregnancy, she can significantly reduce the chances that her baby will be infected with HIV.
A person can't become infected through ordinary contact — hugging, kissing, dancing or shaking hands — with someone who has HIV or AIDS. HIV can't be transmitted through the air, water or via insect bites.
Main article: HIV Symptoms
Many people do not develop any symptoms when they first become infected with HIV. Some people, however, have a flu-like illness within a month or two after exposure to the virus. More persistent or severe symptoms may not surface for a decade or more after HIV first enters the body in adults, or within two years in children born with HIV infection.
In many cases, early symptoms of HIV resemble a flu-like illness. However, in other cases, they may not appear at all. It often takes months to years before the signs and symptoms of HIV infection appear, but this varies from person to person. As the infection progresses, early symptoms of the infection can worsen to HIV symptoms such as weight loss, extreme fatigue, short-term memory loss, and more. This may include:
Fever
Headache
Tiredness
Enlarged lymph nodes (glands of the immune system easily felt in the neck and groin).
These HIV symptoms usually disappear within a week to a month, and are often mistaken for those of another viral infection. During this period, people are highly infectious (can easily spread the virus), and HIV is present in large quantities in genital fluids.
More persistent or severe symptoms of HIV may not appear for 10 years or more after HIV first enters the body in adults, or for 2 years in children born with HIV infection. This period of "asymptomatic" infection (without HIV symptoms) varies greatly in each individual. Some people may begin to have symptoms within a few months, while others may be symptom-free for more than 10 years.
Even during the asymptomatic period, the virus is actively multiplying, infecting, and killing cells of the immune system. The virus can also hide within infected cells and lie dormant. The most obvious effect of HIV infection is a decline in the number of CD4+ T cells found in the blood. These are the immune system's key infection fighters. The virus slowly disables or destroys these cells without causing symptoms.
As the immune system becomes weaker, a variety of complications start to take over. For many people, the first symptoms of HIV are large lymph nodes or "swollen glands" that may be enlarged for more than three months. Other symptoms of HIV often experienced months to years before the onset of AIDS include:
Lack of energy
Weight loss
Frequent fevers and sweats
Persistent or frequent yeast infections (oral or vaginal)
Persistent skin rashes or flaky skin
Pelvic inflammatory disease (in women) that does not respond to treatment
Short-term memory loss.
Some people with HIV symptoms develop frequent and severe herpes infections that cause mouth, genital, or anal sores, or a painful nerve disease called shingles. Children with symptoms may grow slowly or be sick a lot.
The term AIDS (acquired immune deficiency syndrome) applies to the most advanced stages of HIV infection. The definition of AIDS includes all HIV-infected people who have fewer than 200 CD4+ T cells per cubic millimeter of blood. (Healthy adults usually have CD4+ T-cell counts of 1,000 or more.)
HIV destroys CD4 cells — a specific type of white blood cell that plays a large role in helping your body fight disease. Your immune system weakens as more CD4 cells are killed. You can have an HIV infection for years before it progresses to AIDS.
To be diagnosed with AIDS, you must have a CD4 count under 200 or experience an AIDS-defining complication, such as:
Pneumocystis jiroveci pneumonia
Cytomegalovirus
Tuberculosis
Toxoplasmosis
Cryptosporidiosis
The definition of AIDS also includes 26 clinical conditions that affect people with advanced HIV disease. Most of these conditions are opportunistic infections that generally do not affect healthy people. In people with AIDS, these infections are often severe, and sometimes fatal, because the immune system is so ravaged HIV symptoms that the body cannot fight off certain bacteria, viruses, fungi, parasites, and other microbes.
Symptoms of opportunistic infections common in people with AIDS include:
Coughing and shortness of breath
Seizures and lack of coordination
Difficult or painful swallowing
Mental symptoms, such as confusion and forgetfulness
Severe and persistent diarrhea
Fever
Vision loss
Nausea, abdominal cramps, and vomiting
Weight loss and extreme fatigue
Severe headaches
Coma.
Children with AIDS may get the same opportunistic infections as do adults with the disease. In addition, they also have severe forms of the typically common childhood bacterial infections, such as conjunctivitis (pink eye), ear infections, and tonsillitis.
People with AIDS are also particularly prone to developing various cancers, especially those caused by viruses, such as:
Kaposi's sarcoma
Cervical cancer
Cancers of the immune system known as lymphomas.
These cancers are usually more aggressive and difficult to treat in people with AIDS. Signs of Kaposi's sarcoma in light-skinned people are round brown, reddish, or purple spots that develop in the skin or in the mouth. In dark-skinned people, the spots are more pigmented.
During the course of HIV infection, most people experience a gradual decline in the number of CD4+ T cells, although some may have abrupt and dramatic drops in their CD4+ T-cell counts. A person with CD4+ T cells above 200 may experience some of the early HIV symptoms. Others may have no symptoms even though their CD4+ T-cell count is below 200.
Many people are so debilitated by the symptoms of AIDS that they cannot hold a steady job or do household chores. Other people with AIDS may experience phases of intense life-threatening illness followed by phases in which they function normally.
A small number of people first infected with HIV 10 or more years ago have not developed symptoms of AIDS. Scientists are trying to determine what factors may account for their lack of progression to AIDS, such as:
Whether their immune systems have particular characteristics
Whether they were infected with a less aggressive strain of the virus
If their genes may protect them from the effects of HIV.
Scientists hope that understanding the body's natural method of controlling infection may lead to ideas for protective HIV vaccines and the use of vaccines to prevent the disease from progressing.
A variety of tests for HIV are available, such as urine tests, blood tests, oral tests, and others. They look for the presence of antibodies to HIV (proteins that fight the infection). Regardless of the type of test used, a positive test result must be confirmed with an additional specific test before a diagnosis of HIV can be given.
Several tests for HIV are available. These include:
Blood tests
Urine tests
Oral tests
Rapid tests
Home tests.
When HIV enters the body, it begins to attack certain white blood cells called T4 lymphocyte cells (helper cells). Your doctor may also call them CD4 cells. The immune system then produces antibodies to fight off the infection. Thus, the presence of HIV antibodies results from being infected with HIV. Although these antibodies are ineffective at destroying HIV, their presence is used to confirm an infection. HIV tests look for the presence of HIV antibodies; they do not test for the virus itself.
Several blood-based HIV tests are available:
ELISA or EIA for initial screening
Western blot to confirm the diagnosis
Other, newer blood tests.
Screening Tests: ELISA or EIA HIV
HIV testing consists of an initial screening with two types of blood tests commonly used to detect an infection. The most commonly used initial blood test is an enzyme immune assay (EIA) or the enzyme-linked immunosorbent assay (ELISA) test. If EIA test results show a reaction, the test is repeated on the same blood sample.
Confirmation Tests
If the sample repeatedly shows the same result or either duplicate test is reactive, the results are "confirmed" using a second HIV blood test, such as the Western blot. This more specific (and more expensive) test can tell the difference between HIV antibodies and other antibodies that can react to the EIA and cause false-positive results. False-positive EIA results are uncommon, but can occur. A person is considered infected following a repeatedly reactive result from the EIA, confirmed by the Western blot test.
New HIV Blood Tests
In addition to the EIA or ELISA and Western blot, other blood tests for HIV now available include:
Radioimmunoprecipitation assay (RIPA): A confirmatory blood test that may be used when antibody levels are very low or difficult to detect, or when Western blot test results are uncertain. An expensive test, the RIPA requires time and expertise to perform.
Dot-blot immunobinding assay: A rapid-screening blood test that is cost-effective and that may become an alternative to standard EIA and Western blot testing.
Immunofluorescence assay: A less commonly used confirmatory blood test for HIV used on reactive ELISA samples or when Western blot test results are uncertain.
Nucleic acid testing: For example, viral RNA or proviral DNA amplification method. A less available blood test that can be used to resolve an initial indeterminate Western blot result in certain situations.
Polymerase chain reaction (PCR): A specialized blood test that looks for HIV genetic information. Although expensive and labor-intensive, the test can detect the virus even in someone only recently infected.
Urine and oral tests for HIV offer alternatives for anyone reluctant to have their blood drawn.
Urine Test
A urine HIV test is not as sensitive or specific as blood testing. Available urine tests include an EIA and a Western blot test that can confirm EIA results. A physician must order these tests, and the results are reported to the ordering physician or his or her assistant.
Oral Test
Orasure and OraQuick Advance HIV-1/2 are currently the only oral-fluid tests approved by the U.S. Food and Drug Administration (FDA). Fluid is collected from inside the mouth and analyzed using an EIA test and supplemental Western blot test, if necessary. Oral fluid tests are offered at many HIV testing locations. Contact a location near you to find out if this test is available.
A rapid test usually produces results in up to 20 minutes. In comparison, results from the commonly used HIV-antibody screening test, the EIA, are not available for one to two weeks. There are currently four rapid HIV tests licensed for use in the United States:
OraQuick Rapid HIV-1 and Advance HIV-1/2 Antibody Tests, manufactured by OraSure Technologies, Inc.
Reveal G2 HIV-Antibody Tests, manufactured by MedMira, Inc.
Multispot, manufactured by Bio-Rad Laboratories
Uni-Gold Recombigen, manufactured by Trinity Biotech.
The availability of these tests may differ from one place to another. These rapid tests are considered just as accurate as the EIA. As is true for all screening tests (including the EIA), a positive test result must be confirmed with an additional specific test before a diagnosis of HIV infection can be given.
The FDA has not approved any home-use HIV test kits, which allow consumers to interpret their own results in a few minutes. The Federal Trade Commission (FTC) has warned that these home-use test kits, many of which are available on the Internet, supply inaccurate results.
Currently, only the Home Access test is approved by the FDA. The Home Access test kit can be found at most drugstores. The testing procedure involves pricking your finger, placing drops of blood on a specially treated card, and then mailing the card in for testing at a licensed laboratory. Customers are given an identification number to use when phoning for the test results. Callers may speak to a counselor before taking the test, while waiting for the test result, and when getting the result.
There is no cure for HIV, but treatments are much more successful than they used to be, enabling people with the virus to stay healthy and live longer.
If you think you have been exposed to the virus within the last 72 hours (three days), anti-HIV medication may stop you becoming infected.
For it to be effective, the medication, called post-exposure prophylaxis or PEP, must be started within 72 hours of coming into contact with the virus.
The quicker PEP is started the better, ideally within hours of coming into contact with HIV. The longer the wait, the less chance of it being effective.
PEP is a month-long treatment, which has serious side effects and is not guaranteed to work. The treatment involves taking the same drugs prescribed to people who have tested positive for HIV.
You may be able to get PEP from:
sexual health clinics, or genitourinary medicine (GUM) clinics
hospitals (usually A&E or accident and emergency departments)
if you already have HIV, try your HIV clinic if the PEP is for someone you've had sex with
Not all these places in every part of the country will have PEP or be able to give it. Doctors usually do not provide PEP.
If you are diagnosed with HIV, you will have regular blood tests to monitor the progress of the virus before starting treatment.
You will not normally need to start treatment until the virus has begun weakening your immune system.
This is determined by mainly by measuring your levels of CD4, which are infection-fighting cells, in your blood.
Treatment is usually recommended to begin when your CD4 count falls below 350, whether or not you have any symptoms.
The aim of the treatment is to reduce the level of HIV in the blood and prevent or delay any HIV-related illnesses.
HIV is treated with antiretrovirals (ARVs), which work against the HIV infection by slowing down the spread of the virus in the body.
Patients tend to take three or more types of ARV medication. This is known as combination therapy or highly active antiretroviral therapy (HAART).
A combination of ARVs is used because HIV can quickly adapt and become resistant to one single ARV.
Different combinations of ARVs work for different people so the medicine you take will be individual to you.
Once HIV treatment is started, you will probably need to take the medication for the rest of your life. For the treatment to be effective, it will need to be taken on time, every time.
Many of the medicines used to treat HIV can react in unpredictable ways if you take them with other types of medicines.
These include herbal remedies such as St John's Wort, drugs such as cocaine, and some over-the-counter medicines. Always check with clinic staff or your doctor before taking any other medicines.
Other classes of anti-HIV drugs include:
Non-nucleoside reverse transcriptase inhibitors (NNRTIs). NNRTIs disable a protein needed by HIV to make copies of itself. Examples include efavirenz (Sustiva), etravirine (Intelence) and nevirapine (Viramune).
Nucleoside reverse transcriptase inhibitors (NRTIs). NRTIs are faulty versions of building blocks that HIV needs to make copies of itself. Examples include Abacavir (Ziagen), and the combination drugs emtricitabine and tenofovir (Truvada), and lamivudine and zidovudine (Combivir).
Protease inhibitors (PIs). PIs disable protease, another protein that HIV needs to make copies of itself. Examples include atazanavir (Reyataz), darunavir (Prezista), fosamprenavir (Lexiva) and ritonavir (Norvir).
Entry or fusion inhibitors. These drugs block HIV's entry into CD4 cells. Examples include enfuvirtide (Fuzeon) and maraviroc (Selzentry).
Integrase inhibitors. Raltegravir (Isentress) works by disabling integrase, a protein that HIV uses to insert its genetic material into CD4 cells.
ARV treatment is available to prevent a pregnant woman from passing HIV to her child.
Without treatment, there is a one in four chance that your baby will develop HIV. With treatment, the risk is less than one in a hundred.
Advances in treatment mean there is no increased risk of passing the virus to your baby with a normal delivery. However, for some women, a caesarean section may still be recommended.
If you have HIV, do not breastfeed your baby because the virus can be transmitted through breast milk.
HIV treatment only works if you take your pills on time, every time. Missing even a few doses will increase the risk of your treatment not working.
You will need to develop a daily routine to fit your treatment plan around your lifestyle.
Current guidelines indicate that treatment should begin if:
You have severe symptoms
Your CD4 count is under 500
You're pregnant
You have HIV-related kidney disease
You're being treated for hepatitis B
HIV treatment regimens may involve taking multiple pills at specific times every day for the rest of your life. HIV treatment can have unpleasant side effects. If you get serious side effects (which is uncommon) you may need to try a different combination of ARVs.
Side effects can include:
Nausea, vomiting or diarrhea
Abnormal heartbeats
Shortness of breath
Skin rash
Weakened bones
Bone death, particularly in the hip joints
Tiredness
Mood changes
Gaining fat on one part of your body while losing it on another
People with HIV can get treated by their own doctor or by a specialist at an HIV clinic or a GUM clinic.
Services, including support organizations, may work together to provide specialist care and emotional support.
Your response to any treatment is measured by your viral load and CD4 counts. Viral load should be tested at the start of treatment and then every three to four months while you're undergoing therapy. CD4 counts should be checked every three to six months.
HIV treatment should reduce your viral load to the point that it's undetectable. That doesn't mean your HIV is gone. It just means that the test is not sensitive enough to detect it. You can still transmit HIV to others when your viral load is undetectable.
Although it's important to receive medical treatment for HIV/AIDS, it's also essential to take an active role in your own care. The following suggestions may help you stay healthy longer:
Eat healthy foods. Emphasize fresh fruits and vegetables, whole grains and lean protein. Healthy foods help keep you strong, give you more energy and support your immune system.
Avoid certain foods. Food-borne illnesses can be especially severe in people who are infected with HIV. Avoid unpasteurized dairy products, raw eggs and raw seafood such as oysters, sushi or sashimi. Cook meat until it's well-done or until there's no trace of pink color.
Get immunizations. These may prevent infections such as pneumonia and the flu. Make sure the vaccines don't contain live viruses, which can be dangerous for people with weakened immune systems.
Take care with companion animals. Some animals may carry parasites that can cause infections in people who are HIV-positive. Cat feces can cause toxoplasmosis, while pet reptiles can carry salmonella.
People who are infected with HIV sometimes try dietary supplements that claim to boost the immune system or counteract side effects of anti-HIV drugs.
Supplements that may be helpful
Fish oil. Some anti-HIV drugs can cause increases in cholesterol levels. Studies indicate that fish oil supplements can help bring those numbers down.
Whey protein. Preliminary evidence indicates that whey protein, a cheese by-product, can help some people with HIV gain weight. Whey protein also appears to reduce diarrhea and increase CD4 counts.
Coenzyme Q10. This supplement appears to increase levels of CD4 cells, which could make your immune system stronger. More research is needed, however.
Supplements that may be dangerous
St. John's wort. Commonly used to combat depression, St. John's wort can reduce the effectiveness of several types of anti-HIV drugs by more than 50 percent.
Garlic supplements. Although garlic may help strengthen the immune system, it also interacts with several anti-HIV drugs — reducing their effectiveness by 50 percent. Occasionally eating garlic in food appears to be safe.