HIV and AIDS: From Flu-Like Symptoms to Life-Threatening Infections

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Q: What are the symptoms of HIV/AIDS?

A: Symptoms depend on immune status and evolve as HIV progresses into AIDS.

How HIV weakens our defenses

The human immunodeficiency virus (HIV) weakens the body's immune defenses by destroying CD4 (T-cell) lymphocytes. These white blood cells normally help guard the body against attacks by bacteria, viruses and other germs. When HIV destroys CD4 cells, the body becomes vulnerable to many types of infections. These infections are called “opportunistic” because usually their only opportunity to take hold in the body is when the immune defenses are weak.

HIV infection also increases the risk of certain cancers, illnesses of the brain and nerves, body wasting, and death.

The range of symptoms and illnesses that occur when HIV infection renders the body's immune system defenseless is called acquired immunodeficiency syndrome or AIDS.

Early symptoms

In its early stages, HIV infection may have no symptoms or may cause a flu-like illness that may include: fever, sore throat, rash, nausea and vomiting, diarrhea, fatigue, swollen lymph nodes, muscle aches, headaches, and joint pain. Although most people experience symptoms within the first few weeks of being infected with HIV, many individuals and doctors dismiss the illness as a routine cold or flu. In a small number of cases, this early stage of infection may progress to meningitis (inflammation of membranes covering the brain) or severe flu-like symptoms that require hospitalization.

What happens next?

As the number of CD4 cells drops below the normal level of 500 to 2,000 cells per cubic millimeter of blood, the person may begin to develop swollen lymph glands and skin problems, such as varicella-zoster (shingles), seborrheic dermatitis (dandruff), new or worsening psoriasis, and minor infections. Ulcers can develop around the mouth and herpes outbreaks (oral or genital) may become more frequent.

As CD4 cells continue to die, skin problems and mouth ulcers develop more often. Many people develop diarrhea, fever, unexplained weight loss, joint and muscle pain, and fatigue. Old tuberculosis infections (latent TB) may become active. (Tuberculosis is one of the most common HIV/AIDS-related infections in the developing world.)

Signs of AIDS

Finally, with further decreases in the levels of CD4 cells, the person develops AIDS. According to the Centers for Disease Control and Prevention, some signs that AIDS has developed (known as AIDS-defining conditions) are:

The CD4 cell count has decreased to fewer than 200 cells per cubic milliliter of blood.
An opportunistic infection has developed, indicating that the immune system is severely weakened. These types of infections include specific causes of pneumonia, diarrhea, eye infections and meningitis. Some of the causes of these opportunistic infections include Cryptococcus, reactivation of cytomegalovirus, reactivation of toxoplasma in the brain, wide-spread infection with Mycobacterium avium complex and Pneumocystis jiroveci (formerly called Pneumocystis carinii) in the lungs.
A type of cancer has developed that shows that the immune system is severely weakened. These cancers can include advanced cervical cancer, Kaposi’s sarcoma (a cancer causing round, reddish spots on the skin and in the mouth), certain types of non-Hodgkin’s lymphoma and brain lymphoma.
An AIDS-related brain illness has developed, including HIV encephalopathy (AIDS dementia) or progressive multifocal leukoencephalopathy (PML) that is caused by a specific virus.
There is severe body wasting (HIV wasting syndrome). This means rapid and severe weight loss along with a month or more of weakness, usually accompanied by diarrhea and fever.
There is an AIDS-related lung illness, such as pulmonary lymphoid hyperplasia or lymphoid interstitial pneumonia (usually seen only in children).

The prospect of full blown AIDS is understandably frightening. Because early testing and treatment can greatly delay or virtually eliminate the risk of developing AIDS-defining conditions, if you think you may have been exposed to HIV contact your doctor right away for testing and, if necessary, a treatment plan.

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