UPDATE COMING We’re currently working to update this article. that a person living with HIV who is on regular antiretroviral therapy that reduces the virus to undetectable levels in the blood is NOT able to transmit HIV to a partner during sex. This page will be updated soon to reflect the medical consensus that “Undetectable = Untransmittable.”

It can be easy to confuse HIV and AIDS. They are different diagnoses, but they do go hand-in-hand and are often used interchangeably to describe a particular disease. HIV is a virus that can lead to a condition called AIDS.

At one time in history, a diagnosis of HIV or AIDS was considered a death sentence. Thanks to research and the development of new treatments, people diagnosed with HIV and AIDS today are living long, productive lives.

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HIV is a virus

HIV is a virus that can lead to infection. It stands for human immunodeficiency virus. The name describes the virus: it infects humans only and it attacks the immune system, rendering it deficient and unable to work as effectively as it should.

Unlike many other viruses, our immune systems are unable to attack and completely clear HIV from the body. No one yet understands why, but medications can control HIV very successfully.

AIDS is a condition

HIV is a virus that may cause an infection, but AIDS is a condition or a syndrome. Being infected with HIV can lead to the development of AIDS, which stands for acquired immunodeficiency syndrome.

AIDS develops when HIV has caused serious damage to the immune system. It is a complex condition with symptoms that vary from person to person. Symptoms of AIDS are related to the infections a person develops as a result of having a damaged immune system that can’t fight infections as well. These infections may include tuberculosis, pneumonia, certain types of cancer, and other infections.

HIV without AIDS

HIV is a virus and AIDS is the condition it may cause. You can have an HIV infection without acquiring AIDS. In fact, many people with HIV live for years without developing AIDS. Thanks to advances in treatment, you can live longer than ever before with an HIV infection.

While you can have an HIV infection without having AIDS, anyone diagnosed with AIDS already necessarily has HIV. Because there is no cure, the HIV infection never goes away, even if AIDS never develops.

HIV can be transmitted from person to person

HIV is a virus, which means that like other viruses, it can be transmitted between people. This is how infection spreads. AIDS, on the other hand, is a condition that is acquired only after a person has contracted the HIV infection.

The HIV virus is transmitted from one person to another through the exchange of bodily fluids. Most commonly, infection is transmitted through unprotected sex or through using contaminated needles. Less commonly, one can become infected through a tainted blood transfusion or a mother can pass the infection to her child during pregnancy.

HIV does not always produce symptoms

HIV usually causes flu-like symptoms about two to four weeks after infection. This period of time is short and is called acute infection. The immune system brings the infection under control, leading to the latency period.

The immune system cannot completely eliminate HIV, but it can control it for a long time. During this latent period, which can last for years, an infected person may experience no symptoms at all. Once AIDS has developed, however, the patient will experience many symptoms of the condition.

HIV infection can be diagnosed by a simple test

When infected with HIV, your immune system produces antibodies against the virus. A blood or saliva test can detect those antibodies and determine if you’ve been infected with HIV. This test may be effective only several weeks after infection, though.

Another test looks for antigens, which are proteins produced by the virus. This test can detect HIV just days after infection. Both tests are accurate and easy to administer.

AIDS diagnosis is more complicated

AIDS is the final stage of the HIV infection. There are a few factors that determine when a person’s diagnosis has crossed from HIV latency to AIDS.

Because HIV destroys immune cells called CD4 cells, one part of the AIDS diagnosis contains a count of those cells. A person without HIV can have anywhere from 500 to 1,200 CD4 cells. When the cells have dropped to 200, a person with HIV is considered to have AIDS.

Another factor signaling the AIDS virus is the presence of opportunistic infections. Opportunistic infections are diseases caused by viruses, fungi, or bacteria that would not make a person with a fully functioning immune system sick. This, too, would help determine an AIDS diagnosis.

Treatment and life expectancy

Once HIV has developed into AIDS, life expectancy drops significantly. It’s difficult to repair the damage to the immune system at this point. Infections and other conditions, such as cancers, resulting from severe immune impairment are common. These infections and other complications are what become fatal for a person with AIDS.

With today’s treatments for the HIV infection, however, someone can live with the virus for years, and even decades before AIDS develops. Even though you can lead a normal and healthy life while undergoing HIV treatment, it’s important to understand that you can still pass the infection to someone else.