In the U.S., there's a good chance you could go a long time without hearing anything about HIV. Many schools aren't required to teach sexual education -- and of those that do, they're not required to teach accurate information. As a result, any knowledge you have about HIV might be solely from television or Google, both of which can unfortunately lead to you believing incorrect, and even harmful, information.
The reality is that HIV is complex. Yes, it's a virus that can cause biological illness, but it also has social and cultural origins -- as well as social and cultural impacts. When people talk about HIV, it's hard to talk about any one of these aspects without bringing up all of them. Here's a primer on all these different aspects of HIV and how they all fit together.
OK, What Exactly Is HIV?
HIV stands for human immunodeficiency virus. HIV has only one job: to make more HIV. When it enters a person's bloodstream, HIV hunts down a person's immune cells (called "T cells" or "CD4 cells") and injects its own genetic code into them. It hijacks these cells, first turning them into factories that make more copies of the virus, and then eventually killing those cells.
While these HIV-hijacked immune cells are busy making more copies of the virus, they can't do their primary job, which is defending your body from other viruses, bacteria, and infections that can cause illness -- and that a fully functioning immune system can usually beat on its own. That's why, in the early days of the epidemic, so many people with HIV succumbed to illnesses: Their immune systems were weakened by HIV until they could no longer fight off other illnesses.
How Do You Get HIV?
In order for HIV to go from one person to another, two things need to come into contact with each other:
- a bodily fluid that contains live HIV
- direct access to a person's bloodstream (sometimes called a "port of entry")

Common entry points into a person's bloodstream include:
- an unusual opening in the skin, like a cut or a puncture wound
- a mucous membrane, like the vagina or anus
These body fluids potentially contain infectious amounts of HIV:
- Blood
- Breast milk
- Presemen (a.k.a. precum)
- Rectal fluid
- Semen
- Vaginal fluid
This means you can potentially get HIV through:
- Anal sex (bottoming may be more of a risk than topping)
- Injecting drugs with shared needles or other equipment used to share drugs, known as "works"
- Vaginal sex
Infectious levels of HIV are not found in these fluids:
- Saliva
- Tears
- Urine
This means you cannot get HIV from:
- Kissing
- Mosquitoes
- Skin-to-skin contact, including a massage
- Sharing food or water
- Toilet seats
If someome living with HIV is on successful HIV treatment, this reduces the virus in their bloodstream to such a low level that they essentially can't transmit it to their sexual partners who are HIV negative.
Divide fact from fiction when it comes to HIV transmission. Get all the info here!
Read MoreWhat's the Difference Between HIV (Human Immunodeficiency Virus) and AIDS (Acquired Immunodeficiency Syndrome)?
People often use the terms HIV and AIDS interchangeably, but they are two different things!
- HIV is the name of a virus. When you are diagnosed as HIV positive, it means that there are copies of the virus in your bloodstream, indicating that HIV has taken control of some of your immune cells.
- AIDS is the name of the syndrome a person develops after HIV has so severely weakened their immune system that they're at risk for developing illnesses a healthy immune system would typically fight off.
- HIV is the only cause of AIDS.
- It usually takes many years of living with HIV and not taking HIV medications to develop AIDS.
In the early years of the HIV epidemic, most people living with HIV eventually developed AIDS -- and AIDS was often considered a death sentence. Today, once a person receives an AIDS diagnosis, they can take medication and get better, but because of how medical definitions work, the official diagnosis of AIDS remains.
AIDS -- which is short for acquired immunodeficiency syndrome -- is a very specific medical definition. To be considered as having AIDS, one of these two things must be true:
- Your CD4 count is below 200 cells/mm3. CD4 cells are part of the body's immune system. They're a type of immune cell called a T cell, and they're responsible for fighting off infections in your bloodstream. A CD4 count is a test that looks at the number of CD4 cells in your blood.
- You develop an "AIDS-defining condition," also called an opportunistic infection. This is one of about two dozen specific illnesses (including several cancers and bacterial, fungal, or viral infections) that can be fatal for people with a weakened immune system.
During the 1980s and 1990s, when HIV first became a huge health scare, AIDS was considered the final or end stage of HIV infection. But that was during a time when effective HIV treatment was still being developed. These days, HIV medications can -- and often do -- raise even some of the lowest CD4 counts back above 200, and can help the body restore the health of its immune system.
What Are the Symptoms of HIV?
There's no single, reliable sign or symptom of HIV infection. This is why the only trustworthy way to know whether you have HIV is to get an HIV test.
The symptoms a person with HIV might experience depend on how long they've been living with the virus, and whether or not they're on treatment. There are three major stages of HIV infection:
- acute infection (a.k.a. primary infection)
- chronic infection
- advanced HIV disease (AIDS)
Acute Infection
Also called primary infection, this phase typically occurs a few days to a few weeks after a person is exposed to HIV.
The most commom symptoms of acute HIV infection may be hard to tell apart from the flu, and might include any of the following:
- Fatigue (feeling tired or sapped of energy)
- Fever
- Mouth sores
- Muscle aches
- Night sweats
- Skin rashes
- Sore throat
- Swollen lymph nodes
If a person feels any symptoms from acute HIV infection, they usually go away by themselves within a few days or weeks -- about the same amount of time it takes to get over a cold or the flu.
It's also important to remember that plenty of people go through this acute stage of HIV exposure without feeling any symptoms at all.
Chronic Infection
This phase begins after the acute infection period ends. Chronic infection can last up to a decade or more if a person doesn't begin HIV treatment, and indefinitely if they are taking HIV medications.
A person may experience no symptoms during the chronic HIV infection phase. This is because HIV harms the immune system slowly, degrading it over a span of many years. If left untreated, the virus will continue to take over and destroy immune cells, turning them into HIV factories. When a person begins HIV treatment, the medications stop HIV from making copies of itself. This allows the immune system to recover -- or, if a person begins treatment early enough after exposure, to avoid most of the damage HIV can cause.
A person living with HIV who is on treatment can remain in the chronic stage indefinitely. In fact, thanks to HIV medicactions, many people living with HIV now live a lifespan similar to people who are not living with HIV.
Advanced HIV Disease
When people living with HIV go a long time without HIV treatment -- usually 10 years or more -- they'll usually enter the advanced infection phase, which can be life-threatening. This is the stage when a person is diagnosed with AIDS.
Symptoms of advanced HIV disease vary widely, because HIV itself isn't usually what causes the symptoms. Instead, those symptoms are caused by some other infection or disease that has taken root in the body because the immune system can no longer protect it.
During the worst years of the AIDS epidemic in the U.S. (in the 1980s and first half of the 1990s), people with advanced HIV disease experienced common symptoms and conditions such as:
• Kaposi's sarcoma, a type of cancer caused by a virus that can affect the skin, stomach, and lungs • Meningitis, a swelling around the brain caused by viruses, bacteria, or fungi • Thrush (a.k.a. candidiasis), a fungal infection of the mouth and throat that makes it painful to swallow • Wasting syndrome, in which people lose more than 10% of their body weight
Back in the 1980s and 1990s, AIDS was a very common and fatal syndrome. There were few treatments; the medications that existed involved taking up to 20 pills a day, and many had serious side effects. Today, a person living with HIV can be on treatment that only involves taking one pill a day, with few (if any) side effects, that keeps their immune system healthy for decades.
HIV/AIDS symptoms can affect your entire body and change from day to day. Learn more about which symptoms to watch out for.
Read MoreWho Gets HIV?
Truth is, anyone can get HIV -- a friend, a cousin, a colleague, or a partner. Regardless of a person's physical characteristics or identity, to transmit HIV, there only needs to be a fluid that contains HIV and access to a sexual partner's bloodstream.
In the U.S., HIV is still often thought of as a virus that mostly affects gay people. While it's true that most new cases of HIV occur among gay men, HIV isn't a "gay disease." Instead, the virus tends to thrive wherever discrimination and poverty are at their highest -- and where access to safe housing and good health care is at its lowest.
In the U.S., the groups most heavily impacted by HIV are:
- Transgender women
- Gay men
- Black people
- Latinx people
- Other people of color, including Native American/indigenous people
- People living with disabilities
- People living in southeastern states
Racism and other inequalities put people of color, especially Black people living in the southeastern U.S., at a much higher-than-average risk for HIV. While it's easy to say that a person's health is their own responsibility, there are often many factors at play. In fact, a person's risk for various illnesses -- including HIV -- is based in part simply on whether they're born in an impoverished zip code.
Worldwide, if you want to find the highest rates of HIV, look in areas that are struggling to deal with legacies of colonialism, racism, and other societal instability. Some of the highest HIV rates in the world are among people living in countries that were once colonized and are still underdeveloped, including much of Africa and South Asia.
Your race, sexuality, gender identity, country of origin, and any other personal identities or characteristics do not somehow mean you'll automatically get HIV. However, anyone with a marginalized identity may be at increased risk for HIV infection because of the many unfair health care biases in our world.

Where Did HIV Come From?
The short answer is: We're not certain how the HIV epidemic started.
The longer answer is: When it comes to where, when, and how HIV evolved into a virus that infected many millions of humans, we've learned a lot -- but there's a lot more we have yet to learn. In the meantime, going back to the earliest days of the HIV epidemic, there's been a lot of misinformation about how it all started. Many of those myths are still making the rounds today; all they do is worsen HIV stigma and create bigotry and discrimination against entire groups of people who don't deserve it.
Here's a few of the things we know pretty confidently about the origins of HIV: HIV evolved from another virus, SIV, which is short for simian immunodeficiency virus. SIV has existed in apes and monkeys for a very long time -- potentially tens of thousands of years, if not longer. It appears to be generally harmless to these primates, at least in the form we see today.
Humans can't get SIV -- it's a primate-only virus. But at some point, a strain of SIV mutated to infect people, and HIV was born. Scientists believe this has happened more than once, leading to at least two different strains of HIV, which we call HIV-1 and HIV-2. HIV-1 is by far the most common strain worldwide, while HIV-2 mostly appears in western Africa.
We don't know for certain when or where HIV made the leap into humans, although some of the most common theories today -- those that are most heavily backed by reputable science -- suggest that it happened in Africa in the early 20th century. We also don't know exactly how HIV first infected people, though there are plenty of unproven (and potentially harmful) ideas, including the hunting/butchering of monkeys or contaminated needles from vaccination campaigns.
Every viral epidemic starts somewhere. There are countless viruses in the world, and they're constantly evolving and mutating. Sometimes, those things happen in way that leads the virus to infect, and even kill, large numbers of people. HIV, it's turned out, has been one of those viruses. But that fact doesn't mean that the location where this epidemic happened to start deserves to be blamed for it -- or that any of the people who have been caught up in HIV's growth from a local outbreak to a decades-long global pandemic deserve special blame, either.
How Can I Prevent HIV?
If you are HIV negative and want to know how to stay negative, you have quite a few options.
The first thing you should know is that if you are having sex with someone living with HIV who is on medication and has an undetectable viral load, there is no risk of you acquiring the virus. There are two commonly used terms for this: "undetectable equals untransmittable" (or U=U for short) and "treatment as prevention."
In addition to that fact, people who are HIV negative also have options under their control that can empower them to stay HIV negative. Since HIV needs access to the bloodstream and bodily fluids containing the virus in order for infection to occur, most methods of protection break down into three categories:
- barrier protection
- biomedical prevention
- syringe exchange (or harm reduction)
Barrier Protection
Barrier protection puts a physical barrier between a person and a fluid containing HIV. The most popular methods include insertive condoms and receptive condoms.
- Insertive condoms are worn by insertive partners -- for example, a person who puts their penis into another person's anus or vagina.
- Receptive partners can wear receptive condoms in their anus or vagina.
Biomedical Prevention
While barriers make sure people don't come into contact with fluid containing HIV, biomedical prevention stops HIV from gaining a foothold in a person's body. There are two types of biomedical intervention: PrEP and PEP.
- PrEP, short for pre-exposure prophylaxis, is a plan that involves a person who is confirmed to be HIV negative taking a prescription medication to prevent exposure to HIV. It can be taken daily or in an "on-demand" schedule. At the moment, there are two different medications that have been approved in the U.S. for use as PrEP. Other types will be available in the future.
- PEP, short for post-exposure prophylaxis, is a month-long course of prescription HIV medications meant to prevent infection. If you think you have been exposed to HIV through sex, for example, you can begin PEP within 72 hours after the act.
Syringe Exchange
If you inject drugs, several states in the U.S. have programs where you can exchange used needles and syringes for fresh ones to reduce the risk of HIV transmission.
How Does HIV Testing Work?
The only way to learn for sure whether you're HIV positive or HIV negative is by getting an HIV test. In most of the U.S., it's about as easy to get an HIV test as it is to get a pregnancy test.
HIV testing is recommended as a routine part of health care for everyone in the U.S. between age 13 and age 64. More frequent testing (at least once a year, if not more) is recommended for people who are sexually active (regardless of whether it's anal or vaginal sex, or whether you're giving or receiving), especially if it's with multiple partners. Ditto for people who share injection drug equipment with anyone else.
There are three main types of HIV tests:
- At-home HIV tests. These are kits you can order online or pick up at a local pharmacy. Using a tiny sample of saliva or blood, they'll give you a preliminary test result -- if it's positive, you'll want to follow up with a health care provider for a confirmatory test. The typical cost is around $30 to $45.
- Rapid HIV tests. These are saliva or blood tests that a health care provider or other certified tester can give you. They provide a preliminary result in less than 20 minutes -- and some can be as quick as five minutes or less. If a rapid test is positive, your will need to get a full blood test to confirm the result.
- Confirmatory HIV tests. All HIV tests are accurate, but confirmatory tests do the best job at rooting out "false positives," which can happen rarely with at-home and rapid tests. The gold standard is called the "4th generation HIV test." A health care provider will take a sample of your blood and send it to a lab for in-depth testing; results typically take a few days to come back, sometimes longer, but will provide you with the most reliable result.
If you were very recently exposed to HIV -- as in, within the past couple of weeks -- older HIV tests may not be able to spot your infection. That's because it takes several days for the virus to make its way through your immune system and begin to create new copies of itself -- and weeks or months for your body to begin developing its own antibodies to fight off the HIV. (Some HIV tests work by detecting the virus itself, while others work by detecting the HIV antibodies your body creates.)
If you're concerned that a specific event happened to put you at risk for HIV, experts recommend that you:
- Talk to a health care provider immediately -- within 72 hours, if possible! -- about the possibility of starting PEP, or post-exposure prophylaxis. PEP can prevent an HIV exposure from becoming an infection.
- Wait to get tested for HIV until it's been more than two weeks since the risky event.
- Talk to a health care provider about whether an HIV prevention prescription -- also known as PrEP, or pre-exposure prophylaxis -- might be right for you.
Is There a Cure for HIV?
No, there is no cure. But thanks to science, people who are living with HIV often live long, healthy lives.
There is an extremely small number of cases where a person with HIV was cured of their infection with a type of bone marrow transplant. But these cases haven't been replicated on a large scale: The procedures are extremely difficult to do, and they're potentially deadly.
Meanwhile, researchers across the world are exploring a number of different potential ways to cure HIV more safely and reliably. But we're probably still many years away from having a cure.
Many HIV activists also feel that, even if there is a cure, there may be unequal access to it -- as there currently is with the cure for hepatitis C.
Will HIV Affect How I Live My Daily Life?
Living with HIV can have serious consequences for your body, but those physical effects can be prevented or treated by taking medication prescribed by a health care professional. That takes care of your body -- but what about your mental health and well-being?
While the medical community has worked hard to make HIV a manageable, chronic illness, our society still has a long way to go in eradicating HIV stigma and making the lives of people living with HIV easier.
HIV stigma is a term that refers to the negative and unfounded ideas about HIV that people have due to myths, misinformation, and outdated attitudes associated with the illness. Here are some examples of stigma:
- Treating someone with HIV differently than you would treat someone who is HIV negative.
- Using the word "clean" to denote being HIV negative.
- Believing all gay people have HIV.
- Believing that having HIV makes you less worthy or desirable than another person.
When a person adopts these ideas, they can in turn create shame and fear for people living with HIV, or what we might call internalized HIV stigma. HIV stigma can have terrible consequences. It can deter people from getting tested in the first place. It can lead people to avoid health care or to receive worse health care than they deserve, resulting in poorer physical and mental health. People with HIV also face disproportionate levels of intimate partner violence because of their status.
When a person acts out their stigma against someone living with HIV, it can lead to discrimination. In the U.S., there are laws relating to HIV -- some that help with discrimination, but some that hurt.
Helpful: HIV is a protected health status, and an employer cannot fire someone for living with HIV.
Hurtful: As of 2018, 26 states have laws that make HIV exposure a crime. While there have been legislative victories in some states, including Iowa and Colorado, the reality is that many states still prosecute people with HIV, even in cases where there was no HIV transmission.
Beyond these issues, people living with HIV have a lot to manage in order to stay healthy and happy. But with a clear plan, access to good health care, successful HIV treatment, and a strong support network, the virus can become just another fact of life -- a life that doesn't have to be one day shorter because of their HIV status.
- Medical Definition of AIDS: AIDSinfo. (n.d.). "HIV/AIDS Glossary: Acquired Immunodeficiency Syndrome (AIDS)." aidsinfo.nih.gov/understanding-hiv-aids/glossary/3/acquired-immunodeficiency-syndrome
- AIDS-Defining Conditions: U.S. Department of Veterans Affairs. (n.d.). "AIDS-defining illnesses." hiv.va.gov/patient/diagnosis/OI-AIDS-defining-illnesses.asp
- Stages of HIV: AIDSinfo. (2019). "The Stages of HIV Infection." aidsinfo.nih.gov/understanding-hiv-aids/fact-sheets/19/46/the-stages-of-hiv-infection
- HIV Symptoms: HIV.gov. (2019). "Symptoms of HIV." hiv.gov/hiv-basics/overview/about-hiv-and-aids/symptoms-of-hiv
- HIV Origins -- Some Current Theories: Nature Research. (2018). "Origin story." nature.com/articles/d42859-018-00008-6
- HIV Origins -- Myths and Assumptions: American Journal of Public Health. (2015). "Rumors and Realities: Making Sense of HIV/AIDS Conspiracy Narratives and Contemporary Legends." doi.org/10.2105/AJPH.2014.302284
- HIV Testing: Centers for Disease Control and Prevention. (2019). "HIV: Testing." cdc.gov/hiv/basics/testing.html
- HIV Test Types: U.S. Food and Drug Administration. (2019). "Complete List of Donor Screening Assays for Infectious Agents and HIV Diagnostic Assays." fda.gov/vaccines-blood-biologics/complete-list-donor-screening-assays-infectious-agents-and-hiv-diagnostic-assays
- Who Gets HIV: Centers for Disease Control and Prevention. (2018). "HIV Surveillance Report, 2017." cdc.gov/hiv/pdf/library/reports/surveillance/cdc-hiv-surveillance-report-2017-vol-29.pdf
- HIV Stigma: Centers for Disease Control and Prevention. (2019). "Facts About HIV Stigma." cdc.gov/hiv/basics/hiv-stigma/index.html