HIV and AIDS: A Complete Guide

Human immunodeficiency virus (HIV) is a virus that causes disease by damaging the immune system. When the damage is severe and the body's immune defenses are compromised, a person is said to have acquired immunodeficiency syndrome (AIDS).

HIV therapy protects the immune system by controlling the virus and preventing disease progression.

This article takes a comprehensive look at HIV/AIDS, including the symptoms, causes, stages of infection, and modes of transmission. It also explains how HIV is diagnosed, treated, and prevented, and what to expect if you test positive for HIV.

Child's hands holding an HIV awareness ribbon

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What Is HIV?

HIV stands for the human immunodeficiency virus. The virus targets and attacks a type of white blood cell called a CD4 T-cell lymphocyte. These are the "helper" cells that help coordinate the immune response by stimulating other immune cells to fight infection.

When HIV infects a CD4 T-cell, it inserts its genetic material into the cell and "hijacks" its genetic machinery, turning into an HIV-producing factory. After numerous copies of the virus have been made, the infected cell dies.

As more and more CD4 T-cells are killed off, the immune system loses its ability to defend itself against infections it could otherwise fight. These are called opportunistic infections (OIs).

What Is AIDS?

AIDS stands for acquired immunodeficiency syndrome. It is the most advanced stage of HIV infection when the immune system has been compromised, leaving the body vulnerable to a wide range of potentially life-threatening opportunistic infections.

The status of a person's immune function is measured by a CD4 count. The CD4 count literally counts the number of CD4 T-cells in a sample of blood. The normal CD4 count range is 500 to 1,500 cells per cubic millimeters (cells/mm3) of blood.

You are said to have AIDS when one of two things occurs:

  • Your CD4 count is below 200. This is the point where you are said to be immunocompromised whether you have an OI or not. At this stage, your risk of a severe OI is increased.
  • You have any one of over two dozen different AIDS-defining conditions irrespective of your CD4 count. These are diseases that rarely occur outside of people who are severely immunocompromised.

If left untreated, HIV can progress to AIDS in about eight to 10 years. Some people progress far more quickly.


HIV is a virus that can lead to AIDS if left untreated. AIDS is the most advanced stage of HIV infection where the body's immune defenses have been compromised.

HIV Symptoms

HIV progresses in stages as CD4 T-cells are progressively destroyed. While the progression can vary from one person to the next, there are certain symptoms that are more likely to occur during three phases, broadly referred to as:

  • Acute infection
  • Chronic HIV infection (includes asymptomatic and symptomatic stages)
  • AIDS

Early Symptoms of HIV

Acute HIV infection is the period immediately following exposure to the virus in which the immune system mounts an aggressive defense to control the virus. During this phase, anywhere from 50% to 90% of people will experience flu-like symptoms referred to as acute retroviral syndrome (ARS).

Symptoms of ARS tend to develop with two to four weeks of exposure and may include:

Acute symptoms tend to clear within 14 days but may last for several months in some people. Other people may have no symptoms at all.

Chronic HIV Infection Symptoms

Even after the acute infection has been controlled, the virus does not disappear. Instead, it goes into a period of chronic HIV infection (also called clinical latency) in which the virus persists at lower levels in the bloodstream and continues to "silently" kill CD4 T-cells.

At the same time, the virus will imbed itself in tissues throughout the body called latent reservoirs. These reservoirs effectively hide HIV from detection by the immune system.

Clinical latency is a relatively long period in which there may be few, in any, notable signs or symptoms. If symptoms do occur, they tend to be non-specific and easily mistaken for other illnesses.

Some of the more common OIs experienced during chronic HIV infection include:

Is Rash a Symptom of HIV?

Rashes are a common part of HIV infection. In some cases, the rash may be related to an OI or caused by a hypersensitive reaction to HIV medications.

A rash may also be a sign of acute HIV infection. Research suggests that around 50% of people who seek a diagnosis for acute HIV symptoms will have a rash, sometimes referred to as an "HIV rash."

An HIV rash is described as being maculopapular. This means that there will be flat, reddened patches of skin covered with small bumps.

An HIV rash most often affects the upper body, including the face and chest, but may also develop on the arms, legs, hands, and feet. The rash can be itchy and even painful. In most cases, the rash will clear within a week or two.

HIV Symptoms in Men

The symptoms of HIV are generally the same for all sexes. With that said, males may experience certain symptoms differently or exclusively.

These include sexually transmitted infections (STIs) that commonly occur alongside HIV. In males, symptoms of an STI coinfection may include genital or anal sores, pain with urination, pain with ejaculation, or testicle swelling.

During clinical latency, males with HIV may experience an outbreak of painful ulcers on the penis or anus due to genital herpes. Erectile dysfunction is also common, occurring at a rate three times greater than males without HIV. Gynecomastia (abnormal breast enlargement) can also occur at CD4 counts below 100.

Cancer is also a concern among males living with HIV. Research shows that males with HIV have roughly an eight-fold greater risk of penile cancer and 144-fold greater risk of anal cancer than males without HIV.

HIV Symptoms in Women

STI coinfection in females with HIV can cause pain with urination, vaginal discharge, vaginal itchiness, a fishy vaginal odor, pain with sex, bleeding between menstrual periods, and vaginal sores.

During clinical latency, females with HIV are at higher risk of recurrent yeast infections, abnormal periods, premature menopause, chronic pelvic pain, and infertility compared to females without HIV.

Painful vaginal ulcers may also occur due to an outbreak of genital herpes. Women with HIV are also at a four-fold greater risk of osteoporosis than women in the general population.

During advanced-stage infection, females with HIV are at a six-fold greater risk of invasive cervical cancer at CD4 counts under 200 than those whose CD4 counts are over 500.


The symptoms of HIV vary by the stage of infection, with some people experiencing few if any symptoms until the disease is advanced. Symptoms of HIV can also vary by sex, including changes in sexual function and an increased risk of diseases affecting the sexual organs.

AIDS Symptoms

The symptoms of AIDS can vary by the type of opportunistic infection a person gets. During advanced-stage infection, AIDS-defining illnesses can affect practically every organ system of the body, including the blood, brain, digestive tract, eyes, lungs, skin, mouth, and genitals.

Examples include:

 Organ  AIDS-Defining Condition  Symptoms
Blood Non-Hodgkin lymphoma (NHL) Recurrent fever, persistent fatigue, swollen lymph nodes, chest pain, trouble breathing, weight loss
Brain HIV-related encephalopathy, cryptococcosis, progressive multifocal leukoencephalopathy (PML), toxoplasmosis Mental deterioration, speech disturbances, memory problems, loss of coordination, vision loss, dementia. seizures, paralysis, coma
Digestive tract Cytomegalovirus (CMV). cryptosporidiosis, Mycobacterium avium complex (MAC) Chronic diarrhea, stomach cramps, nausea, vomiting, fatigue, loss of appetite, vomiting, weight loss
 Eyes Cytomegalovirus (CMV) Blurry vision and, in severe cases, blindness
 Lungs Coccidioidomycosis, histoplasmosis, Pneumocystis pneumonia, tuberculosis Recurrent fever, difficulty breathing, weight loss, night sweats, fatigue
 Skin Kaposi sarcoma (KS) Purplish, brown, or red spots on the skin that can eventually internalize


The symptoms of AIDS vary by the opportunistic infection and the organ affected. AIDS-defining illnesses can affect practically every organ system of the body.

Facts About HIV Transmission

HIV can be passed through bodily fluids such as semen, blood, vaginal fluids, anal fluids, and breast milk. With that said, some modes of transmission are more effective than others.

Ways That HIV Is Transmitted

Some of the ways that HIV can be effectively transmitted (passed) from one person to the next include:

There is little to no risk of transmitting HIV through oral sex as enzymes in the saliva appear to be effective in neutralizing the virus. Similarly, the risk of transmission from blood transfusions is low due to the routine screening of the blood supply in the United States.

Tattooing, body piercing, and dental procedures are theoretical sources of HIV infection.

Ways That HIV Cannot Be Transmitted

According to the Centers for Disease Control and Prevention (CDC), HIV cannot be transmitted in the following ways:

  • Closed mouth kissing
  • Touching (including hugging and shaking hands)
  • Sharing utensils or dishes
  • Sharing toilet seats
  • Through mosquitos, ticks, or other insects
  • Through contact with saliva, sweat, or tears
  • Through the air


HIV is commonly transmitted through anal sex, vaginal sex, and shared needles. It can also be passed from mother to child during pregnancy or breastfeeding. Healthcare workers are at risk of infection from needlestick injuries and other occupational injuries.

Origin of HIV

HIV is a type of virus that is believed to have made the jump from animals to humans. There are two types of HIV that not only have different genetic origins but different rates of infectivity (the ability to be transmitted) and virulence (the ability to cause disease):

  • HIV-1: This is the main type of HIV that is thought to have originated in chimpanzees and gorillas of West Africa. HIV-1 accounts for around 95% of all infections worldwide. It is also more virulent and associated with faster disease progression than HIV-2.
  • HIV-2: Genetic research suggests that HIV-2 originated in the sooty mangabey monkey. Because it is far more difficult to transmit, HIV-2 is mainly confined to West Africa. Although it is less virulent than HIV-1, some HIV medications do not work as well against this type of HIV.


HIV-1 is thought to have made the leap from chimpanzees and gorillas to humans, while HIV-2 is believed to have originated in the sooty mangabey monkey. HIV-1 is seen worldwide and accounts for the vast majority of infections, while HIV-2 is mainly confined to West Africa.

Diagnosing HIV

HIV is diagnosed with blood, oral fluid, or urine tests. These include point-of-care (POC) tests that are performed in a medical office and in-home tests that can be purchased online or at drugstores.

In addition to traditional lab-based tests, there are rapid tests (both POC and in-home versions) that can deliver results in as few as 20 minutes.

The tests deliver either a positive result (meaning that you have HIV) or a negative result (meaning that you don't have HIV).

When confirmed with a second approved testing method, HIV tests are extremely accurate with a low rate of false positives (a positive result when you don't have HIV) and false negatives (a negative result when you do have HIV).

Antibody Tests

Antibody-based HIV tests detect proteins, called antibodies, that are produced by the immune system in response to HIV. HIV antibodies can be found in blood, oral fluid, and urine.

There are several HIV antibody tests approved in the United States:

  • Standard point-of-care test: Require a blood draw from a vein, the sample of which sent to a lab for testing
  • Rapid point-of-care tests: A test performed on oral fluid
  • OraQuick In-Home Test: A home version of the rapid point-of-care oral test
  • Home Access HIV-1 Test System: A home test that requires the user to user to prick their finger and send a blood drop to a licensed lab

A positive result needs to be confirmed with a second test, most commonly a blood test known as the Western blot.

Combination Antibody/Antigen Tests

Combination antibody/antigen tests are the common method of HIV testing in the United States. The test not only detects HIV antibodies in the blood but also proteins on the surface of the virus itself called antigens.

Combination antibody/antigen tests allow for the accurate detection of HIV in a shorter period of time after infection than an antibody test alone.

Combination antibody/antigen tests are commonly performed as a point-of-care test using blood from a vein. There is also a POC version that requires a finger prick.

Nucleic Acid Test (NAT)

A nucleic acid test (NAT) is not used for general screening purposes. Unlike the other tests, it looks for the actual virus in a sample of blood based on its genetic material. The NAT can not only tell if you have HIV but also how many viruses there are in the blood sample.

While a NAT can detect HIV sooner than the other types of tests, it is very expensive and is mainly used if there has been a recent high-risk exposure or there are early signs of HIV.

The NAT can also be used if initial HIV test results are indeterminate (neither positive nor negative). It is used to screen donated blood or test newborns suspected of having HIV.

What Is the Window for HIV?

The HIV window period is the time between exposure to HIV and when it becomes detectable in blood or saliva tests. An HIV test may show a negative result during the window period even if you have HIV. You can still pass the virus to others during this period even though a test didn't detect the virus.

The HIV window period differs by the testing method used:

  • Nucleic acid test (NAT): 10 to 33 days after exposure
  • Antigen/antibody test (blood draw): 18 to 45 days after exposure
  • Antigen/antibody test (finger prick): 18 to 90 days after exposure
  • Antibody test: 23 to 90 days after exposure

If you think you may have been exposed to HIV but tested negative, it could be because you tested too early. In such cases, you may be advised to return in several weeks or months to get retested.


HIV can be diagnosed with antibody tests, antibody/antigen tests, and nucleic acid (NAT) tests. Antibody tests can be performed on blood or oral fluid, while NAT and antibody/antigen tests require a sample of blood. There are also rapid antibody tests that can detect HIV in a little as 20 minutes.

Treatment Options

HIV is treated with antiretroviral drugs. This is a group of drugs that are used in combination to control the virus and slow disease progression.

Antiretrovirals work by blocking a stage in the virus' life cycle. Without the means to make complete the life cycle, the virus cannot make copies of itself. The viral population can be reduced to undetectable levels (as measured by the viral load), and the immune system will have the chance to recover (as measured by the CD4 count).

The ultimate goal of antiretroviral therapy is to achieve and sustain an undetectable viral load. Doing so increases life expectancy and reduces the risk of serious HIV-associated and non-HIV-associated illnesses (like cancers) by 72%.

Antiretrovirals do not "cure" HIV. They simply suppress the virus if used as directed. If you stop treatment, the viral population will rebound and relaunch its assault on CD4 cells. At the same time, it can allow drug-resistant mutations to develop in the virus, making your drugs less effective and increasing the risk of treatment failure.


HIV is treated with antiretroviral drugs that prevent the virus from making copies of itself. When used as directed, antiretrovirals can reduce HIV to undetectable levels where it can do the body little harm.

HIV Medications

There are currently six classes of antiretroviral drugs used in combination HIV therapy. Most are delivered in oral form (tablets or liquids), while others are delivered by injection.

Treatment Regimens

The classes of HIV drugs are named after the stage in the life cycle they inhibit (block):

  • Attachment/entry inhibitors: Used to prevent HIV from attaching to and entering a cell
  • Nucleoside reverse transcriptase inhibitors: Used to prevent the virus' genetic material from "hijacking" a cell's genetic coding
  • Non-nucleoside reverse transcriptase inhibitors: Also used to prevent the "hijacking" of a cell's genetic coding, albeit in a different way
  • Integrase inhibitors: Used to prevent the insertion of the viral code into a cell's nucleus
  • Protease inhibitors: Used to prevent the "chopping up" of proteins that serve as the building blocks for new viruses
  • Pharmacokinetic enhancers: Used to "boost" the concentration of certain HIV drugs in the bloodstream so that they work longer

As of 2022, the Food and Drug Administration (FDA) has approved more than two dozen different individual antiretroviral agents. Many of these are used to make fixed-dose combination (FDC) drugs containing two or more antiretrovirals. Some FDC drugs can treat HIV with a single pill taken once daily.

Traditionally, HIV therapy consisted of two or more antiretrovirals taken in one or more doses every day. In 2021, the FDA approved the first extended-relief treatment called Cabenuva which is just as effective in suppressing HIV with only two injections once monthly.

Side Effects

As with all drugs, antiretroviral can cause side effects. Some may occur when treatment is first started, while others develop over time as drug toxicities develop.

Most short-term side effects are relatively mild and tend to clear within several days or weeks. These include:

  • Headache
  • Stomach upset
  • Dizziness
  • Insomnia
  • Vivid dreams
  • Nausea or vomiting
  • Rash

Delayed or longer-term side effects are often more severe. Many of these are due to drug toxicities that tend to affect people with certain pre-existing conditions (such as kidney or liver diseases). Others are due to hypersensitivity reactions in which the immune system suddenly overreacts to a drug.

Some of the possible long-term side effects of HIV therapy include, by complication type:

  • Acute kidney failure: Decreased urine output, fatigue, shortness of breath, nausea, weakness, and irregular heartbeat
  • Drug hypersensitivity: Severe rash or hives, blistering or peeling skin, muscle or joint pain, and rigors (severe shivering with high fever)
  • Lactic acidosis: Weakness, stomach pain, nausea, vomiting, diarrhea, loss of appetite, and rapid, shallow breathing
  • Lipodystrophy: Thinning of the legs and buttocks and/or the enlargement of the breasts, abdomen, or upper back ("buffalo hump")
  • Liver toxicity: Fatigue, stomach pain, nausea, vomiting, and jaundice (yellowing of the skin and eyes)
  • Peripheral neuropathy: Pins-and needles sensations, tingling, numbness, weakness, increased pain sensitivity, poor balance, and slow reflexes


Antiretroviral drugs are expensive. Some studies estimate that the lifetime cost of treatment (including medications, routine blood tests, and doctor's visits) is well in excess of $400,000. Even with copayment and coinsurance, the costs can be prohibitive.

According to a 2020 study published in JAMA Internal Medicine, the average wholesale cost of a recommended first-line therapy in the United States ranged from roughly $37,000 per year to just over $50,000 per year.

Fortunately, there are ways to reduce the cost of antiretroviral therapy even if you don't have insurance. Eligibility for most is based on your family's annual income.

Options include:


There are more than two dozen individual antiretroviral drugs and more than 20 fixed-dosed combination drugs used to treat HIV. Although the cost of treatment is expensive, there are governmental, private, and manufacturer assistance programs that can help cover some or all of the cost.

HIV Prevention

HIV prevention has changed dramatically since time when "ABC" (abstinence, be faithful, condomize) was the catchphrase among many public health officials. Today, there are medical interventions that have proven equally effective in reducing the risk of getting or passing the virus.

Practice Safer Sex

Condoms still remain the frontline defense against HIV. When used correctly and consistently, condoms can reduce the risk of HIV transmission among high-risk men who have sex with men (MSM) by 91%, according to a 2018 study in the journal AIDS.

Equally important is a reduction in your number of sex partners. Studies have consistently shown that people with multiple sexual partners are more likely to be HIV-positive and/or have an STI co-infection than those with only one sex partner.

Avoid Sharing Needles

Sharing needles increases the risk of HIV by allowing for the direct transmission of HIV-infected blood from one person to the next. Also, many illicit drugs can reduce inhibitions, impair judgment, or cause hypersexual behaviors that lead to condomless sex, increasing the risk whether needles are shared or not.

Today, 43 states offer clean needle exchange programs that allow you to access sterile needles and syringes, no questions asked. (Alabama, Delaware, Kansas, Mississippi, Nebraska, South Dakota, and Wyoming currently don't.)

If you are unable to access a clean needle exchange program, you can reduce the risk of transmission by cleaning used needles and syringes with bleach and water immediately after use and just before using them again.

PrEP, PEP, and TasP

HIV pre-exposure prophylaxis (PrEP) is a preventive strategy used in someone who doesn't have HIV. It involves a daily dose of the antiretroviral drug Truvada (emtricitabine/tenofovir DF) or Descovy (emtricitabine/tenofovir), which can reduce the risk of getting HIV by as much as 99%. While effective in preventing HIV, PrEP does not reduce the risk of other STIs.

HIV post-exposure prophylaxis (PEP) is used to avert infection in someone who is accidentally exposed to HIV. It involves a 28-day course of three antiretrovirals drugs which must be started no later than 72 hours from the time of exposure (and ideally sooner).

Treatment as prevention (TasP) is a preventive strategy in which an undetectable viral load in someone with HIV dramatically reduces their risk of infecting others. Studies have shown that a sustained undetectable viral load can cut the odds of infecting a sexual partner to literally zero—a strategy referred to as "U=U" ("Undetectable Equals Untransmissible").


The risk of HIV can be reduced by using condoms, reducing your number of sex partners, and avoiding shared needles. Medication-based strategies include PrEP to avoid getting HIV, TasP to avoid passing HIV, and PEP to avert an infection if accidentally exposed to HIV.

Living With HIV

HIV is a far different disease than it was 20 years ago, with people enjoying long, healthy lives when diagnosed and treated early. Even so, it doesn't minimize the challenges that people with HIV still face when coming to terms with their diagnosis.

Coping Strategies

Living with HIV can be stressful, not only due to concerns about treatment and the cost of care but also due to emotional issues like HIV stigma, the fear of disclosure, and the impact of HIV on relationships, dating, and family planning.

Education is your first step to coping with HIV. By better understanding what HIV is, how your drugs work, and how infection is avoided, you will not only feel less stress but be able to educate others around you, including family and friends.

Among some of the other key coping strategies:

  • Build a support network. This includes your medical team, loved ones you trust, and HIV support groups (both online and in-person).
  • See your healthcare provider as scheduled. People who are consistently linked to care are far more likely to be—and remain—undetectable than those who aren't. This alone reduces stress and anxiety.
  • Live a healthy lifestyle. People with HIV are at greater risk of heart disease, diabetes, and other chronic illnesses. To live well, make positive life choices like quitting cigarettes, exercising regularly, maintaining a healthy weight, and eating a healthy diet.
  • Manage stress. Rather than turning to alcohol, cigarettes, or medications to deal with stress, practice mind-body therapies like meditation, yoga, tai chi, guided imagery, progressive muscle relaxation (PMR), or biofeedback.
  • Seek professional help. If you are unable to cope, do not hesitate to ask for a referral to a therapist or psychiatrist who can offer one-on-one or group counseling.

HIV Life Expectancy

Today, a 20-year-old newly diagnosed with HIV can expect to live a near-normal life expectancy—roughly into their early 70s—if diagnosed and treated early. That's an enormous change from 1996 when the average life expectancy was a mere 10 years.

Even so, there are many things that take back those gains and dramatically reduce the lifespan of someone with HIV. These includes:

  • Delaying treatment: Starting treatment when the CD4 count is below 200 reduces life expectancy by eight years.
  • Injecting drug use: Injecting drugs is also seen to reduce life expectancy in people with HIV by eight years.
  • Smoking: Cigarettes double the risk of early death in people with HIV and reduce life expectancy by around 12 years.

HIV Statistics

HIV does not affect all communities equally. This is especially true of men who have sex with men (MSM) who accounted for 69% of all new infections (despite making up only 2% of the general population).

People of color are also disproportionately affected. This is driven in large part by high rates of poverty, structural racism, and unequal access to health care in Black and Latinx communities. According to the CDC, no less than 76% of people living with HIV In the United States have an annual household income of less than $20,000.

These disparities are reflected in the number of new HIV infections in 2020, by race or ethnicity:

  • Black: 42%
  • Latinx: 29%
  • White: 25%
  • Others: 5%

When risk factors intersect, the likelihood of infection increases. There is arguably no better example of this than Black MSM in the United States. Faced with high levels of poverty, homophobia, racism, incarceration, and unemployment, Black MSM have no less than a 50/50 chance of getting HIV in a lifetime, according to the CDC.

Epidemiology of HIV/AIDS

Globally, around 38 million people are living with HIV. Despite vast improvements in treatment access, an estimated 1.5 million new infections and 680,000 HIV-related deaths occurred in 2020. Even so, that is over 50% fewer deaths and new infections than were reported at the height of the pandemic in 1997.

More than half of all people living with HIV today are in Africa. In some African countries, as many as one in four adults are living with HIV, according to data from the United Nations Programme on HIV/AIDS (UNAIDS).

In the United States, around 1.2 million people are currently living with HIV. Of those infections, an estimated 13% remain undiagnosed. Among those who have been diagnosed, only 65% have been able to achieve an undetectable viral load.

In 2020, just over 37,000 new HIV infections were reported in the United States and dependent areas, a drop of roughly 8% from 2015. Deaths have also been on the decline with a total of 5,115 deaths attributed to HIV-related complications.

Is There an HIV Vaccine?

Despite over 35 years of aggressive global research, scientists have yet to develop a vaccine able to effectively prevent or eradicate HIV. This is due in part to the fact that HIV mutates rapidly. Because of this, it is extremely challenging to develop a single vaccine able to target the multitude of strains and mutations.

Another challenge is that HIV quickly imbeds itself in tissues throughout the body, called latent reservoirs, soon after infection. Rather than multiplying, these viruses lay in hiding, largely unseen by the immune system.

Even if a vaccine were able to eradicate HIV in the bloodstream, these "hidden" viruses can spontaneously reactivate and start infection anew.

Faced with these setbacks, many scientists have shifted their focus to developing therapeutic vaccines designed to improve the body's immune response to HIV in someone who already has HIV.

Is There a Cure?

In 2008, scientists reported that Timothy Ray Brown, an American living in Berlin, was effectively "cured" of HIV following an experimental stem cell transplant. Despite the promise of a cure, the procedure proved highly risky, and subsequent attempts to repeat the results were either mixed or failed.

To date, only three other people have been declared "cured" of HIV. Even so, the insights gained from Brown and the others provided a general template for HIV cure research.

Today, scientists are largely focused on a "kick-kill" strategy. This involves designing medications able to "kick" HIV out of its hidden reservoirs, followed by drugs, vaccines, or immunotherapies that can effectively "kill" the newly released viruses. Research is ongoing.

Other scientists are focused on developing a "functional cure" for HIV. This is a vaccine that doesn't eradicate HIV but instead prevents it from progressing without the need for antiretroviral drugs.


HIV is a virus that causes disease by progressively killing immune cells, leaving the body vulnerable to opportunistic infections (OIs). If left untreated, HIV can progress to AIDS.

AIDS is the most advanced stage of the disease in which the immune system is compromised and unable to fight an ever-widening range of potentially life-threatening opportunistic infections.

HIV is diagnosed with highly accurate blood- and saliva-based tests, some of which can return results in a little as 20 minutes. If a positive result is received, medications called antiretrovirals are prescribed to can stop the virus from replicating.

The aim of HIV therapy is to achieve and sustain an undetectable viral load; this slows the progression of the disease and reduces the odds of infecting others to zero. There are currently more than two dozen different antiretroviral agents used in combination to treat HIV.

The same drugs can be used to reduce the risk of infection in someone without HIV (pre-exposure prophylaxis, or PrEP) or to avert infection in someone accidentally exposed to the virus (post-exposure prophylaxis, or PEP.)

Antiretrovirals do not cure HIV but keep it in check so that you can live a long, healthy life. If treatment is started early, a person can expect to live a near-normal life expectancy. Even so, of the 1.2 million people living with HIV in the United States, only 65% are able to achieve and sustain an undetectable viral load.

A Word From Verywell

HIV is not the same disease that it was 40 or even 20 years ago. Today, it is considered a chronic manageable condition in which people can enjoy a long and healthy life, plan for the future, and even have kids.

But, to do so, you need to be treated. This involves taking your medications every day as prescribed, seeing your healthcare provider, and getting routine blood tests performed as scheduled. For some, this can be difficult, particularly if you lack insurance, have an alcohol or substance abuse problem. or live with the fear of disclosure, stigma, or discrimination.

If faced with these concerns, it is important to share them with your healthcare provider who can refer to you people who can help (including counselors, social workers, and financial assistance advisors).

Frequently Asked Questions

  • What are the 4 stages of HIV?

    The stages of HIV can be broadly categorized by a person's CD4 count which serves as an indicator of disease progression:

    • Stage 1: Infection (CD4 count of 500 cells per cubic millimeters or more)
    • Stage 2: Asymptomatic (CD4 count of 350-499 cells per cubic millimeters)
    • Stage 3: Symptomatic (CD4 count of 200-349 cells per cubic millimeters)
    • Stage 4: AIDS (CD4 count under 200 cells per cubic millimeters)
  • What is the difference between HIV and AIDS?

    HIV is a virus that kills immune cells and leaves the body vulnerable to opportunistic infections. AIDS is the most advanced stage of HIV in which the immune system is compromised and unable to fight an ever-widening range of potentially life-threatening opportunistic infections.

  • How does HIV turn into AIDS?

    If left untreated, HIV can progress to AIDS in about eight to 10 years. Some people progress more quickly. On the other hand, a rare group of individuals, called elite controllers, appear resistant to disease progression and may never progress to AIDS.

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By James Myhre & Dennis Sifris, MD
Dennis Sifris, MD, is an HIV specialist and Medical Director of LifeSense Disease Management. James Myhre is an American journalist and HIV educator.