What Is HIV?

Table of Contents

HIV (human immunodeficiency virus) is a virus that attacks the immune system. If left untreated, it can lead to AIDS (acquired immunodeficiency syndrome). But thanks to major advances in medicine, HIV is no longer a death sentence — and many people live long, full, and healthy lives.
HIV spreads through certain body fluids — like blood, semen, vaginal fluids, rectal fluids, and breast milk. It’s commonly transmitted through sex, sharing needles, or from mother to child during birth or breastfeeding.

Routine HIV testing is one of the most important tools we have in sexual health. It helps people get diagnosed early, start treatment, and avoid passing the virus to others. Today, people who test positive and start treatment early can have a life expectancy close to someone without HIV.

You can’t tell by looking who has HIV. And with early treatment, you can’t pass it on sexually if your virus is undetectable (see U=U below).

Learn more from HIV.gov
See CDC HIV Basics

Quick Facts About HIV

HIV, or human immunodeficiency virus, is most commonly transmitted through sex or needle sharing, but it can also be passed during birth or breastfeeding. It affects more than 1.2 million people in the U.S., and many don’t know they have it.

Most people don’t show symptoms at first, but left untreated, HIV can weaken the immune system and lead to serious complications. Today, HIV is highly manageable with daily treatment — and people who stay on therapy can live long, healthy lives without ever developing AIDS.

Testing is available through rapid swabs, lab-based blood tests, and home kits. Treatment involves antiretroviral therapy (ART), which can make the virus undetectable — and untransmittable.

What Are Symptoms of HIV?

HIV doesn’t always show symptoms — and many people don’t know they have it until they get tested. But when symptoms do appear, they tend to show up in stages.

Early symptoms (2 to 4 weeks after infection):

Some people get flu-like symptoms called acute retroviral syndrome (ARS):

  • Fever
  • Fatigue
  • Swollen lymph nodes
  • Rash
  • Sore throat
  • Muscle aches

These symptoms often go away in a week or two, and then the virus quietly multiplies in the body for years.

Chronic phase (no symptoms):

After the initial illness, HIV may not cause any noticeable symptoms for years. But it’s still active and damaging the immune system.

Late-stage HIV/AIDS:

Without treatment, HIV progresses to AIDS — where the immune system is severely weakened. Symptoms may include:

  • Rapid weight loss
  • Frequent infections
  • Night sweats
  • Fatigue
  • Sores or lesions in the mouth or genitals

Regular testing helps catch HIV before it reaches this stage.

What Does HIV Look Like?

HIV isn’t something you can see. There are no visible sores or bumps. If anything, early symptoms may mimic the flu or mono — and then disappear.

In late-stage HIV/AIDS, people may develop visible signs like oral thrush, shingles, or skin lesions — but that’s rare with modern treatment.

The only way to know is to get tested.

Find testing locations near you

How Is HIV Transmitted?

HIV spreads through direct contact with certain bodily fluids from a person who has HIV — specifically:

  • Blood
  • Semen (cum) and pre-cum
  • Vaginal fluids
  • Rectal fluids
  • Breast milk

The most common ways people get HIV are:

  • Having anal or vaginal sex without a condom
  • Sharing needles or syringes
  • During childbirth or breastfeeding (mother to child)

HIV is not spread through saliva, sweat, tears, kissing, hugging, sharing food, or toilet seats.

Can HIV be prevented?

Yes. Prevention strategies include:

  • PrEP (pre-exposure prophylaxis): a once-daily pill or bimonthly injection for people at higher risk. When taken consistently, PrEP reduces the risk of getting HIV from sex by about 99%.
  • PEP (post-exposure prophylaxis): emergency medication taken within 72 hours of possible exposure
  • Condoms: still effective for reducing HIV and other STI risks
  • Regular testing and treatment: Knowing your status helps protect you and your partners

Learn about PrEP from CDC
Find PrEP providers near you

How Do You Test for HIV?

Getting tested for HIV is one of the most important things you can do for your health — and your partners’. Testing is quick, confidential, and widely available. Many clinics, health departments, and pharmacies offer both rapid and lab-based testing, and you can also find reliable home testing kits.

There are several kinds of HIV tests. Rapid tests use a finger prick or oral swab and give results in 20 minutes or less. More advanced lab-based tests, such as the fourth-generation antigen/antibody test, can detect HIV sooner after exposure. These tests look for both the virus itself and the body’s early immune response. If you want to test at home, there are FDA-approved kits available online or in stores, but they may be slightly less sensitive during the early window period.

The CDC recommends that everyone between the ages of 13 and 64 get tested for HIV at least once, and more often if you’re sexually active with new or multiple partners, starting PrEP, or sharing needles. Testing is especially important if you’ve had unprotected sex, if you or your partner have other STIs, or if you’re unsure of your partner’s status.

At Chekd, we don’t currently offer HIV testing ourselves, but we help you compare the best available testing options — including lab-based panels, at-home test kits, and local clinics. Whether you’re looking for convenience, affordability, or comprehensive screening, we guide you toward the right choice for your situation.

Remember: HIV testing is a normal part of staying on top of your health. And finding out your status is the first step to either peace of mind — or early access to life-saving treatment..

How Is HIV Treated?

There’s no cure for HIV yet, but the treatment we have today is incredibly effective. Most people take just one pill a day — and that’s enough to stop the virus from multiplying, protect the immune system, and prevent transmission.

Treatment for HIV is called antiretroviral therapy (ART). It works by reducing the amount of virus in your body — the “viral load” — to levels so low that blood tests can’t detect it. When this happens, you’re considered undetectable.

And here’s the life-changing truth: Undetectable = Untransmittable (U=U). That means if you’re on treatment and your viral load is undetectable, you can’t pass HIV to your partners through sex.

ART not only prevents transmission, it also keeps your immune system strong and stops HIV from progressing to AIDS. The sooner you start, the better your long-term health outcomes. And once you’re on treatment, staying on it becomes a simple, daily routine — like managing any other chronic condition.

Get treatment guidance from HIV.gov

Complications of HIV

Without treatment, HIV continues to damage the immune system over time. Eventually, it can progress to AIDS — the most advanced stage of HIV — when the body becomes highly vulnerable to serious infections, cancers, and other health problems.

This is when rare or so-called “opportunistic infections” can take hold, such as certain types of pneumonia, tuberculosis, or Kaposi sarcoma. The risk of cognitive decline, cardiovascular disease, and certain cancers also increases.

But here’s the hopeful reality: with early diagnosis and consistent treatment, most people never reach this stage. Modern medicine allows people with HIV to live long, full lives — and avoid the complications that once made HIV so devastating.

Outlook & Prognosis

The outlook for people with HIV has changed dramatically in the past 30 years. With early diagnosis and effective treatment, people with HIV can expect to live long, healthy lives.

Consistent care and medication are essential. So is mental health support, especially in navigating the social and emotional parts of living with a chronic condition.

Living With HIV

Living with HIV today means managing a chronic health condition — not living in fear. With treatment, most people with HIV are undetectable, feel healthy, and lead full, connected lives. That includes relationships, parenthood, careers, and travel.

One of the most powerful parts of living well with HIV is knowing you can’t transmit the virus sexually if you’re undetectable. That allows many people to reclaim intimacy and confidence in their dating lives.

Still, stigma remains. Some people feel isolated or anxious after diagnosis — which is why emotional support is just as important as medical care. You don’t have to go through it alone. Connecting with others, finding affirming care, and speaking openly (when and if you’re ready) can make a huge difference.

To get started or stay supported:

How to Tell Your Partner(s) You Have HIV

Telling someone you have HIV can feel scary — but it’s a powerful act of trust and care. And with modern treatment, the conversation is very different than it was in the past.

Try saying:

“I want to share something important with you. I’m living with HIV, but I’m on treatment, and my virus is undetectable — meaning I can’t pass it to anyone. I take my health seriously, and I wanted to be upfront with you.”

You can also explain:

  • What U=U means
  • That treatment works
  • That you’re sharing this because you value honesty and connection

There’s no one “right way” to disclose — but sharing your status can deepen trust, reduce fear, and protect both you and your partner.

Disclosure support: The Well Project

Last reviewed: May 2025
This content is regularly reviewed and updated to reflect the latest medical guidelines.

  • Caused by: Human immunodeficiency virus (HIV)
  • Spread through: Sex (anal or vaginal), shared needles, blood, birth, or breast milk
  • Symptoms: Often none at first; may include flu-like illness, fatigue, weight loss
  • Testing: Rapid test (oral or blood), lab test (antigen/antibody), home test kits
  • Treatment: Daily antiretroviral therapy (ART) controls the virus
  • Risk if untreated: Weakened immune system, opportunistic infections, progression to AIDS
  • How common: Over 1.2 million people live with HIV in the U.S. (CDC)

 

Frequently Asked Questions

Can I have HIV and not know it?

Yes. Many people with HIV have no symptoms for years, especially early on. That’s why regular testing is essential — it’s the only way to know your status.

How soon after exposure can HIV be detected?

It depends on the test. Rapid tests can usually detect HIV within 3–12 weeks, while lab-based fourth-generation tests may detect it as early as 2–4 weeks after exposure.

What’s the difference between HIV and AIDS?

HIV is the virus. AIDS is the most advanced stage of HIV infection, when the immune system is severely weakened. With treatment, most people with HIV never develop AIDS.

If I test positive, what happens next?

You’ll confirm the result with a follow-up test, and then start antiretroviral therapy (ART). Today, treatment is highly effective and easy to take — often just one pill a day.

Can I still have sex if I’m HIV positive?

Yes. If you’re on treatment and your viral load is undetectable, you cannot pass the virus to your partner through sex. This is known as U=U — undetectable = untransmittable.

What is PrEP and who should take it?

PrEP (pre-exposure prophylaxis) is a daily pill or bimonthly shot that prevents HIV. It’s recommended for people who have sex with partners whose HIV status is unknown or who are at higher risk.

What is PEP and when should I use it?

PEP (post-exposure prophylaxis) is a medication you take after a possible HIV exposure — ideally within 72 hours. It’s used in emergencies, like condom failure or sexual assault.

How do I talk to a new partner about HIV?

Be clear, honest, and informed. Let them know if you’re undetectable, on PrEP, or recently tested. You can say, “I get tested regularly and take precautions. Here’s what I do to protect us.”

Is it legal to not tell someone you have HIV?

Laws vary by state, but in many places, people living with HIV must disclose their status before sex. These laws are evolving. Learn more at HIV Justice Network.

Will HIV affect my ability to have children?

No. With the right medical care, people living with HIV can have children without passing on the virus. Treatment prevents transmission to partners and babies.

Can I get HIV from oral sex?

It’s possible, but the risk is lower than with vaginal or anal sex. Using condoms or dental dams further reduces risk.

Does insurance cover HIV testing and PrEP?

Yes. Most insurance plans — including Medicaid — cover HIV testing and PrEP. Many programs also offer it for free or at low cost.

What if I test positive and feel ashamed or afraid?

You’re not alone. HIV stigma is real, but support is available. With treatment, HIV is manageable. Connecting with others can help you feel empowered.

Is there a vaccine or cure for HIV?

There’s no cure yet, but research is ongoing. The best protection is regular testing, using protection, and considering PrEP if you’re at risk.

Where can I find help and support?

Check out resources like TheBody, HIV.gov, or local clinics. You can also call the CDC info line at 1-800-CDC-INFO for referrals.