Overview Illustration - HIV

What Is Human Immunodeficiency Virus (HIV)?

HIV weakens your immune system by attacking your white blood cells. If untreated, HIV can progress into acquired immunodeficiency syndrome (AIDS).

Human immunodeficiency virus (HIV) attacks your body's immune system. The virus decreases your body's ability to fight infections by attacking your white blood cells. If untreated, HIV can progress into acquired immunodeficiency syndrome (AIDS). AIDS happens if your body has very few white blood cells, which leaves you vulnerable to severe illness and death.

The origins of HIV remain unknown. Some researchers believe the virus "jumped" from non-human primates to humans during the 20th century. In the United States, some of the first cases of HIV occurred during the 1980s. At that time, HIV primarily affected gay and bisexual men, which led to widespread stigma and violence against the LGBTQ+ community.

However, anyone can contract HIV. HIV spreads through unprotected sex, shared drug needles, or contact with blood. The virus may also spread from mother to her child during pregnancy, childbirth, or breastfeeding.

There's no cure for HIV. However, treatment can control your white blood cell count. Treatment can also prevent the spread of HIV. It's entirely possible to live a long, healthy life with HIV.

HIV Symptoms

HIV symptoms vary between people. Still, it's not uncommon to experience flu-like symptoms within two to four weeks after infection.

Symptoms include:

  • Fever
  • Chills
  • Fatigue
  • Sore throat
  • Swollen lymph nodes
  • Muscle aches
  • Night sweats
  • Rash
  • Canker sores

Those symptoms may last a few days or linger for a few weeks. Some people don't have any symptoms.

As HIV progresses, it's common not to have any symptoms. In contrast, if HIV progresses into AIDS, you will become vulnerable to severe illness and death. People with AIDS have little white blood cells that help protect them against infections. Without a strong immune system, their risk of opportunistic infections increases.

Opportunistic infections are severe illnesses that affect people with weak immune systems. Some common examples of opportunistic infections include pneumocystis pneumoniai and invasive cervical cancer. Pneumocystis pneumonia is a severe form of pneumonia.

AIDS symptoms include:

  • Weight loss
  • Fever that comes and goes
  • Swollen lymph nodes in the armpits, neck, or groin area
  • Diarrhea
  • Sores (commonly found on the mouth, genitals, or anal region)
  • Discolored skin
  • Memory loss
  • Depression
  • Infections
  • Neurological dysfunction

How Does HIV Spread?

HIV spreads through infected blood, semen, or vaginal secretions that enter your body. The virus commonly spreads through:

  • Anal sex: During anal sex, HIV spreads through semen, pre-seminal fluid, or rectal fluid. So, the receptive partner has a higher risk of HIV than the insertive partner. The thin tissue lining the rectum allows easy transmission of the virus. The insertive partner also carries some risk. The virus can spread through the urethra, foreskin, or open wounds on the penis.  
  • Vaginal sex: Vaginal sex carries less risk of HIV than anal sex. Still, the virus can spread through semen, pre-seminal fluid, vaginal fluid, or menstrual blood.  
  • Shared drug needles and syringes: Sharing drug paraphernalia increases your risk of contact with other people's blood.
  • Pregnancy, childbirth, and breastfeeding: HIV can spread from mother to fetus through the placenta during pregnancy. The fetus is further at-risk during childbirth. HIV can be spread through blood, amniotic fluid, and breast milk.

It's also important to know how you cannot get HIV, including:

  • Insect bites
  • Saliva, sweat, or tears
  • Hugging
  • Shaking hands
  • Using a public toilet
  • Closed-mouth kissing
  • Touching
  • Airborne

Risk Factors

Remember: Anyone can get HIV, regardless of gender, race, or sexual orientation. However, you're at higher risk if you:

  • Have unprotected sex (sex without a condom)
  • Have multiple sex partners
  • Use injectable drugs
  • Have a sexually transmitted infection (STI) or genital sores

How Is HIV Diagnosed?

HIV testing can be stressful. Still, early testing is essential if you've had recent exposure to the virus. If diagnosed early, HIV is highly treatable. Three different tests can check for HIV, including:

  • Antigen/antibody test: This test looks for antibodies your immune system has made to fight off HIV. It can also detect unique parts of the virus. Those are called antigens. An antigen/antibody test is the most common way to test for HIV. A healthcare provider will collect a blood sample from your finger or vein. 
  • Antibody test: This type of test only looks for antibodies. Antibody tests are available as rapid self-test. They check your saliva or blood and give you results within 20 minutes.
  • Nucleic acid test (NAT): This is a blood test that can detect the actual HIV virus. NAT can also measure how much of the virus is in your blood. However, the test is expensive. 

If your test is negative, that means you don't have HIV. Still, it's only safe to assume that if you haven't had any possible exposure within the past three months. These tests can only detect HIV 10–90 days after exposure. So, taking another test is vital if your possible exposure occurred less than 90 days ago. 

If your test is positive, consult a healthcare provider as soon as possible. They can do a follow-up test to confirm the result.

Stages of HIV

There are three stages of HIV, which include:

  • Stage 1: Stage 1 is also known as the "acute infection" stage. If you contract HIV, your immune system will attempt to fight the virus. During that time, you have a high viral load. A high amount of the virus in your blood makes you highly contagious.
  • Stage 2: Stage 2 is also known as "chronic HIV infection." As the virus advances, it spreads through your body. That occurs at lower levels than during Stage 1. Though, you can still infect others. HIV will eventually multiply throughout your body without any treatment, increasing your viral load. That can last over a decade.
  • AIDS: If HIV progresses to AIDS, the virus begins to break down your immune system significantly. That leaves you vulnerable to various illnesses. People with AIDS have an extremely high viral load and are very contagious. Without treatment, the life expectancy for people diagnosed with AIDS is three years.

In the United States, most HIV-positive people don't advance to AIDS. That's due to highly effective treatment.

Treatments for HIV

There is no cure for HIV. However, there are plenty of effective treatments. Treatments can keep HIV from progressing into AIDS. So, it's possible to live a healthy life with HIV.

You can decrease the risk of spreading the virus by reducing your viral load. Antiretroviral therapy (ART) reduces the amount of HIV in your blood. It involves a mix of several HIV medicines. The sooner your start ART, the better. 

Still, ART does not cure or eliminate the risk of HIV. So, it's essential to regularly take your medicines even after your viral load goes down and you don't have any symptoms. Missing a dose gives HIV a chance to spread throughout your body and weaken your immune system.

How To Prevent HIV

Much progress has been made to prevent the virus from spreading. Luckily, there are several ways you can stay safe. Those methods include:

  • Using condoms: They're the only form of birth control to protect you from HIV and other sexually transmitted infections.
  • Getting tested: Not just for HIV, but for all STIs. Having an STI raises your risk of getting infected with HIV. Ask your partner to get tested, too.
  • If you're HIV-positive, taking medicine as prescribed: ART can lower your viral to undetectable levels. If taken correctly, ART can minimize the risk of spreading the virus to others.
  • Not sharing needles and syringes: Only use sterile drug equipment, and talk to a healthcare provider, therapist, or someone else you trust about ways you can quit using drugs. Substance use can throw off your decision-making and steer you into other activities that may raise your risk of HIV.
  • Post-exposure prophylaxis (PEP): PEP is an emergency medicine you can take after potential exposure to HIV. You must begin PEP within 72 hours for it to be effective.
  • Pre-exposure prophylaxis (PrEP): PrEP is a preventative medicine. It can significantly lower your risk of HIV if you're at risk.
  • Taking precautions if you're pregnant: If you are HIV-positive and become pregnant, consult a healthcare provider about HIV treatment. They may advise giving HIV treatment to your infant for two to six weeks after childbirth. Together, those methods can lower the risk of spreading HIV to your fetus to less than 1%. Also, if you're at risk of contracting HIV (if your partner is HIV-positive), talk to a healthcare provider about PrEP to minimize your risk.

The more of these tips you follow, the lower your risk of HIV will be.

Comorbid Conditions

Some research suggests that about one-third of people with HIV have one comorbid condition. Some of the most common conditions that are comorbid with HIV include:

  • Hepatitis C (HCV): About 21% of people with HIV in the United States have HCV, a liver disorder. Like HIV, HCV spreads through blood. Both viruses share a significant risk factor: Sharing drug needles and syringes. Also, HIV may cause HCV to become a chronic condition.
  • Mental health disorders: Research has found that mental health disorders are 1.5 to eight times higher in people with HIV than others. Depression, substance abuse, and post-traumatic stress disorder (PTSD) are common.
  • Heart disease: Inflammation and a weakened immune system play a key role in the onset of heart disease in people with HIV.

Living With HIV

An HIV diagnosis can be scary. Luckily, most people with HIV in the United States live healthy lives thanks to highly effective medicines. 

However, since the first cases in the 1980s, there has been widespread fear and stigma surrounding the virus. If you have HIV, taking care of your physical and mental health is essential.

Here are some ways you can prioritize your well-being:

  • Consult a healthcare provider about establishing a treatment plan. 
  • Take your medicines as prescribed.
  • Visit a healthcare provider regularly. 
  • Find a support group, or talk to a mental health counselor. 
  • Eat healthily and regularly exercise. Taking care of your body can help boost your immune system. 
  • Get at least eight hours of restful sleep daily.
  • If you smoke, consider quitting. Smoking raises your risk of developing other chronic conditions that can weaken your immune system. 

A Quick Review

HIV weakens your body's immune system by attacking your white blood cells. The virus spreads through semen, blood, vaginal fluid, and rectal fluid. If untreated, HIV can progress into AIDS, which makes you vulnerable to severe illness and death.

In the United States, most people with HIV do not progress into AIDS thanks to a highly effective treatment regimen called ART. There are also PEP and PrEP medicines that can prevent HIV infection if you're at risk. 

Many people with HIV live long, healthy lives. Early testing and establishing a treatment regimen are essential if you think you have been exposed to the virus or are HIV-positive. 

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26 Sources
Health.com uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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