WHAT IS HIV?
To understand what HIV is, let’s break it down:
Human – This particular virus can only infect human beings.
Immunodeficiency – HIV weakens your immune system by destroying important cells that fight disease and infection. A “deficient” immune system can’t protect you.
Virus – A virus can only reproduce itself by taking over a cell in the body of its host.
Human Immunodeficiency Virus is a lot like other viruses, including those that cause the “flu” or the common cold. But there is an important difference – over time, your immune system can clear most viruses out of your body. That isn’t the case with HIV – the human immune system can’t seem to get rid of it. Scientists are still trying to figure out why.
We know that HIV can hide for long periods of time in the cells of your body and that it attacks a key part of your immune system – your T-cells or CD4 cells. Your body has to have these cells to fight infections and disease, but HIV invades them, uses them to make more copies of itself, and then destroys them.
Over time, HIV can destroy so many of your CD4 cells that your body can’t fight infections and diseases anymore. When that happens, HIV infection can lead to AIDS.
WHAT IS AIDS?
To understand what AIDS is, let’s break it down:
Acquired – AIDS is not something you inherit from your parents. You acquire AIDS after birth.
Immuno – Your body’s immune system includes all the organs and cells that work to fight off infection or disease.
Deficiency – You get AIDS when your immune system is “deficient,” or isn’t working the way it should.
Syndrome – A syndrome is a collection of symptoms and signs of disease. AIDS is a syndrome, rather than a single disease, because it is a complex illness with a wide range of complications and symptoms.
Acquired Immunodeficiency Syndrome is the final stage of HIV infection. People at this stage of HIV disease have badly damaged immune systems, which put them at risk for opportunistic infections (OIs).
You will be diagnosed with AIDS if you have one or more specific OIs, certain cancers, or a very low number of CD4 cells. If you have AIDS, you will need medical intervention and treatment to prevent death.
For more information, see CDC’s Basic Information About HIV And AIDS.
HOW DO YOU GET HIV or AIDS?
HIV can be transmitted though
– Sexual contact
– Pregnancy, childbirth & breast feeding
– Injection drug use
– Occupational exposure
– Blood transfusion / organ transplant
How do you get HIV?
HIV is found in specific human body fluids. If any of those fluids enter your body, you can become infected with HIV.
HIV lives and reproduces in blood and other body fluids. We know that the following fluids can contain high levels of HIV:
– Semen (cum)
– Pre-seminal fluid (pre-cum)
– Breast milk
– Vaginal fluids
– Rectal (anal) mucous
Other body fluids and waste products—like feces, nasal fluid, saliva, sweat, tears, urine, or vomit—don’t contain enough HIV to infect you, unless they have blood mixed in them and you have significant and direct contact with them.
Healthcare workers may be exposed to some other body fluids with high concentrations of HIV, including: amniotic fluid, cerebrospinal fluid and synovial fluid.
How do you get AIDS?
AIDS is the late stage of HIV infection, when a person’s immune system is severely damaged and has difficulty fighting diseases and certain cancers. Before the development of certain medications, people with HIV could progress to AIDS in just a few years. Currently, people can live much longer – even decades – with HIV before they develop AIDS. This is because of “highly active” combinations of medications that were introduced in the mid 1990s. Read more about how HIV causes AIDS.
SIGNS & SYMPTOMS
Early stage of HIV: Symptoms
Within 2-4 weeks after HIV infection, many, but not all, people experience flu-like symptoms, often described as the “worst flu ever.” This is called “acute retroviral syndrome” (ARS) or “primary HIV infection,” and it’s the body’s natural response to the HIV infection.
Symptoms can include:
– Fever (this is the most common symptom)
– Swollen Glands
– Sore Throat
– Muscle and Joint Aches and Pains
These symptoms can last anywhere from a few days to several weeks. However, you should not assume you have HIV if you have any of these symptoms. Each of these symptoms can be caused by other illnesses. Conversely, not everyone who is infected with HIV develops ARS. Many people who are infected with HIV do not have any symptoms at all for 10 years or more.
You cannot rely on symptoms to know whether you have HIV. The only way to know for sure if you are infected with HIV is to get tested. If you think you have recently been exposed to HIV—if you have had oral, vaginal or anal sex without a condom with a known HIV positive person or a partner whose HIV status you do not know or shared needles to inject drugs—get an HIV test. Traditional HIV tests detect HIV antibodies. But during this early stage your body is not yet producing these antibodies. A new HIV test was approved in 2013 that can detect the presence of HIV in your body during this early stage of infection. So no matter where you get tested, it is very important to let your provider know that you may have been recently infected with HIV and you would like to be tested for acute HIV. Use the HIV/AIDS Testing and Services Locator to find a HIV testing site near you.
The clinical latency stage
After the early stage of HIV infection, the disease moves into a stage called the “clinical latency” stage. “Latency” means a period where a virus is living or developing in a person without producing symptoms. During the clinical latency stage, people who are infected with HIV experience no HIV-related symptoms, or only mild ones. (This stage is sometimes called “asymptomatic HIV infection” or “chronic HIV infection.”)
During the clinical latency stage, the HIV virus reproduces at very low levels, although it is still active. If you takeantiretroviral therapy (ART), you may live with clinical latency for several decades because treatment helps keep the virus in check. For people who are not on ART, this clinical latency stage lasts an average of 10 years, but some people may progress through this phase faster.
It is important to remember that people in this symptom-free period are still able to transmit HIV to others even if they are on ART, although ART greatly reduces the risk of transmission.
Again, the only way to know for sure if you are infected with HIV is to get tested. Tests are available that can detect the virus at this stage. Use the HIV/AIDS Testing and Services Locator to find a HIV testing site near you.
Progression to AIDS: Symptoms
If you have HIV and you are not taking HIV medication (antiretroviral therapy), eventually the HIV virus will weaken your body’s immune system. The onset of symptoms signals the transition from the clinical latency stage to AIDS (Acquired Immunodeficiency Syndrome).
During this late stage of HIV infection, people infected with HIV may have the following symptoms:
– 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
– PneumoniaRed, 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 be related to other illnesses. So, as noted above, the only way to know for sure if you are infected with HIV is to get tested.
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.
For more information, see the National Library of Medicine’s AIDS.