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Human Immunodeficiency Virus (HIV) Infection

Topic Overview

What is HIV? What is AIDS?

HIV (human immunodeficiency virus) is a virus that attacks the immune system, the body's natural defense system. Without a strong immune system, the body has trouble fighting off disease. Both the virus and the infection it causes are called HIV.

White blood cells are an important part of the immune system. HIV infects and destroys certain white blood cells called CD4+ cells. If too many CD4+ cells are destroyed, the body can no longer defend itself against infection.

The last stage of HIV infection is AIDS (acquired immunodeficiency syndrome). People with AIDS have a low number of CD4+ cells and get infections or cancers that rarely occur in healthy people. These can be deadly.

But having HIV does not mean you have AIDS. Even without treatment, it takes a long time for HIV to progress to AIDS—usually 10 to 12 years. When HIV is diagnosed before it becomes AIDS, medicines can slow or stop the damage to the immune system. If AIDS does develop, medicines can often help the immune system return to a healthier state. With treatment, many people with HIV are able to live long and active lives.

What causes HIV?

HIV infection is caused by the human immunodeficiency virus. You can get HIV from contact with infected blood, semen, or vaginal fluids.

  • Most people get the virus by having unprotected sex with someone who has HIV.
  • Another common way of getting the virus is by sharing drug needles with someone who is infected with HIV.
  • The virus can also be passed from a mother to her baby during pregnancy, birth, or breast-feeding.

HIV doesn't survive well outside the body. So it cannot be spread by casual contact such as kissing or sharing drinking glasses with an infected person.

What are the symptoms?

HIV may not cause symptoms early on. People who do have symptoms may mistake them for the flu or mono. Common early symptoms include:

  • Fever.
  • Sore throat.
  • Headache.
  • Muscle aches and joint pain.
  • Swollen glands (swollen lymph nodes).
  • Skin rash.

Symptoms may appear from a few days to several weeks after a person is first infected. The early symptoms usually go away within 2 to 3 weeks.

After the early symptoms go away, an infected person may not have symptoms again for many years. Without treatment, the virus continues to grow in the body and attack the immune system. After a certain point, symptoms reappear and then remain. These symptoms usually include:

  • Swollen lymph nodes.
  • Extreme tiredness.
  • Weight loss.
  • Fever.
  • Night sweats.

A doctor may suspect HIV if these symptoms last and no other cause can be found.

Treatment usually keeps the virus under control and helps the immune system stay healthy.

How is HIV diagnosed?

The U.S. Food and Drug Administration (FDA) has approved tests that detect HIV antibodies in urine, fluid from the mouth (oral fluid), or blood. If a test on urine or oral fluid shows that you are infected with HIV, you will probably need a blood test to confirm the results. If you have been exposed to HIV, your immune system will make antibodies to try to destroy the virus. Blood tests can find these antibodies in your blood.

Most doctors use two blood tests, called the ELISA and the Western blot assay. If the first ELISA is positive (meaning that HIV antibodies are found), the blood sample is tested again. If the second test is positive, a Western blot will be done to be sure.

It may take as long as 6 months for HIV antibodies to show up in a blood sample. If you think you have been exposed to HIV but you test negative for it:

  • Get tested again. Tests at 6, 12, and 24 weeks can be done to be sure you are not infected.
  • Meanwhile, take steps to prevent the spread of the virus. If you are infected, you can still pass HIV to another person during this time.

Some people are afraid to be tested for HIV. But if there is any chance you could be infected, it is very important to find out. HIV can be treated. Getting early treatment can slow down the virus and help you stay healthy. And you need to know if you are infected so you can prevent spreading the infection to other people.

You can get HIV testing in most doctors' offices, public health clinics, hospitals, and Planned Parenthood clinics. You can also buy a home HIV test kit in a drugstore or by mail order. But be very careful to choose only a test that has been approved by the FDA. If a home test is positive, see a doctor to have the result confirmed and to find out what to do next.

How is it treated?

The standard treatment for HIV is a combination of medicines called highly active antiretroviral therapy (HAART). Antiretroviral medicines slow the rate at which the virus multiplies. Taking these medicines can reduce the amount of virus in your body and help you stay healthy.

The U.S. National Institutes of Health (NIH) recommends that people begin treatment for HIV as soon as they know that they are infected.1

To monitor the HIV infection and its effect on your immune system, a doctor will do two tests:

  • Viral load, which shows the amount of virus in your blood
  • CD4+ cell count, which shows how well your immune system is working

Your doctor will repeat the tests on a regular basis to see how you are doing.

After you start treatment, it is important to take your medicines exactly as directed by your doctor. When treatment doesn't work, it is often because HIV has become resistant to the medicine. This can happen if you don't take your medicines correctly. Ask your doctor if you have questions about your treatment.

Treatment has become much easier to follow over the past few years. New combination medicines include two or three different medicines in one pill. Many people with HIV get the treatment they need by taking just one or two pills a day.

To stay as healthy as possible during treatment:

  • Don't smoke. People with HIV are more likely to have a heart attack or get lung cancer.2, 3 Smoking can increase these risks even more.
  • Eat a healthy, balanced diet to keep your immune system strong.
  • Get regular exercise to reduce stress and improve the quality of your life.
  • Don't use illegal drugs, and limit your use of alcohol.

Learn all you can about HIV so you can take an active role in your treatment. Your doctor can help you understand HIV and how best to treat it. Also, consider joining an HIV support group. Support groups can be a great place to share information and emotions about HIV infection.

How can you prevent HIV?

HIV can be spread by people whether they know they are infected or not. To protect yourself and others:

  • Practice safe sex. Use a condom every time you have sex (including oral sex) until you are sure you and your partner are not infected with HIV or other sexually transmitted infection (STI).
  • Don't have more than one sex partner at a time. The safest sex is with one partner who has sex only with you.
  • Talk to your partner before you have sex the first time. Find out if he or she is at risk for HIV. Get tested together. Getting tested again at 6, 12, and 24 weeks after the first test can be done to be sure neither of you is infected. Use condoms in the meantime.
  • Don't drink a lot of alcohol or use illegal drugs before sex. You might let down your guard and not practice safe sex.
  • Don't share personal items, such as toothbrushes or razors.
  • Never share needles or syringes with anyone.

Frequently Asked Questions

Learning about HIV:

Being diagnosed:

Getting treatment:

Living with HIV:

Health Tools Health Tools help you make wise health decisions or take action to improve your health.

Health Tools help you make wise health decisions or take action to improve your health.
Decision Points focus on key medical care decisions that are important to many health problems. Decision Points focus on key medical care decisions that are important to many health problems.
  HIV: When Should I Start Taking Antiretroviral Medicines for HIV Infection?


Actionsets help people take an active role in managing a health condition. Actionsets are designed to help people take an active role in managing a health condition.
  HIV: Taking Antiretroviral Drugs

Cause

The infection is caused by the human immunodeficiency virus (HIV).

After HIV is in the body, it infects and destroys CD4+ cells, which are the part of the body's immune system that fights infection and disease. When HIV weakens or destroys the immune cells, it may lead to certain illnesses or diseases, such as some types of pneumonia or cancer that are more likely to develop in someone who has a weakened immune system. These conditions are a sign that HIV has progressed to AIDS.

HIV is spread when blood, semen, or vaginal fluids from an infected person enter another person's body, usually through sexual contact, from sharing needles when injecting drugs, or from mother to baby during birth.

HIV is rarely spread by blood transfusions or organ transplants in the United States because of improved screening procedures.

Symptoms

Untreated HIV infection progresses in stages. These stages are based on your symptoms and the amount of the virus in your blood. Most people go through the following stages after being infected with HIV:

Acute retroviral syndrome

Acute retroviral syndrome is an illness with symptoms like mononucleosis. It often develops within a few days of infection with HIV, but it may occur several weeks after the person is infected. Symptoms may include:

  • Abdominal cramps, nausea, or vomiting.
  • Diarrhea.
  • Enlarged lymph nodes in the neck, armpits, and groin.
  • Fever.
  • Headache.
  • Muscle aches and joint pain.
  • Skin rash.
  • Sore throat.
  • Weight loss.

These first symptoms can range from mild to severe and usually disappear on their own after 2 to 3 weeks. But many people do not have symptoms or they have such mild symptoms that they do not notice at this stage.

Initial stage (stage 1)

The first stage of HIV infection is defined by the CDC as a CD4+ cell count of at least 500 cells per microliter or a percent of CD4+ cells at least 29% of all lymphocytes. People in this stage do not have any symptoms.4

Chronic stage (stage 2)

The second stage of HIV infection is defined by the CDC as a CD4+ cell count of 200 to 499 or a percent of CD4+ cells of 14% to 28%.4 It may take years for HIV symptoms to develop during this stage. But even though no symptoms are present, the virus is multiplying (or making copies of itself) in the body during this time. HIV multiplies so quickly that the immune system cannot destroy the virus. After years of fighting HIV, the immune system starts to weaken.

A doctor may suspect HIV if symptoms persist or if a cause of the symptoms (such as the flu) can't be identified. HIV may also be suspected when several of the following symptoms are present:

  • Diarrhea or other bowel changes
  • Fatigue
  • Fever
  • Loss of appetite or unexplained weight loss
  • Dry cough or shortness of breath
  • Nail changes
  • Night sweats
  • Swollen lymph nodes in the neck, armpits, and groin
  • Pain when swallowing
  • Confusion, trouble concentrating, or personality changes
  • Repeated outbreaks of cold sores or genital herpes sores
  • Tingling, numbness, and weakness in the limbs
  • Mouth sores or a yeast infection of the mouth (thrush)
Symptoms in women and children

Also, HIV may be suspected when a woman has at least one of the following:

Children who have HIV often have different symptoms (for example, delayed growth or an enlarged spleen) than teens or adults.

AIDS (stage 3)

AIDS is the last stage of infection with HIV. AIDS occurs when the CD4+ cell counts drop below 200, the percentage of CD4+ cells is less than 14%, or an AIDS-defining condition is present.5 After your immune system starts to weaken, you are more likely to develop certain infections or illnesses, called opportunistic infections. Examples include some types of pneumonia or cancer that are more common when you have a weakened immune system. If HIV goes untreated, AIDS develops in most people within 10 to 12 years after the initial infection. With treatment for HIV, the progression to AIDS may be delayed or prevented.

A small number of people who are infected with HIV are rapid progressors. They develop AIDS within a few years if they do not receive treatment. It is not known why the infection progresses faster in these people.

What Happens

There are two types of HIV:

  • HIV-1, which causes almost all the cases of AIDS worldwide
  • HIV-2, which causes an AIDS-like illness. HIV-2 infection is uncommon in the United States.

How the disease is spread

HIV is spread when blood, semen, or vaginal fluids from an infected person enter another person's body, usually through:

  • Sexual contact. The virus may enter the body through a tear in the lining of the rectum, vagina, urethra, or mouth. About 87% of all cases of HIV are transmitted by sexual contact.6
  • Infected blood. HIV can be spread when a person:
    • Shares needles, syringes, cookers, cotton, cocaine spoons, or eyedroppers used for injecting drugs or steroids.
    • Is accidentally stuck with a needle or other sharp item that is contaminated with HIV.

It is now extremely rare in the United States for HIV to be transmitted by blood transfusions or organ transplants. Blood and organ donors are screened for risk factors. All donated blood and organs are screened for HIV.

Spread of HIV to babies

A woman who is infected with HIV can spread the virus to her baby during pregnancy, delivery, or breast-feeding.

  • Most children younger than 13 years who have HIV were infected with the virus by their mothers.
  • The risk of a woman spreading HIV to her baby can be greatly reduced if she is on medicine that reduces her viral load (HIV RNA) to undetectable levels during pregnancy, if she continues antiretroviral therapy during pregnancy, and if she does not breast-feed her baby. The baby should also receive treatment after it is born. Treatment of a baby shortly after birth greatly reduces the chance that the baby will die from the HIV infection.7

Ways HIV cannot be spread

HIV does not survive well outside the body. So HIV cannot be spread through casual contact with an infected person, such as by sharing drinking glasses or by casual kissing. HIV is not transmitted through contact with an infected person's saliva, sweat, tears, urine, or feces, or through insect bites.

Contagious and incubation period

The incubation period—the time between when a person is first infected with HIV and when early symptoms develop—may be a few days to several weeks.

It can take as little as 2 weeks or as long as 6 months from the time you become infected with HIV for the antibodies to be detected in your blood. This is commonly called the "window period," or seroconversion period. During the window period, you are contagious and can spread the virus to others. If you think you have been infected with HIV but you test negative for it, you should be tested again. Tests at 6, 12, and 24 weeks can be done to be sure you are not infected.

After you become infected with HIV, your blood, semen, or vaginal fluids should always be considered infectious, even if you receive treatment for the HIV infection.

Stages of HIV

Most people go through the following stages after being infected with HIV if the infection is not treated:

  • Acute retroviral syndrome , which may have symptoms similar to mononucleosis. This often develops within a few days of infection, but may occur several weeks after the person is infected.
  • HIV without symptoms (asymptomatic). It may take years for HIV symptoms to develop. But even though no symptoms are present, the virus is multiplying (or making copies of itself) in the body during this time. HIV multiplies so quickly that the immune system cannot destroy the virus. After years of fighting HIV, the immune system starts to weaken.
  • HIV with symptoms (symptomatic). After your immune system starts to weaken, you are more likely to develop certain infections or illnesses, such as some types of pneumonia or cancer that are more common in people who have a weakened immune system.
  • AIDS, which occurs during the last stage of infection with HIV. If HIV goes untreated, AIDS develops in most people within 10 to 12 years after the initial infection. With treatment for HIV, the progression to AIDS may be delayed or prevented.

A small number of people who are infected with HIV are rapid progressors. They develop AIDS within a few years if they do not receive treatment. It is not known why the infection progresses faster in these people.

Nonprogressors and HIV-resistant

A few people have HIV that does not progress to more severe symptoms or disease. They are referred to as nonprogressors.

A small number of people never become infected with HIV despite years of exposure to the virus. For example, they may have repeated, unprotected sex with an infected person. These people are said to be HIV-resistant.

What Increases Your Risk

Most people get HIV by having unprotected sex with someone who has HIV. Another common way of getting the virus is by sharing needles with someone who is infected with HIV when injecting drugs.

You have an increased risk of becoming infected with HIV through sexual contact if you:

  • Have unprotected sex (do not use condoms).
  • Have multiple sex partners.
  • Are a man who has sex with other men.
  • Have high-risk partner(s) (partner has multiple sex partners, is a man who has sex with other men, or injects drugs).
  • Have or have recently had a sexually transmitted infection, such as syphilis or active herpes.

People who inject drugs or steroids, especially if they share needles, syringes, cookers, or other equipment used to inject drugs, are at risk of being infected with HIV.

Babies who are born to mothers who are infected with HIV are also at risk of infection.

What to think about

HIV may be spread more easily in the early stage of infection, and again later, when symptoms of HIV-related illness develop.

The risk of getting HIV from a blood transfusion or organ transplant is extremely low because all donated blood and organs in the United States are screened for HIV.

When To Call a Doctor

Known HIV infection

If you are infected with HIV or caring for someone who is, call 911 or other emergency services immediately if any of the following conditions develop:

  • Seizures
  • Loss of consciousness
  • New weakness in an arm, a leg, or one side of the body
  • New inability to move a body part (paralysis)
  • New inability to stand or walk

Call your doctor if any of the following conditions develop:

  • Fever higher than 101°F (38.3°C) for 24 hours or a fever higher than 103°F (39.4°C)
  • Shortness of breath
  • Cough that produces mucus or sputum
  • New changes in balance or sensation (numbness, tingling, or pain)
  • Ongoing diarrhea
  • Unusual bleeding, such as from the nose or gums, blood in the urine or stool, or easy bruising
  • Ongoing headache or changes in vision
  • Rapid, unexplained weight loss
  • Night sweats
  • Fatigue
  • Swelling of lymph nodes in the neck, armpits, or groin
  • Unusual sores, rashes, or bumps on the skin or around the genitals, anus, mouth, or increased outbreaks of cold sores
  • Personality changes or decline in mental ability, such as confusion, disorientation, or an inability to do mental tasks that the person has done in the past

Suspected or known exposure to HIV and symptoms are present

Many people have a flu-like illness 3 to 6 weeks after they are first infected with HIV, but symptoms can occur within a few days of infection. Symptoms of acute retroviral syndrome (such as nausea and headache), which are the first signs of HIV infection, are often mistaken for symptoms of another viral infection.

Call your doctor to find out whether HIV testing is needed if you suspect you have been exposed to HIV, particularly if you engage in high-risk behavior and have any of the following symptoms:

  • Abdominal cramps, nausea, or vomiting
  • Diarrhea
  • Enlarged lymph nodes in the neck, armpits, and groin
  • Fever
  • Headache
  • Muscle aches and joint pain
  • Skin rash
  • Sore throat
  • Unexplained weight loss
  • Yeast infection of the mouth (thrush)

Initial symptoms of HIV infection may be mild to severe and usually disappear on their own after 2 to 3 weeks.

Suspected or known exposure to HIV but symptoms are not present

If you have not been tested for HIV, call your doctor if:

  • You suspect that you have been exposed to HIV.
  • You have engaged in high-risk behavior and are concerned that you were exposed to HIV.
  • Your sex partner engages in high-risk behavior.
  • Your sex partner may have been exposed to HIV.
  • Your sex partner has HIV.
  • You develop any of the symptoms listed above.

Getting tested for HIV can be scary, but the condition can be managed with treatment. So it is important to get tested if you think you have been exposed. Early detection and monitoring of HIV will help your doctor find out whether the disease is getting worse and when to start treatment.

Watchful waiting

Watchful waiting is a wait-and-see approach. Until you know the results of your test:

  • Avoid sexual contact with others. If you do have sex, practice safe sex, such as using a condom.
  • Do not share needles, syringes, cookers, cotton, cocaine spoons, or eyedroppers.

If you do not have symptoms of HIV even though you have tested positive for the virus, you and your doctor may simply continue to watch for symptoms to occur. If you do not show any signs of disease and your CD4+ cell count is more than 500 cells per microliter (mcL), you may not need treatment. But during this time you still need regular checkups with a doctor to monitor your viral load and CD4+ cell counts. These tests measure the amount of HIV in your blood and detect how well your immune system is working.

Who to see

Health professionals who can diagnose and may treat HIV include:

HIV can also be diagnosed and treated at an HIV care clinic.

Complications of HIV may require treatment by the following doctors:

If you do not have a doctor

Public health clinics and other organizations may provide free or low-cost, confidential testing and counseling about HIV and high-risk behavior. If you have questions about the testing procedure, ask your doctor to explain the procedure to you.

If you do not have a doctor, contact one of the following for information on HIV testing in your area:

  • Your county or state health department
  • Local AIDS organization
  • Centers for Disease Control and Prevention (CDC) 24-hour information hotline: 1-800-232-INFO (1-800-CDC-4636). Or see the CDC National HIV Testing Resources website at www.hivtest.org.
  • National Association of People with AIDS (NAPWA) hotline: 1-866-846-9366 (toll-free). Or see the NAPWA website at www.napwa.org.
  • U.S. National Institutes of Health (NIH) toll-free HIV hotline: 1-800-HIV-0440 (1-800-448-0440). Or see the NIH AIDS website at www.aidsinfo.nih.gov.

To prepare for your appointment, see the topic Making the Most of Your Appointment.

Exams and Tests

Getting tested for HIV can be scary, but the condition can be managed with treatment. So be sure to get tested if you think you have been exposed. If you test positive, early detection and monitoring of HIV will help your doctor find out whether the disease is getting worse and when to start treatment.

Your doctor may recommend counseling before and after HIV testing, and it is usually available at the hospital or clinic where you will be tested. This will give you an opportunity to:

  • Discuss your fears about being tested.
  • Learn how to reduce your risk of becoming infected if your test is negative.
  • Learn how to keep from spreading HIV to others if your test is positive.
  • Think about personal issues, such as how having HIV will affect you socially, emotionally, professionally, and financially.
  • Learn what you need to do to stay healthy as long as possible.

HIV is diagnosed when antibodies to HIV are detected in the blood. The two primary blood tests used to detect the HIV antibodies are:

  • Enzyme-linked immunosorbent assay (ELISA).
  • Western blot assay, used to confirm the results of a positive ELISA test.

HIV is diagnosed only after two or more positive ELISA tests are confirmed by one positive Western blot assay. These tests usually can be done on the same blood sample.

It can take as little as 2 weeks or as long as 6 months from the time you become infected with HIV for the antibodies to be detected in your blood. This is commonly called the "window period," or seroconversion period. During the window period, you are contagious and can spread the virus to others. If you think you have been exposed to HIV but you test negative for it, you should be tested again. Tests at 6, 12, and 24 weeks can be done to be sure you are not infected.

Testing positive for HIV infection

Testing positive for HIV will probably make you anxious and afraid about your future. The good news is that people being treated for HIV are living longer than ever before with the help of medicines that can often prevent AIDS from developing. Your doctor can help you understand your condition and how best to treat it.

If you test positive for HIV, your doctor will complete a medical history and physical exam. He or she may order several lab tests to evaluate your overall health condition and identify current or previous infections that may become more complicated because of HIV. These tests include:

Some strains of HIV may be resistant to certain medicines. If you tested positive for HIV, your doctor may test you at this stage to see if you have been infected with a drug-resistant strain of HIV. This will help him or her figure out which medicines to use when the infection is treated.

Your doctor will use the results of the physical exam and lab tests at later exams to find out the progression of HIV.

What to think about

The Centers for Disease Control and Prevention (CDC) recommends HIV screening as part of routine blood testing. You and your doctor can decide if testing is right for you.

Most test facilities will have the ELISA test results in 2 to 4 days. Results of the Western blot take longer, 1 to 2 weeks. Rapid antibody tests are available that give results right away. But positive results of the rapid test need to be confirmed by a ELISA or Western blot test.

Call and ask for your HIV test results if you have not been contacted within 1 to 2 weeks of being tested.

Denial, fear, and depression are common reactions to a diagnosis of HIV. Don't be afraid to ask for the emotional support you need. If your family and friends are unable to provide you with support, a professional counselor can help.

Monitoring of established HIV infection

Two tests will be done regularly to monitor how much HIV is in your blood (viral load) and how the virus is affecting your immune system. The results of these tests may help you make decisions about starting highly active antiretroviral therapy (HAART) or switching to new medicines if the ones you are currently taking are not effective.

  • CD4+ cell counts provide information about the health of your immune system.
  • Viral load measures the amount of HIV in your blood.

Testing for drug resistance

HIV often changes or mutates in the body. Sometimes these changes make the virus resistant to a particular medicine or class of medicines. This means the medicine can no longer slow down or prevent the virus from multiplying or protect the immune system.

Two blood tests are available to detect drug resistance in the virus:

  • Genotyping assays, which detect mutations in the viral genes. Test results are generally available in 1 to 2 weeks.
  • Phenotyping assays, which measure the ability of the virus to grow in cells with antiretroviral medicines. Test results are usually available in 2 to 3 weeks.

The U.S. Department of Health and Human Services (DHHS) recommends that HIV genotype testing should be done for everyone when first diagnosed with HIV infection.8 The results can tell if a person is infected with a resistant strain of HIV. This information helps develop a treatment approach to use when treatment is started.

You also may be tested for drug resistance when you are ready to begin treatment, viral load numbers stop declining during treatment, or viral load numbers become detectable after not being detectable while on treatment.

Drug resistance can occur when:

  • There is a change in the way your body absorbs the medicine.
  • There are interactions between two or more medicines you are taking.
  • The virus changes and no longer responds to the medicines you are taking.
  • You have been infected with a drug-resistant strain of the virus.
  • You have not taken your medicines as prescribed by your doctor.

Other medicines are available that may treat some resistant strains of HIV.

How is AIDS diagnosed?

AIDS is the last and most severe stage of HIV infection. It is diagnosed if the results of your test show that you have:

Early detection

The U.S. Centers for Disease Control and Prevention (CDC) recommends that everyone should get tested for HIV as part of their regular medical care. Also, the United States Preventive Services Task Force (USPSTF) recommends screening tests for HIV if:

  • You or your sex partner(s) engage in high-risk behavior, such as having more than one sex partner or injecting drugs.
  • You are pregnant. Early treatment with highly active antiretroviral therapy (HAART) can reduce the risk of passing HIV to your baby.
  • You have been to a sexually transmitted infection (STI) clinic or a tuberculosis (TB) clinic.

Treatment Overview

The most effective treatment for HIV is highly active antiretroviral therapy (HAART)—a combination of several antiretroviral medicines that aims to control the amount of virus in your body. Other steps you can take include keeping your immune system strong, taking medicines as prescribed, and monitoring your CD4+ (white blood cells) counts to check the effect of the virus on your immune system. If HIV is not treated, it eventually progresses to AIDS, the last and most severe stage of HIV infection. People with AIDS are more likely to develop certain illnesses, called opportunistic infections. Examples include Pneumocystis pneumonia and some cancers. These illnesses are common in people who have weakened immune systems.

The U.S. National Institutes of Health (NIH) recommends that people begin treatment for HIV as soon as they know that they are infected.1 Treatment is especially important for pregnant women, people who have other infections (such as tuberculosis or hepatitis), and people who have symptoms of AIDS.

Treatment to prevent infection (postexposure prophylaxis)

Health care workers who are at risk for HIV because of an accidental needlestick or other exposure to body fluids may need medicine to prevent infection.9 Medicine may also prevent HIV infection in a person who has been raped or was accidentally exposed to the body fluids of a person who may have HIV.10 This type of treatment is usually started within 72 hours of the exposure.

Studies have shown that treatment with antiretroviral medicine also can reduce the risk of an uninfected person getting infected through sex.11, 12

Initial treatment

If you are diagnosed with HIV infection during the initial symptoms of early HIV (acute retroviral syndrome), discuss the use of highly active antiretroviral therapy (HAART) with your doctor. Information about treatment of early HIV from clinical trials suggests that treatment of early HIV with antiretroviral medicines has long-term benefits.8 The NIH recommends that people begin treatment for HIV as soon as they know that they are infected.1

HAART medicines that are most often used to treat HIV infection include:

The U.S. National Institutes of Health recommends one of the following drug combinations for people who begin treatment for HIV:8

  • Efavirenz + tenofovir + emtricitabine
  • Ritonavir-boosted atazanavir + tenofovir + emtricitabine
  • Ritonavir-boosted darunavir + tenofovir + emtricitabine
  • Raltegravir + tenofovir + emtricitabine

Other alternative drug combinations are approved and may be used in some situations.

You may decide not to get treated right after you find out that you have HIV. But if you put off treatment, you will still need regular checkups with a doctor to monitor your viral load and CD4+ cell counts. These tests measure the amount of HIV in your blood and detect how well your immune system is working.

Click here to view a Decision Point. HIV: When Should I Start Taking Antiretroviral Medicines for HIV Infection?

You may also want to start HIV treatment if your sex partner does not have HIV. Treatment of your HIV infection can help prevent the spread of HIV to your sex partner.8

Lifestyle choices that can help keep your immune system strong include:

  • Quit smoking. People with HIV are more likely to have a heart attack or get lung cancer.2, 3 Cigarette smoking can increase these risks even more. For more information, see the topic Quitting Smoking.
  • Limit your use of alcohol. Abuse of alcohol increases the rate of HIV progression. For more information, see the topic Alcohol Abuse and Dependence.
  • Eat a healthy, balanced diet. Getting adequate protein and calories may help your immune system fight the HIV infection and improve your overall health. For more information, see the topic Healthy Eating.
  • Exercise regularly to reduce stress and help you feel better. For more information, see the topic Stress Management.
  • Do not use illegal drugs. Using drugs that you inject into a vein increases the risk of HIV progression, though the reasons for this are not clear. The illegal use of injected drugs can make it harder to follow a treatment plan and increases the risk of transmitting HIV to others. Abuse of marijuana, cocaine (crack), and other drugs also can cause HIV to progress more rapidly.

Learning how to live with HIV infection may also keep your immune system strong, while also preventing the spread of HIV to others.

Counseling is another treatment that can improve your quality of life while you are living with HIV. It can help you manage anxiety and depression, which commonly occur with an HIV diagnosis.

For more information, see:

If your partner has HIV:

Treatment if HIV progresses to AIDS

If HIV progresses to a late stage, HAART will be started or continued to keep your immune system as healthy as possible. If you get any diseases that point to AIDS, such as Pneumocystis pneumonia or Kaposi's sarcoma, your doctor will treat them.

Measuring the effectiveness of medicine therapy

Your doctor will measure the effectiveness of your medicine treatment plan by monitoring your CD4+ cell count and viral load.

Treatment failure

If your viral load does not drop as expected, or your CD4+ cell count starts to fall, your doctor will try to find out why the medicines are not working.

There are two main reasons that treatment fails:

  • The HIV has become drug-resistant. The medicines no longer effectively control virus multiplication nor protect the immune system. Tests can help your doctor and you find out whether drug resistance has occurred. You may need a different combination of medicines.
  • You did not take your medicine as prescribed. If you have trouble taking the medicines exactly as prescribed, talk with your doctor.

Even though HIV treatment is now more successful at prolonging life, if HIV progresses to AIDS, certain types of severe infections develop that can lead to death. Left untreated, AIDS is often fatal within 18 to 24 months after it develops. Death may occur sooner in people who rapidly progress through the stages of HIV or in young children.

Many important end-of-life decisions can be made while you are active and able to communicate your wishes. For more information, see the topic Care at the End of Life.

What to think about

Denial, fear, and depression are common reactions to a diagnosis of HIV. Don't be afraid to ask for the emotional support you need. If your family and friends are unable to provide you with support, a professional counselor can help.

Treatment options for HIV are changing often, and experts debate which treatment is best. Talk to your doctor about the treatment that may be best for you.

Alternative and complementary treatments for HIV need to be carefully evaluated. Some people with HIV may use these types of treatment to help with fatigue and weight loss caused by HIV infection and reduce the side effects caused by HAART. Some alternative treatments for HIV or other illnesses (such as St. John's wort) may interfere with your HIV medicines. It is important to discuss alternative treatments with your doctor before trying them.

If you are a caregiver of a person whose HIV has progressed, you can help by providing home care such as giving medicines and learning what to do in case of an emergency. Be sure you also take care of yourself, such as sharing your frustrations with others who share a similar experience.

Prevention

You can keep from getting HIV by avoiding behaviors that might result in contact with infected blood, semen, or vaginal fluids.

  • Practice safe sex to prevent HIV. Always use a condom during sexual activity, unless you are in a relationship with one partner who does not have HIV or other sex partners.
  • If you do have sex with someone who has HIV, it is important to practice safe sex and to be regularly tested for HIV.
  • Reduce your number of sex partners, preferably to one partner.
  • Talk with your sex partner or partners about their sexual history as well as your own sexual history. Find out whether your partner has engaged in high-risk behaviors, such as having more than one sex partner or injecting drugs.
  • Avoid alcohol and drugs, which can impair both your judgment and your immune system. People who know and understand safer sex practices may not practice them when they are under the influence of alcohol or drugs.
  • Do not share intravenous (IV) needles, syringes, cookers, cotton, cocaine spoons, or eyedroppers with others if you use drugs.

You may also be able to take a combination medicine (tenofovir plus emtricitabine) every day to help prevent infection with HIV. This medicine can lower the risk of getting HIV.12, 13, 11 But the medicine is expensive, and you still need to practice safe sex to keep your risk low.

If you are infected with HIV, you can greatly lower the risk of spreading the infection to your sex partner by starting antiretroviral therapy (ART) when your immune system is still healthy. The U.S. National Institutes of Health (NIH) recommends that people begin treatment for HIV as soon as they know that they are infected.1 A large study sponsored by the NIH found that the risk of spreading HIV to an uninfected partner was reduced by 96% when the HIV-positive partner started treatment before his or her CD4 count dropped below 350.14 This study was done mainly with heterosexual couples, so the effectiveness of HIV treatment in preventing the spread of HIV to a same-sex partner may be different.

If you are HIV-positive (infected with HIV) or have engaged in sex or needle-sharing with someone who could be infected with HIV, take precautions to avoid spreading the infection to others.

  • Tell your sex partner or partners about your behavior and whether you are HIV-positive.
  • Follow safe sex practices, such as using condoms.
  • Do not donate blood, plasma, semen, body organs, or body tissues.
  • Do not share personal items, such as toothbrushes, razors, or sex toys, that may be contaminated with blood, semen, or vaginal fluids.

The risk of a woman spreading HIV to her baby can be greatly reduced if she is on medicine that reduces her viral load (HIV RNA) to undetectable levels during pregnancy, if she continues antiretroviral therapy during pregnancy, and if she does not breast-feed her baby. Babies of HIV-positive mothers should also receive treatment after they are born.

If you do not regularly engage in high-risk behaviors for HIV, such as having unprotected sex or injecting drugs, and you think you may have been exposed this way, contact your doctor as soon as possible. He or she may recommend medicine if your exposure was within the past 72 hours.10

Home Treatment

If you are infected with HIV, you can lead an active life for a long time. There are many steps you can take to maintain your health and prevent the spread of HIV.

  • Learn more about HIV to help you actively participate in your health care decisions.
  • Get the immunizations and the medicine treatment you need to prevent certain infections or illnesses, such as some types of pneumonia or cancer that are more likely to develop in people who have a weakened immune system.
  • Join a support group to share your feelings and seek support from others who are in the same situation.
  • Do not smoke. People with HIV are more likely to have a heart attack or get lung cancer.2, 3 Cigarette smoking can raise these risks even more.
  • Do not use illegal drugs, and limit your use of alcohol.
  • Learn how to handle food properly so you do not get a food-borne illness. For more information, see the topic Food Poisoning and Safe Food Handling.
  • Eat a healthy, balanced diet to keep your immune system strong. Learn how to deal with the weight loss that HIV infection can cause. The TLC diet can help prevent some of the problems, such as high cholesterol, that can be caused by treatment for HIV.15
  • Marijuana has been shown to stimulate the appetite and relieve nausea. Talk to your doctor if you're interested in trying it.
  • Exercise regularly to reduce stress and improve the quality of your life. Take steps to help prevent HIV-related fatigue.

A skilled and knowledgeable caregiver can provide the emotional, physical, and medical care that will improve the quality of life for a person who has HIV. If your partner has HIV:

What to think about

Your doctor will consider certain factors such as drug resistance and medicine side effects in determining how best to treat your HIV infection. Treatment for HIV can help you live longer. But in some people, HIV will progress to AIDS, which is fatal. Many important end-of-life decisions can be made while you are active and able to communicate your wishes. For more information, see the topic Care at the End of Life.

Medications

Medicines are the primary treatment for HIV. Your doctor will usually prescribe several medicines—this is sometimes called an anti-HIV "cocktail"—that keeps HIV from multiplying and helps keep the immune system healthy. In the past a person had to take several doses of HIV medicine every day, which was hard for some people. But over the past few years, this routine has become much simpler. People may take their medicine for HIV only once or twice a day.

Medicines used to treat HIV are called antiretrovirals, and several of these are combined for treatment called highly active antiretroviral therapy, or HAART. Using HAART reduces your risk of developing resistance to HIV medicines. The U.S. National Institutes of Health (NIH) recommends that people begin treatment for HIV as soon as they know they are infected.1

When choosing antiretroviral medicines, your doctor will think about certain things, such as:

  • The medicines' effectiveness in reducing viral load.
  • The likelihood that the virus will become resistant to a certain class of medicine. If you have already been treated with a certain antiretroviral medicine, you or your doctor may already know whether you have a resistance to medicines in that class.
  • Medicine side effects and your willingness to tolerate them.
  • The cost of treatment with medicines.

Medicines also are used to prevent other illnesses that can occur with HIV as the result of a weakened immune system. Certain opportunistic infections, such as some types of pneumonia, can develop when HIV attacks and destroys too many CD4+ cells. If too many CD4+ cells are destroyed, the body can no longer fight off infection.

Medication choices

Antiretroviral therapy

Medicines that prevent HIV from multiplying are called antiretrovirals and include:

Click here to view a Decision Point. HIV: When Should I Start Taking Antiretroviral Medicines for HIV Infection?
Click here to view an Actionset. HIV: Taking Antiretroviral Drugs

The U.S. National Institutes of Health recommends one of the following programs for people who begin treatment for HIV:8

  • Efavirenz + tenofovir + emtricitabine
  • Ritonavir-boosted atazanavir + tenofovir + emtricitabine
  • Ritonavir-boosted darunavir + tenofovir + emtricitabine
  • Raltegravir + tenofovir + emtricitabine

Other alternative drug combinations are approved and may be used in some situations.

Treatment failure

If your viral load does not drop as expected, or if your CD4+ cell count starts to fall, your doctor will try to determine why the treatment was not effective.

There are two main reasons that treatment fails:

  • The virus that causes HIV has become resistant. The medicine no longer effectively controls virus multiplication nor protects your immune system. Tests can show whether resistance has occurred. You may need a different combination of medicines.
  • You did not take your medicine as prescribed. If you have difficulty taking the medicines exactly as prescribed, talk with your doctor.

What to think about

You will have frequent blood tests to monitor your CD4+ cell count and viral load while you are taking medicines to treat HIV.

Taking your medicines as prescribed can keep HIV from multiplying and will help prevent other infections. This also can help keep the virus from becoming resistant to the medicines and prevent problems that can limit future treatment options.

Your medicines may have unpleasant side effects, which sometimes make you feel worse than you did before you started taking them. Talk to your doctor about your side effects. He or she may be able to adjust your medicines or prescribe a different one.

You may be able to take several medicines combined into one pill. This reduces the number of pills you have to take each day.

Surgery

There is no surgical treatment for HIV.

What to think about

People with HIV may need surgery for other conditions. You can have surgery if you are HIV-positive. But you may have a harder time healing after surgery if you have a weakened immune system.

Other Treatment

HIV can cause emotional, social, and financial stresses that significantly add to the stress of being ill. Accepting that these stresses are present and getting the education and support you need may help you manage them and improve your quality of life as well as the lives of your caregivers.

Other treatment choices

Counseling may help with the strong emotions associated with an HIV diagnosis and can reduce the anxiety and depression that often occur with HIV.

For more information, see:

Reducing stress can help you better manage the HIV illness. Some methods of stress reduction include:

  • Relaxation, which involves breathing and muscle relaxation exercises.
  • Guided imagery, a series of thoughts and suggestions that help you relax.
  • Biofeedback , which teaches you to relax through learning to control a body function that is not normally under conscious control, such as heart rate or skin temperature.
  • Problem solving , which focuses on any current problems in your life and helps you solve them.
  • Acupuncture, which involves the insertion of very thin needles into the skin to stimulate energy flow throughout the body. It may also help reduce the side effects of HIV medicines.

What to think about

Alternative and complementary treatments for HIV need to be carefully evaluated. Some people with HIV may use these types of treatment to help with fatigue and weight loss caused by HIV infection and reduce the side effects caused by HAART. Some complementary therapies for other problems may actually be harmful. For example, St. John's wort decreases the effectiveness of certain prescription medicines for HIV. It is important to discuss complementary therapies with your doctor before trying them.

Other Places To Get Help

Organizations

AIDS InfoNet
P.O. Box 810
Arroyo Seco, NM 87514
Email: AIDSInfoNet@taosnet.com
Web Address: www.aidsinfonet.org
 

The AIDS InfoNet provides information on HIV/AIDS services and treatments in English, Spanish, and other languages (such as Russian, Bulgarian, and Indonesian) for people living with HIV and their caregivers, especially nurses and other first-line treatment providers. This Web site has fact sheets written in non-technical language on subjects such as general HIV/AIDS information, laboratory tests, medicines for HIV/AIDS treatment, and alternative and complementary therapies.


AIDSinfo
P.O. Box 6303
Rockville, MD  20849-6303
Phone: 1-800-HIV-0440 (1-800-448-0440)

(301) 519-0459
Fax: (301) 519-6616
TDD: 1-888-480-3739
Email: contactus@aidsinfo.nih.gov
Web Address: www.aidsinfo.nih.gov
 

The AIDSinfo hotline and Web site are sponsored by the U.S. Department of Health and Human Services. They provide information on HIV/AIDS treatment, prevention, and research. The hotline provides information in English and in Spanish.


American Social Health Association
P.O. Box 13827
Research Triangle Park, NC  27709
Phone: 1-800-227-8922 (STI Resource Center Hotline)

(919) 361-8400
Fax: (919) 361-8425
Email: info@ashastd.org (general information)
Web Address: www.ashastd.org
 

The mission of the American Social Health Association is to improve the health of individuals, families, and communities, with a focus on preventing sexually transmitted diseases and their harmful consequences.


Centers for Disease Control and Prevention (CDC): National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention
1600 Clifton Road
Atlanta, GA  30333
Phone: 1-800-CDC-INFO (1-800-232-4636)
TDD: 1-888-232-6348
Email: cdcinfo@cdc.gov
Web Address: www.cdc.gov/nchstp
 

The National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention is a branch of the Centers for Disease Control and Prevention (CDC). Its website provides information and updates on sexually transmitted diseases (STDs), human immunodeficiency virus (HIV), and tuberculosis (TB). You can also find fact sheets on these health topics.


National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health
NIAID Office of Communications and Government Relations
6610 Rockledge Drive, MSC 6612
Bethesda, MD  20892-6612
Phone: 1-866-284-4107 toll-free
Phone: (301) 496-5717
Fax: (301) 402-3573
TDD: 1-800-877-8339
Web Address: www.niaid.nih.gov
 

The National Institute of Allergy and Infectious Diseases conducts research and provides consumer information on infectious and immune-system-related diseases.


References

Citations

  1. U.S. Department of Health and Human Services Panel on Antiretroviral Guidelines for Adults and Adolescents (2012). Guidelines for the Use of Antiretroviral Agents in HIV-1-Infected Adults and Adolescents. Available online: http://aidsinfo.nih.gov/contentfiles/lvguidelines/adultandadolescentgl.pdf.
  2. Triant VA, et al. (2007). Increased acute myocardial infarction rates and cardiovascular risk factors among patients with HIV disease. Journal of Clinical Endocrinology and Metabolism. Available online: http://jcem.endojournals.org/cgi/rapidpdf/jc.2006-2190v1 (e-pub ahead of print).
  3. Chaturvedi AK, et al. (2007). Elevated risk of lung cancer among people with AIDS. AIDS, 21(2): 207–213.
  4. Schneider E, et al. (2008). Revised surveillance case definitions for HIV infection among adults, adolescents, and children aged < 18 months and for HIV infection and AIDS among children aged 18 months to < 13 years—United States, 2008. MMWR, 57(RR-10): 1–12. Also available online: http://www.cdc.gov/mmwr/PDF/rr/rr5710.pdf.
  5. U.S. Centers for Disease Control and Prevention (1992). 1993 Revised classification system for HIV infection and expanded surveillance case definition for AIDS among adolescents and adults. MMWR, 41(RR-17): 1–19.
  6. Centers for Disease Control and Prevention (2011). Diagnoses of HIV infection and AIDS in the United States and dependent areas, 2009. HIV Surveillance Report, vol. 21. Available online: http://www.cdc.gov/hiv/surveillance/resources/reports/2009report/index.htm.
  7. Violari A, et al. (2008). Early antiretroviral therapy and mortality among HIV-infected infants. New England Journal of Medicine, 359(21): 2233–2244.
  8. U.S. Department of Health and Human Services Panel on Antiretroviral Guidelines for Adults and Adolescents (2011). Guidelines for the Use of Antiretroviral Agents in HIV-1-Infected Adults and Adolescents. Available online: http://www.aidsinfo.nih.gov/ContentFiles/AdultandAdolescentGL.pdf.
  9. Centers for Disease Control and Prevention (2005). Updated U.S. Public Health Services guidelines for the management of occupational exposures to HIV and recommendations for postexposure prophylaxis. MMWR, 50(RR-09): 1–17. Available online: http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5409a1.htm.
  10. Centers for Disease Control and Prevention (2005). Antiretroviral postexposure prophylaxis after sexual, injection-drug use, or other nonoccupational exposure to HIV in the United States. Recommendations from the U.S. Department of Health and Human Services. Available online: http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5402a1.htm.
  11. Grant RM, et al. (2010). Preexposure chemoprophylaxis for HIV prevention in men who have sex with men. New England Journal of Medicine, 363(27): 2588–2599.
  12. U.S. Centers for Disease Control and Prevention (2011). Interim guidance: Preexposure prophylaxis for the prevention of HIV infection in men who have sex with men. MMWR, 60(03): 65–68. Also available online: http://www.cdc.gov/mmwr/preview/mmwrhtml/mm6003a1.htm.
  13. U.S. Centers for Disease Control and Prevention (2011). CDC trial and another major study find PrEP can reduce risk of HIV infection among heterosexuals. Available online: http://www.cdc.gov/nchhstp/newsroom/PrEPHeterosexuals.html.
  14. Cohen MS, et al. (2011). Prevention of HIV-1 infection with early antiretroviral therapy. New England Journal of Medicine, July 18, epub ahead of print (doi:10.1056/NEJMoa1105243).
  15. Lazzaretti RK, et al. (2012). Dietary intervention prevents dyslipidemia associated with highly active antiretroviral therapy in human immunodeficiency virus type 1-infected individuals: A randomized trial. Journal of the American College of Cardiology, 59(11): 979–988.

Other Works Consulted

  • Aberg JA, et al. (2009). Primary care guidelines for the management of persons infected with HIV: 2009 update by the HIV Medicine Association of the Infectious Diseases Society of America. Clinical Infectious Diseases, 49(5): 651–681.
  • American College of Obstetricians and Gynecologists (2008, reaffirmed 2011). Prenatal and perinatal human immunodeficiency virus testing: Expanded recommendations. ACOG Committee Opinion No. 418. Obstetrics and Gynecology, 112(3): 739–742.
  • Antiretroviral Therapy Cohort Collaboration (2003). Prognostic importance of initial response in HIV-1 infected patients starting potent antiretroviral therapy: Analysis of prospective studies. Lancet, 362(9385): 679–686.
  • Del Rio C, Curran JW (2010). Epidemiology and prevention of acquired immunodeficiency syndrome and human inmmunodeficiency virus infection. In GL Mandell et al., eds., Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases, 7th ed., vol. 1, pp. 1635–1661. Philadelphia: Churchill Livingstone Elsevier.
  • Eron JJ Jr, Hirsch MS (2008). Antiviral therapy of human immunodeficiency virus infection. In KK Holmes et al., eds., Sexually Transmitted Diseases, 4th ed., pp. 1393–1421. New York: McGraw-Hill.
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Credits

By Healthwise Staff
Primary Medical Reviewer E. Gregory Thompson, MD - Internal Medicine
Specialist Medical Reviewer Peter Shalit, MD, PhD - Internal Medicine
Last Revised May 17, 2012

Last Revised: May 17, 2012

Author: Healthwise Staff

Medical Review: E. Gregory Thompson, MD - Internal Medicine & Peter Shalit, MD, PhD - Internal Medicine

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