An Overview of HIV/AIDS

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HIV/AIDS is an acronym that often is used to refer to the advanced stage of illness, AIDS (acquired immunodeficiency syndrome), caused by infection with HIV, (human immunodeficiency virus). When AIDS first appeared in 1981, most cases were fatal. Once researchers determined that HIV was the cause of AIDS and how the virus spreads (primarily through sexual contact or exposure to infected blood), they were able to develop ways to test for the virus and also develop effective treatments for preventing the virus from replicating in the body—a protocol called antiretroviral therapy (ART).

With the exception of short-lived flu-like symptoms that tend to develop within a few weeks of infection, most people who are HIV positive and begin taking medication never become sick and go on to live otherwise long and healthy lives. In fact, testing positive for HIV is no longer a death sentence in developed parts of the world: Studies have found that patients who begin ART while the amount of virus in their bodies is relatively low have the same life expectancy of the general population.

HIV/AIDS By the Numbers

Since it was identified, HIV has been attributed to the deaths of over 30 million people worldwide. Globally, there are more than 35 million people living with HIV today, 69 percent of whom are in sub-Saharan Africa.

In the U.S., approximately 1.2 million people are infected with HIV, according to the U.S. Centers for Disease Control and Prevention (CDC). Of these, 20 percent to 25 percent are estimated to be undiagnosed.

Even so, AIDS is regarded as a rare disease in this country: Fewer than 200,000 people who are HIV-positive go on the develop AIDS.


The symptoms of HIV/AIDS can be roughly divided into two categories: symptoms that appear when the body is first infected (the initial or acute phase), and those that may occur after years if the virus isn't treated and the infection is allowed to progress to full-blown AIDS.

Initial Infection

Within a few weeks of entering the body, HIV will trigger flu-like symptoms and, in some cases, a few other tell-tale symptoms:

  • Fever
  • Chills
  • Headache
  • Night Sweats
  • Pharyngitis (sore throat)
  • Myalgia (muscle aches and pains)
  • Arthralgia (joint pain)
  • Fatigue
  • Lymphadenopathy (swollen lymph nodes, mainly on the neck)
  • Mouth ulcers

Some people also will experience nausea, diarrhea, or vomiting, and one in five will develop an "HIV rash," a maculopapular skin condition characterized by raised, pink-to-red areas covered with small, pimple-like bumps that often merge together into one. 


After the latent period, signs that the virus is beginning to overcome the immune system include:

  • Swollen lymph glands
  • Candidiasis (thrush), a fungal infection that usually affects the mouth
  • Skin problems, including red, pink, brown, or purplish blotches; white spots or unusual mouth or tongue lesions; or sores on the anus or genitals
  • Night sweats (sleep hyperhidrosis)
  • Extreme weight loss (HIV wasting)

This is also the point at which a person may become ill with opportunistic infections, so-called because they're caused by pathogens that a healthy immune system would usually be able to easily fend off. Shingles and pneumonia are two of the most common.


HIV/AIDS is caused by infection with a virus that attacks and weakens the immune system. It can only be spread in a handful of specific ways, most of which can easily be avoided.

Human Immunodeficiency Virus

The virus that causes HIV/AIDS is classified by scientists as a retrovirus, so called because it transcribes its genetic code in reverse. In most living organisms, a cell's genetic material is encoded from DNA to RNA. A retrovirus is unique in that it uses its RNA coding to produce DNA within an infected cell.

When this occurs, the newly produced DNA is inserted into the host cell's nucleus, effectively hijacking its genetic machinery in order to create multiple copies of itself, each capable of infecting and killing a multitude of other host cells, in this case, white blood cells called "helper" T-cells—in particular, CD4 T-cells that trigger the body's immune response.

By systematically depleting these cells, HIV diminishes the body's ability to identify and neutralize the invading virus, as well as a host of other agents (e.g., viral, bacterial, parasitic) it could otherwise defend itself against.

How HIV Spreads

HIV spreads primarily through sexual contact, the sharing of needles among injectable drug users, accidental blood exposure, and transmission from mother to child during pregnancy. HIV cannot be transmitted through sweat, tears, saliva, feces, or urine.

During the initial (acute) infection, HIV replicates vigorously, infecting and destroying a substantial number of CD4 T-cells before becoming latent—typically for anywhere from eight to 12 years. During this time, the virus will continue to replicate silently, often with little or no signs of illness.

Why Testing Is So Important

It is often only when an opportunistic infection first appears that a person may suspect that he or she is infected with HIV. By this time, the immune system is usually impaired, sometimes severely so. The best way to prevent this from happening is to have an HIV test at least once; people who are at high risk of HIV should be tested as often as once a year.

In addition to HIV, a subset of virus called provirus embeds in cells and tissues called latent reservoirs, where they can't easily be detected by the immune system. Even if HIV is brought under control with antiretroviral drugs, these proviruses can persist, ready to re-emerge as fully formed HIV the moment that treatment fails or the immune system collapses.


There are five ways to test for the presence of the human immunodeficiency virus:

  • Standard point-of-care test, in which a sample of blood is taken in a doctor's office or clinic and examined for the presence of antibodies to HIV. It takes five to 10 days to get results.
  • Rapid point-of-care test, which can yield a result in 20 minutes by measuring both antigens (proteins on the surface of the virus) and antibodies in a sample of blood taken from a finger prick, a sample of saliva swabbed from the gums, or a urine sample.
  • Nucleic acid test: A blood test that measures HIV RNA in blood and is reserved for people who are at high risk of exposure
  • At-home tests that use a sample of saliva and deliver results in about 20 minutes.
  • Home collection kits. These detect antibodies in a sample of blood that you collect yourself and mail to a lab for testing.

Clinics in the United States report a 98.5 percent accuracy rate when using an antibody test and a 99.9 percent accuracy rate when it is combined with a confirmatory test. This translates to one false-positive result for every 250,000 tests. Newer generation tests promise even better results.

Diagnosing AIDS

For someone whose HIV infection has not been controlled, AIDS is diagnosed in one of two ways: By the diagnosis of an AIDS-defining illness or by a CD4 count of under 200 cells per microliter (µL). (Normal CD4 counts range on average from between 800 to 1600 cells per µL.) An HIV-positive person will be monitored regularly in order to keep track of any changes in his or her CD4 count.


Managing the symptoms of HIV infection in the acute stage is usually a matter of getting plenty of rest and quality sleep, drinking lots of fluids, eating well, and taking over-the-counter (OTC) analgesics if necessary to relieve head or body aches.

As soon as a person tests positive for HIV, however, it's vital that he or she begin antiretroviral drugs to get the virus under control and prevent it from replicating and causing serious and irreversible damage to the immune system.

No cure exists for AIDS, but strict adherence to anti-retroviral therapy (ART) can dramatically slow the disease's progress, prevent secondary infections and complications, and prolong life.

As a rule, antiretroviral therapy relies on three different drug molecules, a strategy known as HAART (highly active antiretroviral therapy) developed in 1996. However, this standard triple-drug therapy may be replaced with two-drug therapies such as Juluca (dolutegravir + rilpivirine).

Antiretroviral drugs are organized into five classes based on the stage of the HIV life cycle they affect. There are 28 individual drug molecules and 13 fixed dosed combination (FDC) drugs made up of two or more molecules each. Eight of the FDCs can be used as a single-pill, once-daily therapy.


Although HIV is a highly contagious virus, there is a silver lining: The ways it can be transmitted are well understood and also highly avoidable if specific precautions are taken.

To reduce the risk of becoming infected with the virus, the CDC advises taking certain precautions. Note that some of these strategies apply to people with certain lifestyles:

  • Abstain from sexual contact of any kind that involves exposure to or the exchange of bodily fluids (including semen, vaginal excretions, and menstrual blood)
  • Limit the number of sexual partners you have and make sure anyone you're intimate with has been tested and is HIV-negative
  • Always use a barrier such as a condom during sexual encounters, including oral sex
  • Use new, sterile needles if you are an intravenous drug user: Never shoot up with used needles, syringes, or other "works"
  • Take a daily medication to help protect yourself from infection—known as pre-exposure prophylaxis (PrEP)


HIV infection is a chronic disease, which means it is something that must be dealt with on a daily basis. The most obvious aspects of coping with being HIV positive include doing all that's necessary to stay healthy: Living a healthy lifestyle that will support the health of the immune system; being compliant with medication; and following doctor's orders regarding regular check-ups to keep track of any changes in viral load and overall health.

However, the stigma that persists regarding HIV and continued misunderstandings about how it's transmitted means that coping extends to how you conduct yourself around others and also how you might feel about yourself. For this reason, being upfront with friends and trusted family members about your HIV status can go a long way toward helping you to feel supported and cared for.

Equally important, finding a community of others who also are HIV-positive can be an important lifeline and source of information and advice for dealing with all aspects of being HIV positive. You can get such support by attending local support groups for people who are HIV positive and/or by joining online support groups. If you're having trouble finding a support group, there are multiple resources you can turn to.

A Word From Verywell

There's nothing trivial about being HIV-positive: It's a devastating diagnosis, one that will change your life forever, affect your relationships and lifestyle, and require a high degree of vigilance to stay healthy. But the fact that you can stay healthy while living with HIV is an important fact worth fixating on. Not that long ago, HIV infection was a death sentence: Now it's a chronic situation that can be managed relatively easily and shouldn't affect your lifespan at all. By all means, mourn your previous otherwise healthy life—that's normal and expected. But once you've digested your diagnosis, try to remember that you live in an era when you aren't doomed to become deathly ill with AIDS and then try to live your best life, day by day.

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