HIV (human immunodeficiency virus) is a virus that damages the cells in your immune system and weakens your ability to fight everyday infections and disease.
AIDS (acquired immune deficiency syndrome) is the name used to describe a number of potentially life-threatening infections and illnesses that happen when your immune system has been severely damaged by the HIV virus.
While AIDS cannot be transmitted from 1 person to another, the HIV virus can.
There’s currently no cure for HIV, but there are very effective drug treatments that enable most people with the virus to live a long and healthy life.
With an early diagnosis and effective treatments, most people with HIV will not develop any AIDS-related illnesses and will live a near-normal lifespan.
Symptoms of HIV
There are several symptoms of HIV. Not everyone will have the same symptoms. It depends on the person and what stage of the disease they are in.
Below are the three stages of HIV and some of the symptoms people may experience.
Stage 1: Acute HIV Infection
Within 2 to 4 weeks after infection with HIV, about two-thirds of people will have a flu-like illness. This is the body’s natural response to HIV infection.
Flu-like symptoms can include:
- Night sweats
- Muscle aches
- Sore throat
- Swollen lymph nodes
- Mouth ulcers
These symptoms can last anywhere from a few days to several weeks. But some people do not have any symptoms at all during this early stage of HIV.
Don’t assume you have HIV just because you have any of these symptoms—they can be similar to those caused by other illnesses. But if you think you may have been exposed to HIV, get an HIV test.
Here’s what to do:
- Find an HIV testing site near you—You can get an HIV test at your primary care provider’s office, your local health department, a health clinic, or many other places. Use the HIV Services Locator to find an HIV testing site near you.
- Request an HIV test for recent infection—Most HIV tests detect antibodies (proteins your body makes as a reaction to HIV), not HIV itself. But it can take a few weeks after you have HIV for your body to produce these antibodies. There are other types of tests that can detect HIV infection sooner. Tell your doctor or clinic if you think you were recently exposed to HIV and ask if their tests can detect early infection.
- Know your status—After you get tested, be sure to learn your test results. If you’re HIV-positive, see a health care provider as soon as possible so you can start treatment with HIV medicine. And be aware: when you are in the early stage of infection, you are at very high risk of transmitting HIV to others. It is important to take steps to reduce your risk of transmission. If you are HIV-negative, there are prevention tools like pre-exposure prophylaxis (PrEP) that can help you stay negative.
Stage 2: Clinical Latency
In this stage, the virus still multiplies, but at very low levels. People in this stage may not feel sick or have any symptoms. This stage is also called chronic HIV infection.
Without HIV treatment, people can stay in this stage for 10 or 15 years, but some move through this stage faster.
If you take HIV medicine exactly as prescribed and get and keep an undetectable viral load, you can live and long and healthy life and will not transmit HIV to your HIV-negative partners through sex.
But if your viral load is detectable, you can transmit HIV during this stage, even when you have no symptoms. It’s important to see your health care provider regularly to get your viral load checked.
Stage 3: AIDS
If you have HIV and you are not on HIV treatment, eventually the virus will weaken your body’s immune system and you will progress to AIDS (acquired immunodeficiency syndrome).
This is the late stage of HIV infection.
Symptoms of AIDS can include:
- Rapid weight loss
- Recurring fever or profuse night sweats
- Extreme and unexplained tiredness
- Prolonged swelling of the lymph glands in the armpits, groin, or neck
- Diarrhea that lasts for more than a week
- Sores of the mouth, anus, or genitals
- Red, brown, pink, or purplish blotches on or under the skin or inside the mouth, nose, or eyelids
- Memory loss, depression, and other neurologic disorders
Each of these symptoms can also be related to other illnesses. The only way to know for sure if you have HIV is to get tested. If you are HIV-positive, a health care provider will diagnose if your HIV has progressed to stage 3 (AIDS) based on certain medical criteria.
Many of the severe symptoms and illnesses of HIV disease come from the opportunistic infections that occur because your body’s immune system has been damaged. See your health care provider if you are experiencing any of these symptoms.
But be aware: Thanks to effective treatment, most people in the U.S. with HIV do not progress to AIDS. If you have HIV and remain in care, take HIV medicine as prescribed, and get and keep an undetectable viral load, you will stay healthy and will not progress to AIDS.
HIV is caused by a virus. It can spread through sexual contact, illicit injection drug use or sharing needles, contact with infected blood, or from mother to child during pregnancy, childbirth or breastfeeding.
HIV destroys CD4 T cells — white blood cells that play a large role in helping your body fight disease. The fewer CD4 T cells you have, the weaker your immune system becomes.
How does HIV become AIDS?
You can have an HIV infection, with few or no symptoms, for years before it turns into AIDS. AIDS is diagnosed when the CD4 T cell count falls below 200 or you have an AIDS-defining complication, such as a serious infection or cancer.
How HIV spreads
To become infected with HIV, infected blood, semen or vaginal secretions must enter your body. This can happen in several ways:
1. By having sex: You may become infected if you have vaginal, anal or oral sex with an infected partner whose blood, semen or vaginal secretions enter your body. The virus can enter your body through mouth sores or small tears that sometimes develop in the rectum or vagina during sexual activity.
2. By sharing needles: Sharing contaminated injection drug paraphernalia (needles and syringes) puts you at high risk of HIV and other infectious diseases, such as hepatitis.
3. From blood transfusions: In some cases, the virus may be transmitted through blood transfusions. Hospitals and blood banks screen the blood supply for HIV, so this risk is very small in the U.S. and other upper-middle-income countries. The risk may be higher in low-income countries that are not able to screen all donated blood.
4. During pregnancy or delivery or through breastfeeding: Infected mothers can pass the virus on to their babies. Mothers who are HIV-positive and get treatment for the infection during pregnancy can significantly lower the risk to their babies.
How HIV doesn’t spread
You can’t become infected with HIV through ordinary contact. That means you can’t catch HIV or AIDS by hugging, kissing, dancing or shaking hands with someone who has the infection.
HIV isn’t spread through the air, water or insect bites.
Anyone of any age, race, sex or sexual orientation can be infected with HIV/AIDS. However, you’re at greatest risk of HIV/AIDS if you:
- Have unprotected sex. Use a new latex or polyurethane condom every time you have sex. Anal sex is riskier than is vaginal sex. Your risk of HIV increases if you have multiple sexual partners.
- Have an STI. Many STIs produce open sores on your genitals. These sores act as doorways for HIV to enter your body.
- Use illicit injection drugs. People who use illicit injection drugs often share needles and syringes. This exposes them to droplets of other people’s blood.
HIV infection weakens your immune system, making you much more likely to develop many infections and certain types of cancers.
Infections common to HIV/AIDS
- Pneumocystis pneumonia (PCP). This fungal infection can cause severe illness. Although it’s declined significantly with current treatments for HIV/AIDS, in the U.S., PCP is still the most common cause of pneumonia in people infected with HIV.
- Candidiasis (thrush). Candidiasis is a common HIV-related infection. It causes inflammation and a thick, white coating on your mouth, tongue, esophagus or vagina.
- Tuberculosis (TB). TB is a common opportunistic infection associated with HIV. Worldwide, TB is a leading cause of death among people with AIDS. It’s less common in the U.S. thanks to the wide use of HIV medications.
- Cytomegalovirus. This common herpes virus is transmitted in body fluids such as saliva, blood, urine, semen and breast milk. A healthy immune system inactivates the virus, and it remains dormant in your body. If your immune system weakens, the virus resurfaces — causing damage to your eyes, digestive tract, lungs or other organs.
- Cryptococcal meningitis. Meningitis is an inflammation of the membranes and fluid surrounding your brain and spinal cord (meninges). Cryptococcal meningitis is a common central nervous system infection associated with HIV, caused by a fungus found in soil.
- Toxoplasmosis. This potentially deadly infection is caused by Toxoplasma gondii, a parasite spread primarily by cats. Infected cats pass the parasites in their stools, which may then spread to other animals and humans. Toxoplasmosis can cause heart disease, and seizures occur when it spreads to the brain.
Cancers common to HIV/AIDS
- Lymphoma. This cancer starts in the white blood cells. The most common early sign is painless swelling of the lymph nodes in your neck, armpit or groin.
- Kaposi’s sarcoma. A tumor of the blood vessel walls, Kaposi’s sarcoma usually appears as pink, red or purple lesions on the skin and mouth. In people with darker skin, the lesions may look dark brown or black. Kaposi’s sarcoma can also affect the internal organs, including the digestive tract and lungs.
- HPV-related cancers. These are cancers caused by human papillomavirus (HPV) infection. They include anal, oral and cervical cancer.
1. Wasting syndrome. Untreated HIV/AIDS can cause significant weight loss, often accompanied by diarrhea, chronic weakness and fever.
2. Neurological complications. HIV can cause neurological symptoms such as confusion, forgetfulness, depression, anxiety and difficulty walking. HIV-associated neurocognitive disorders (HAND) can range from mild symptoms of behavioral changes and reduced mental functioning to severe dementia causing weakness and inability to function.
3. Kidney disease. HIV-associated nephropathy (HIVAN) is an inflammation of the tiny filters in your kidneys that remove excess fluid and wastes from your blood and pass them to your urine. It most often affects Black or Hispanic people.
4. Liver disease. Liver disease is also a major complication, especially in people who also have hepatitis B or hepatitis C.
There’s no vaccine to prevent HIV infection and no cure for HIV/AIDS. But you can protect yourself and others from infection.
To help prevent the spread of HIV:
1. Consider preexposure prophylaxis (PrEP). The combination oral drugs emtricitabine plus tenofovir disoproxil fumarate (Truvada) and emtricitabine plus tenofovir alafenamide fumarate (Descovy) can reduce the risk of sexually transmitted HIV infection in people at very high risk. PrEP can reduce your risk of getting HIV from sex by about 99% and from injection drug use by at least 74%, according to the Centers for Disease Control and Prevention. Descovy hasn’t been studied in people who have receptive vaginal sex. The FDA recently approved cabotegravir (Apretude), the first injectable PrEP to reduce the risk of sexually transmitted HIV infection in people at very high risk. The injection is given by a health care provider. After the first two monthly injections, cabotegravir is given every two months. The injection is an option in place of a daily PrEP pill. Your health care provider will prescribe these drugs for HIV prevention only if you don’t already have HIV infection. You will need an HIV test before you start taking any PrEP. The test should then be done every three months for pills or before each injection for as long as you’re taking PrEP. Your health care provider will also test your kidney function before prescribing Truvada and continue to test it every 6 to 12 months. Other regular testing may also be needed. You need to take the pill form every day or closely follow the injection schedule for cabotegravir. They don’t prevent other STIs, so you’ll still need to practice safe sex. If you have hepatitis B, you should be evaluated by an infectious disease or liver specialist before beginning therapy.
2. Use treatment as prevention (TasP). If you’re living with HIV, taking HIV medication can keep your partner from becoming infected with the virus. If you make sure your viral load stays undetectable — a blood test doesn’t show any virus — you won’t transmit the virus to anyone else through sex. Using TasP means taking your medication exactly as prescribed and getting regular checkups.
3. Use post-exposure prophylaxis (PEP) if you’ve been exposed to HIV. If you think you’ve been exposed through sex, needles or in the workplace, contact your health care provider or go to the emergency department. Taking PEP as soon as possible within the first 72 hours can greatly reduce your risk of becoming infected with HIV. You will need to take medication for 28 days.
4. Use a new condom every time you have sex. Use a new condom every time you have anal or vaginal sex. Women can use a female condom. If using a lubricant, make sure it’s water-based. Oil-based lubricants can weaken condoms and cause them to break. During oral sex use a nonlubricated, cut-open condom or a dental dam — a piece of medical-grade latex.
5. Tell your sexual partners if you have HIV. It’s important to tell all your current and past sexual partners that you’re HIV-positive. They’ll need to be tested.
6. Use a clean needle. If you use a needle to inject illicit drugs, make sure it’s sterile and don’t share it. Take advantage of needle-exchange programs in your community. Consider seeking help for your drug use.
7. If you’re pregnant, get medical care right away. If you’re HIV-positive, you may pass the infection to your baby. But if you receive treatment during pregnancy, you can significantly cut your baby’s risk.
8. Consider male circumcision. There’s evidence that male circumcision can help reduce the risk of getting HIV infection.
HIV can be diagnosed through blood or saliva testing. Available tests include:
Antigen/antibody tests. These tests usually involve drawing blood from a vein. Antigens are substances on the HIV virus itself and are usually detectable — a positive test — in the blood within a few weeks after exposure to HIV.
Antibodies are produced by your immune system when it’s exposed to HIV. It can take weeks to months for antibodies to become detectable. The combination antigen/antibody tests can take 2 to 6 weeks after exposure to become positive.
Antibody tests. These tests look for antibodies to HIV in blood or saliva. Most rapid HIV tests, including self-tests done at home, are antibody tests. Antibody tests can take 3 to 12 weeks after you’re exposed to become positive.
Nucleic acid tests (NATs). These tests look for the actual virus in your blood (viral load). They also involve blood drawn from a vein. If you might have been exposed to HIV within the past few weeks, your health care provider may recommend NAT. NAT will be the first test to become positive after exposure to HIV.
Talk to your health care provider about which HIV test is right for you. If any of these tests are negative, you may still need a follow-up test weeks to months later to confirm the results.
Tests to stage disease and treatment
If you’ve been diagnosed with HIV, it’s important to find a specialist trained in diagnosing and treating HIV to help you:
- Determine whether you need additional testing
- Determine which HIV antiretroviral therapy (ART) will be best for you
- Monitor your progress and work with you to manage your health
If you receive a diagnosis of HIV/AIDS, several tests can help your health care provider determine the stage of your disease and the best treatment, including:
- CD4 T cell count. CD4 T cells are white blood cells that are specifically targeted and destroyed by HIV. Even if you have no symptoms, HIV infection progresses to AIDS when your CD4 T cell count dips below 200.
- Viral load (HIV RNA). This test measures the amount of virus in your blood. After starting HIV treatment, the goal is to have an undetectable viral load. This significantly reduces your chances of opportunistic infection and other HIV-related complications.
- Drug resistance. Some strains of HIV are resistant to medications. This test helps your health care provider determine if your specific form of the virus has resistance and guides treatment decisions.
Tests for complications
Your health care provider might also order lab tests to check for other infections or complications, including:
- Hepatitis B or hepatitis C virus infection
- Liver or kidney damage
- Urinary tract infection
- Cervical and anal cancer
Currently, there’s no cure for HIV/AIDS. Once you have the infection, your body can’t get rid of it. However, there are many medications that can control HIV and prevent complications. These medications are called antiretroviral therapy (ART). Everyone diagnosed with HIV should be started on ART, regardless of their stage of infection or complications.
ART is usually a combination of two or more medications from several different drug classes. This approach has the best chance of lowering the amount of HIV in the blood. There are many ART options that combine multiple HIV medications into one pill, taken once daily.
Each class of drugs blocks the virus in different ways. Treatment involves combinations of drugs from different classes to:
- Account for individual drug resistance (viral genotype)
- Avoid creating new drug-resistant strains of HIV
- Maximize suppression of virus in the blood
Two drugs from one class, plus a third drug from a second class, are typically used.
The classes of anti-HIV drugs include:
- Non-nucleoside reverse transcriptase inhibitors (NNRTIs) turn off a protein needed by HIV to make copies of itself.Examples include efavirenz (Sustiva), rilpivirine (Edurant) and doravirine (Pifeltro).
- Nucleoside or nucleotide reverse transcriptase inhibitors (NRTIs) are faulty versions of the building blocks that HIV needs to make copies of itself.Examples include abacavir (Ziagen), tenofovir disoproxil fumarate (Viread), emtricitabine (Emtriva), lamivudine (Epivir) and zidovudine (Retrovir).Combination drugs also are available, such as emtricitabine/tenofovir disoproxil fumarate (Truvada) and emtricitabine/tenofovir alafenamide fumarate (Descovy).
- Protease inhibitors (PIs) inactivate HIV protease, another protein that HIV needs to make copies of itself.Examples include atazanavir (Reyataz), darunavir (Prezista) and lopinavir/ritonavir (Kaletra).
- Integrase inhibitors work by disabling a protein called integrase, which HIV uses to insert its genetic material into CD4 T cells.Examples include bictegravir sodium/emtricitabine/tenofovir alafenamide fumarate (Biktarvy), raltegravir (Isentress), dolutegravir (Tivicay) and cabotegravir (Vocabria).
- Entry or fusion inhibitors block HIV’s entry into CD4 T cells.Examples include enfuvirtide (Fuzeon) and maraviroc (Selzentry).
Starting and maintaining treatment
Everyone with HIV infection, regardless of the CD4 T cell count or symptoms, should be offered antiviral medication.
Remaining on effective ART with an undetectable HIV viral load in the blood is the best way for you to stay healthy.
For ART to be effective, it’s important that you take the medications as prescribed, without missing or skipping any doses. Staying on ART with an undetectable viral load helps:
- Keep your immune system strong
- Reduce your chances of getting an infection
- Reduce your chances of developing treatment-resistant HIV
- Reduce your chances of transmitting HIV to other people
Staying on HIV therapy can be challenging. It’s important to talk to your health care provider about possible side effects, difficulty taking medications, and any mental health or substance use issues that may make it difficult for you to maintain ART.
Having regular follow-up appointments with your health care provider to monitor your health and response to treatment is also important. Let your provider know right away if you’re having problems with HIV therapy so that you can work together to find ways to address those challenges.
Treatment side effects
Treatment side effects can include:
- Nausea, vomiting or diarrhea
- Heart disease
- Kidney and liver damage
- Weakened bones or bone loss
- Abnormal cholesterol levels
- Higher blood sugar
- Cognitive and emotional problems, as well as sleep problems
Treatment for age-related diseases
Some health issues that are a natural part of aging may be more difficult to manage if you have HIV. Some medications that are common for age-related heart, bone or metabolic conditions, for example, may not interact well with anti-HIV medications. It’s important to talk to your health care provider about your other health conditions and the medications you’re taking.
If you are started on medications by another health care provider, it’s important to let the provider know about your HIV therapy. This will allow the provider to make sure there are no interactions between the medications.
Your health care provider will monitor your viral load and CD4 T cell counts to determine your response to HIV treatment. These will be initially checked at 4 to 6 weeks, and then every 3 to 6 months.
Treatment should lower your viral load so that it’s undetectable in the blood. That doesn’t mean your HIV is gone. Even if it can’t be found in the blood, HIV is still present in other places in your body, such as in lymph nodes and internal organs.