Condition Overview

What is HIV? What is AIDS?

HIV (human immunodeficiency virus) is a virus that attacks the immune system, the body's natural defence 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 doesn't 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.

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 North America.

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 it 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 breastfeeding.

HIV doesn't survive well outside the body. So it can't be spread by casual contact like 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. After a certain point, symptoms reappear and then remain. These symptoms usually include:

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

How is HIV diagnosed?

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

If you have been exposed to HIV, your immune system will make antibodies to try to destroy the virus. Doctors use tests to find these HIV antibodies or antigens in urine, saliva, or blood.

If a test on urine or saliva shows that you are infected with HIV, you will probably have a blood test to confirm the results.

Most doctors use a blood test to diagnose HIV infection. If the test is positive (meaning that HIV antibodies or antigens are found), a test to detect HIV DNA or RNA will be done to be sure.

HIV antibodies may show up in the blood as early as 2 to 4 weeks after contact but can also take as long as 3 to 6 months to show up in the blood. If you think you have been exposed to HIV but you test negative for it:

• Get tested again. A repeat test can be done after a few weeks to be sure you are not infected.
• Meanwhile, take steps to prevent the spread of the virus, in case you do have it.

You can get HIV testing in most doctors' offices, public health units, hospitals, and HIV care clinics.

How is it treated?

The standard treatment for HIV is a combination of medicines called antiretroviral therapy, or ART. 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.

To monitor the HIV infection and its effect on your immune system, a doctor will regularly 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

After you start treatment, it's 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.

How can you prevent HIV?

HIV is often spread by people who don't know they have it. So it's always important to protect yourself and others by taking these steps:

• Practice safer sex. Use a condom every time you have sex (including oral sex) until you are sure that you and your partner aren't 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. 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 safer sex.
• Don't share personal items, such as toothbrushes or razors.
• Never share needles or syringes with anyone.

If you are at high risk for getting infected with HIV, you can take antiretroviral medicine to help protect yourself from HIV infection. Experts may recommend this for:^{footnote 1, footnote 2}

• People whose sexual practices put them at high risk for HIV infection, such as men who have sex with men and people who have many sex partners.
• People who inject illegal drugs, especially if they share needles.
• Adults who have a sex partner with HIV.

To keep your risk low, you still need to practice safer sex even while you are taking the medicine.

Cause

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

After HIV is in the body, it starts to destroy CD4+ cells, which are white blood cells that help the body fight infection and disease.

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.

Symptoms

HIV may not cause symptoms early on. People who do have symptoms may mistake them for influenza (flu) or mono. Early symptoms of HIV are called acute retroviral syndrome. The symptoms may include:

• Belly 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 don't have symptoms or they have such mild symptoms that they don't notice them at this stage.

After the early symptoms go away, an infected person may not have symptoms again for many years. After a certain point, symptoms reappear and then remain.

Untreated HIV infection progresses in stages. These stages are based on your symptoms and the amount of the virus in your blood.

Later symptoms

Later symptoms may include:

• 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).

What Happens

How HIV 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. Most cases of HIV are spread this way.
• 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.

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

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

How HIV is not spread

The virus doesn't survive well outside the body. So HIV cannot be spread through casual contact with an infected person, such as by sharing drinking glasses, by casual kissing, or by coming into contact with the person's sweat or urine.

It is now extremely rare in Canada or the United States for HIV to be transmitted by blood transfusions or organ transplants.

The window period

After you've been infected, it can take 2 weeks to 3 months for your body to start making HIV antibodies.

This means that during this time you could have a negative HIV test, even though you have been infected and can spread the virus to others.

This is commonly called the "window period," or seroconversion period.

Stages of HIV

If the HIV infection is not treated, people go through the following stages:

Initial stage (stage 1)

The first stage of HIV infection is defined as a CD4+ cell count of at least 500 cells per microlitre or a percentage of CD4+ cells at least 29% of all lymphocytes. People in this stage don't have any symptoms.

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 percentage of CD4+ cells of 14% to 28%. It may take years for HIV symptoms to develop during this stage. But even though no symptoms are present, the virus is making copies of itself (multiplying) in the body during this time.

HIV multiplies so quickly that the immune system can't destroy the virus. After years of fighting HIV, the immune system starts to weaken.

AIDS (stage 3)

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.

If HIV isn't treated, most people get AIDS within 10 to 12 years after the initial infection. With treatment for HIV, the progression to AIDS may be delayed or prevented.

After your immune system starts to weaken, you are more likely to get 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.

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

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.

Non-progressors and people who are HIV-resistant

A few people have HIV that doesn't progress to more severe symptoms or disease. They are referred to as non-progressors.

A small number of people never become infected with HIV despite years of exposure to the virus. These people are said to be HIV-resistant.

What Increases Your Risk

Sexual contact

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.

Drug use

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.

Birth mother infected

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

Most children younger than 13 years who have HIV were infected with the virus by their mothers.

When To Call

Known HIV infection

If you are infected with HIV or caring for someone who is, call 9-1-1 or other emergency services immediately if you or the person you care for has:

• 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 you or the person you care for has:

• A high fever or a fever that lasts for 24 hours.
• Shortness of breath.
• Cough that produces mucus (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, or mouth, or increased outbreaks of cold sores.
• Personality changes or a decline in mental ability, such as confusion, disorientation, or an inability to do mental tasks that were possible in the past.

Suspected or known exposure to HIV but no symptoms

If you have not been tested for HIV, call your doctor right away to see if you should start medicine to prevent HIV if:

• You suspect that you have been exposed to HIV.
• You have engaged in high-risk behaviour and are concerned that you were exposed to HIV.
• Your sex partner engages in high-risk behaviour.
• Your sex partner may have been exposed to HIV.
• Your sex partner has HIV.

Public health units, sexual health clinics, and other organizations may provide free or low-cost confidential testing and counselling about HIV and high-risk behaviour.

Examinations and Tests

Early detection

The Public Health Agency of Canada recommends HIV testing for:^{footnote 7}

• Anyone who is or has been sexually active and has never been tested for HIV.
• Anyone who has had unprotected sex with a partner who is HIV-positive or whose HIV status is unknown.
• Women who are pregnant or planning on becoming pregnant.
• Anyone who has shared needles, syringes, spoons or other drug use equipment with someone who is HIV-positive or whose HIV status is unknown.
• Victims of sexual assault.

HIV testing may also be recommended for:

• People with multiple and/or anonymous sex partners.
• Men who have sex with other men.
• Anyone who has tested positive for another sexually transmitted or blood-borne infection, such as syphilis, gonorrhea, chlamydia, hepatitis B, or hepatitis C.

You and your doctor can decide if testing is right for you.

Fear of being tested

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.

Your doctor may recommend counselling before and after HIV testing. 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.

Testing positive for HIV will probably make you anxious and afraid about your future. Denial, fear, and depression are common reactions.

Don't be afraid to ask for the emotional support you need. If your family and friends aren't able to provide you with support, a professional counsellor can help.

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.

Blood tests for HIV

HIV is diagnosed when HIV antibodies or antigens are found in the blood.

A diagnosis of HIV infection is not made until a positive ELISA test is confirmed by a positive test to detect HIV DNA or RNA, such as a PCR test.

Until you know the results of your test:

• Avoid sexual contact with others. If you do have sex, practice safer sex.
• Do not share needles, syringes, cookers, cotton, cocaine spoons, or eyedroppers.

Testing positive for HIV

If you test positive, your doctor will complete a medical history and physical examination.

He or she may order several lab tests to check your overall health, including:

Other tests may be done to check for current or past infections that may become worse because of HIV. You may be tested for:

Ongoing tests

When you have HIV, two tests are done regularly to see how much of the virus 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 treatment or switching to new medicines if the ones you are taking aren't helping.

Testing for drug resistance

HIV often changes or mutates in the body. Sometimes these changes make the virus resistant to certain medicines. Then the medicine no longer works.

Medical experts recommend testing the blood of everyone diagnosed with HIV to look for this drug resistance.^{footnote 3} This information helps your doctor know what medicines to use.

You also may be tested for drug resistance when:

• You are ready to begin treatment.
• You've been having treatment and your viral load numbers stop going down.
• You've been having treatment and your viral load numbers become detectable after not being detectable.

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 a certain kind of infection called an opportunistic infection that is common in people who have weakened immune systems, such as Kaposi's sarcoma or Pneumocystispneumonia.

Treatment Overview

The most effective treatment for HIV is antiretroviral therapy (ART), a combination of several medicines that aims to control the amount of virus in your body. For more information, see Medications.

Other steps you can take include the following:

• Keep your immune system strong by eating right, quitting smoking, and learning how to avoid infection. For more information, see Home Treatment.
• Monitor your CD4+ (white blood cells) counts to check the effect of the virus on your immune system. For more information, see Examinations and Tests.
• See a counsellor to help you handle the strong emotions and stress that can follow an HIV diagnosis. For more information, see Other Treatment.
• Reduce stress so that you can better manage the HIV illness. For more information, see Other Treatment.

Starting treatment

Medical experts recommend that people begin treatment for HIV as soon as they know that they are infected.^{footnote 3, footnote 4} Treatment is especially important for pregnant women, people who have other infections (such as tuberculosis or hepatitis), and people who have symptoms of AIDS.

Research suggests that treatment of early HIV with antiretroviral medicines has long-term benefits, such as a stronger immune system, delay in onset of AIDS, and longer life expectancy.^{footnote 3, footnote 2}

If you put off treatment, you will still need regular checkups to measure the amount of HIV in your blood and your CD4 cell count to see how well your immune system is working.

You may want to start HIV treatment if your sex partner doesn't have HIV. Treatment of your HIV infection can help prevent the spread of HIV to your sex partner.^{footnote 8}

Living with HIV

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

• Learn more about HIV to actively share in health care decisions.
• Join a support groupto share information and emotions relating to HIV.
• Practice safer sex. Use condoms whenever you have sex.
• Learn how to handle food safely so you don't get a foodborne infection.

If your partner has HIV:

Treatment for AIDS

If HIV progresses to a late stage, treatment 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.

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.

Treatment to prevent HIV infection

Health care workers who are at risk for HIV because of an accidental needle stick or other exposure to body fluids may need medicine to prevent infection.^{footnote 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.^{footnote 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.^{footnote 11, footnote 12}

Prevention

Safer sex

Practice safer sex . This includes using a condom 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 safer sex and to be regularly tested for HIV.

Talk with your sex partner or partners about their sexual history as well as your own sexual history. Find out whether your partner has a history of behaviours that increase his or her risk for HIV.

You may 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.^{footnote 11, footnote 13, footnote 14} But the medicine is expensive, and you still need to practice safer sex to keep your risk low.

Alcohol and drugs

If you use alcohol or drugs, be very careful. Being under the influence can make you careless about practicing safer sex.

And never share intravenous (IV) needles, syringes, cookers, cotton, cocaine spoons, or eyedroppers with others if you use drugs.

If you already have HIV

If you are infected with HIV, you can greatly lower the risk of spreading the infection to your sex partner by starting treatment when your immune system is still healthy.

Experts recommend starting treatment as soon as you know you are infected.^{footnote 3}

Studies have shown that early treatment greatly lowers the risk of spreading HIV to an uninfected partner.^{footnote 15, footnote 16}

Your partner may also be able to take medicine to prevent getting infected.^{footnote 1} This is called pre-exposure prophylaxis (PrEP).

Steps to avoid spreading HIV

If you are infected with HIV, you can greatly lower the risk of spreading the infection to your sex partner by starting treatment when your immune system is still healthy.

• Take antiretroviral medicines. Getting treated for HIV can help prevent the spread of HIV to people who are not infected.
• Tell your sex partner or partners about your behaviour and whether you are HIV-positive.
• Follow safer 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.

If you are pregnant

The risk of a woman spreading HIV to her baby can be greatly reduced if she:

• Is on medicine that reduces the amount of virus in her blood to undetectable levels during pregnancy.
• Continues treatment during pregnancy.
• Does not breastfeed her baby.

The baby should also receive treatment after it is born.

Self-Care

If you are infected with HIV, you can lead an active life for a long time.

Make healthy lifestyle choices

• Eat a healthy, balanced diet to keep your immune system strong. A heart-healthy diet can help prevent some of the problems, such as high cholesterol, that can be caused by treatment for HIV.^{footnote 17}
• Learn how to deal with the weight loss that HIV infection can cause.
• Learn how to handle food properly to avoid getting a foodborne illness. For more information, see the topic Foodborne Illness and Safe Food Handling.
• Exercise regularly to reduce stress and improve the quality of your life. Take steps to help prevent HIV-related fatigue.
• Don't smoke. People with HIV are more likely to have a heart attack or get lung cancer.^{footnote 18, footnote 19} Cigarette smoking can raise these risks even more.
• Don't use illegal drugs. And limit your use of alcohol.

Join a support group

Support groups are often good places to share information, problem-solving tips, and emotions related to HIV infection.

You may be able to find a support group by searching the Internet. Or you can ask your doctor to help you find one.

Prevent other illnesses

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.

Tips for caregivers

A skilled 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:

Medicines

Medicines used to treat HIV are called antiretrovirals. Several of these are combined for treatment called antiretroviral therapy, or ART.

When choosing medicines, your doctor will think about:

• How well the medicines reduce viral load.
• How likely it is that the virus will become resistant to a certain type of medicine.
• Medicine side effects and your willingness to live with them.

Medicines for HIV may have unpleasant side effects. They may 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.

Medication choices

• Nucleoside/nucleotide reverse transcriptase inhibitors, such as abacavir, emtricitabine, and tenofovir.
• Non-nucleoside reverse transcriptase inhibitors (NNRTIs), such as efavirenz, etravirine, and nevirapine.
• Protease inhibitors (PIs), such as atazanavir, darunavir, and ritonavir.
• Entry inhibitors, such as enfuvirtide and maraviroc.
• Integrase inhibitors, such as raltegravir.

Drug resistance

Resistance to HIV medicines 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.

Using antiretroviral therapy (ART) reduces your risk of developing resistance to HIV medicines.

Treatment failure

If your viral load doesn't drop as expected, or if your CD4+ cell count starts to fall, your doctor will try to find out why the treatment didn't work.

There are two main reasons that treatment fails:

• The virus that causes HIV has become resistant. The medicine no longer works to control virus multiplication or protect your immune system. Tests can show if 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.

Other Treatment

Counselling

Counselling may help you to:

• Deal with strong emotions.
• Reduce anxiety and depression.

Reducing stress

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

Medical cannabis (marijuana)

Cannabis has been shown to stimulate the appetite and relieve nausea. Talk to your doctor if you're interested in trying it.

Alternative treatments

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 antiretroviral therapy (ART).

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.

Make sure to discuss complementary therapies with your doctor before trying them.