Doctor's Notes on HIV/AIDS
Human immunodeficiency virus, or HIV, is a virus that is transmitted by contact with body fluids of an infected person. The HIV virus weakens the body’s immune system, making it more difficult to fight infections and cancer. AIDA or acquired immune deficiency syndrome is the more advanced stage of infection. HIV infection progresses to AIDS when certain infections or cancers are present or when a person’s CD4 cell (a type of immune cell) count is less than 200.
The initial infection with HIV may or may not cause symptoms. Some people get flu-like symptoms such as fever, cough, fatigue, and muscle aches, within a few weeks after they have been infected. A person can have HIV for many years before developing any symptoms. Signs and symptoms associated with the progression of HIV infection to AIDS can include persistent fever, night sweats, weight loss, severe fatigue, and swollen lymph nodes.
Many people with HIV do not know they are infected. In the United States, it is likely that 14% of HIV-positive individuals are unaware of their infection. HIV infection progresses in three very general stages.
Stage 1: Acute HIV Infection
Many people do not develop symptoms or signs at all after they are infected with HIV. Others will have signs and symptoms in the first two to four weeks after HIV infection, referred to as primary or acute HIV infection.
- open sores or ulcers in the mouth (like canker sores, also known as aphthous ulcers);
- weight loss;
- sweating or night sweats;
- appetite loss;
- rash that may come and go quickly;
- sore throat; and
- swollen lymph nodes (glands) in the neck and groin.
These HIV-associated symptoms usually disappear within a few weeks.
Stage 2: Clinical Latency Stage (HIV Dormancy)
After acute infection, the virus appears to become dormant, and the person feels normal. This stage of HIV infection may last an average of eight to 10 years, but it can vary among individuals and strains of HIV. A recently identified aggressive HIV strain from Cuba has been found to progress to AIDS in as little as three years.
During the latent period, the virus continues to multiply actively. It infects and kills critical infection fighting cells, a type of white blood cell called CD4 cells or T helper cells (T cells). Even though the person has no symptoms, he or she is contagious and can pass HIV to others through the routes described above. At the end of this phase, as the virus overwhelms the CD4 cells, the HIV viral load starts to rise, and the CD4 count begins to drop. As this happens, the person may begin to have symptoms as the virus levels increase in the body. This is stage 3.
Stage 3: Acquired Immunodeficiency Syndrome (AIDS)
AIDS is the later stage of HIV infection, when the body is losing T cells and its ability to fight infections. Once the CD4 count falls low enough (under 500 cells/mL), an infected person is said to have AIDS or HIV disease. Sometimes, the diagnosis of AIDS is made because the person has unusual infections or cancers that signal how weak the immune system is.
The infections that occur with AIDS are called opportunistic infections because they take advantage of the opportunity to infect a weakened host. A person diagnosed with AIDS may need to be on antibiotic prophylaxis to prevent certain opportunistic infections from occurring. The AIDS-defining infections include (but are not limited to) the following:
- Pneumonia caused by Pneumocystis jiroveci, which causes severe shortness of breath and dry cough
- Toxoplasmosis, a brain infection which can cause problems with thinking, headache, or symptoms that mimic a stroke
- Widespread (disseminated) infection with a bacteria called Mycobacterium avium complex (MAC), which can cause fever, diarrhea, and weight loss
- Yeast (Candida) infection of the mouth and swallowing tube (esophagus), which causes pain with swallowing
- Disseminated diseases with certain fungi: Cryptococcus neoformans is a typical example and causes a slowly progressing meningitis.
- Polyoma virus or JC virus can cause progressive multifocal leukoencephalopathy, an incurable brain infection that leads to death.
A weakened immune system can also lead to other unusual conditions:
MYTH. The last stage of HIV (human immunodeficiency virus) infection is AIDS (acquired immune deficiency syndrome). Once you get an HIV infection, you have it for life, but it does not progress to AIDS in all people. With antiretroviral therapy treatment (ART) many people can live a normal life expectancy with HIV infection.
Kasper, D.L., et al., eds. Harrison's Principles of Internal Medicine, 19th Ed. United States: McGraw-Hill Education, 2015.