The symptomatology of HIV is diverse and varies with the stage of infection. Many of the symptoms related to early infection are due to body's immediate response to the virus itself, wherein the immune system is activated in the presence of a foreign agent. The symptoms are, therefore, a result of the inflammation that occurs when the body actively fights an infection.
The symptoms of later-stage infection are different. These occur when HIV gradually deteriorates the body's immune response, reducing its ability to fight outside infection. The lower the immune response, the greater the risk (and range) of potential infections. The symptoms are, therefore, "HIV-related"—meaning that, while HIV provides the opportunity for infections to develop, the symptoms are the result of a specific "opportunistic" infection.
When a person is infected with HIV, the virus goes through an incubation period of between one to three weeks. During this time, there are generally high levels of virus since the body has yet to mount an adequate defense (in the way of antibodies) to curb the immediate infection.
Because the HIV ELISA test relies on the presence of antibodies to confirm infection, this stage is also known as the "window period." If a test is performed at this stage, the lack of antibodies could effect a false negative result.
The incubation period is immediately followed by "acute seroconversion," wherein the body's immune defenses are fully activated and in combat with the infecting virus. The symptoms that accompany seroconversion can be mild and easily mistaken for the flu or mono. For some, there are no symptoms. For others, however, the effects can be far more pronounced and long-lasting.
At least half of those infected will experience the following symptoms during acute seroconversion:
- Night sweats
- Malaise (a vague feeling of body discomfort or uneasiness)
- Myalgia (a generalized, muscular ache or pain)
- Rash (eczema-like in appearance and usually distributed around the upper parts of the body and/or palms of the hands)
Other symptoms can include sore throat, mouth/esophageal sores, arthralgia (joint pain), and lymphadenopathy (swelling of the lymph glands). Most of these symptoms will resolve within a week to a month on average, while lymphadenopathy can persist in some for years. (While distressing, it's important to note that this is more usually the sign of a robust immune response, rather than an immune failure.
AIDS (Acquired Immune Deficiency Syndrome)
AIDS (or acquired immune deficiency syndrome) is the stage in infection where the body's immune system is compromised, allowing for the development of infections that the body could otherwise prevent. Initially implemented as a means for disease surveillance, the AIDS classification is today defined by the Centers for Disease Control and Prevention (CDC) as an HIV-infected person with
- a CD4 count of under 200 cells per microliter (µL), and/or;
- "certain HIV-related conditions and symptoms."
These "certain" conditions are comprised of specific pulmonary, neurological and gastrointestinal diseases, as well as cancers and other illnesses that can affect those with compromised immune systems. There are currently just over 25 AIDS-defining opportunistic conditions that can occur at various stages in infection, often well above the CD4 threshold of 200 cells/µL.
Without antiretroviral treatment, people with an AIDS diagnosis generally survive for around three years on average.
Opportunistic Infections by CD4 Count
As a guideline, people with CD4 counts of over 500 are less prone to infection. Normal CD4s range anywhere from between 500 to 1600 cells/µL. Once the number falls below 500, the likelihood of infection increases as immune barriers are gradually depleted.
CD4 count between 500 to 250 cells/µL:
- Candidiasis (including oral thrush and vaginal yeast infections)
- Kaposi's sarcoma (pink or purplish skin lesions caused by the HHV-8 virus)
- Oral hairy leukoplakia (white, "hairy" oral lesions caused by the Epstein-Barr virus)
- Herpes zoster (shingles)
- Herpes simplex (genital herpes)
- Bacterial pneumonia (as opposed to viral pneumonia)
- Tuberculosis (or TB; an airborne bacterial infection usually confined to the lungs)
CD4 count between 250 to 100 cells/µL:
- Pneumocystis jirovecii pneumonia (or PCP; a fungal infection of the lungs)
- Invasive cervical cancer
- Coccidioidomycosis (an air- and soil-borne fungal infection; also known as "Valley Fever")
- Extrapulmonary tuberculosis (tuberculosis that presents outside of the lungs)
- Salmonella septicemia (a whole body inflammation caused by salmonella in the blood)
- Esophageal candidiasis (thrush of the esophagus)
CD4 count between 100 to 50 cells/µL:
- Non-Hodgkin lymphoma (or NHL; a group of cancers that occur in the white blood cells)
- Toxoplasmosis (a protozoan parasite that can affect various parts of the body)
- HIV encephalopathy (also known as AIDS dementia complex)
- Progressive multifocal leukoencephalopathy (or PML; a viral infection of the brain)
- Cryptococcosis (a fungal infection that can affect different parts of the body)
- Cystoisoporiasis (a parasitic infection of the intestines)
CD4 count under 50 cells/µL:
- Cytomegalovirus (or CMV; a herpes-type virus that can affect the colon or the eyes)
- Mycobacterium avium complex (or MAC; a bacterial infection often in the lungs or intestines)
- Histoplasmosis (a fungal infection commonly in the lungs)
- Primary CNS lymphoma (cancer affecting the central nervous system)
- HIV wasting syndrome (an unexplainable, profound weight loss accompanied by weakness and persistent diarrhea)
The Bottom Line
Neither symptoms—nor a lack of symptoms—are an indication as to whether an HIV infection has occurred. If you suspect you may have been infected, go to your nearest hospital, clinic or walk-in center for an HIV test.By testing early and implementing optimal antiretroviral therapy, people with HIV can reduce the symptoms of HIV at all stages and maintain normal to near-normal CD4 levels, greatly reducing the risk of opportunistic infections.
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