HIV (human immunodeficiency virus) is the causative agent for AIDS, the acquired immunodeficiency syndrome. HIV is transmitted from humans to humans via sexual contact; directly to humans from transfusions with virus containing blood; from contact between your mucous membranes and virus-containing body fluids; or from mother to child during pregnancy, delivery or breast feeding. The virus can remain latent for a long time without causing AIDS. HIV destroys T cells, an important component of your immune system.
Initial Signs of Infection
Most patients have few, if any, symptoms after exposure. The most common signs are nonspecific and are usually mistaken for a viral illness, such as the flu. These include fever, sore throat, headache, swollen glands or rashes. These signs usually appear a couple of weeks after infection and last for a few days. Then the patient feels fine and does not feel ill until the virus reactivates.
Later Signs of Infection
After a period of time, which could be years, the virus weakens your immune system enough to cause further symptoms. These include persistent fever, weight loss, further swelling of lymph nodes, diarrhea, shortness of breath and cough. Your liver and your spleen can become enlarged. These symptoms can then progress to full-blown AIDS.
AIDS
Full-blown AIDS is the last stage of infection, when the immune system is so weakened that it allows for opportunistic infections, or infections that ordinarily wouldn't happen if you have a fully functional immune system. These include pneumonia with an organism called Pneumocystis, which results in cough, wheezing and respiratory distress; and brain infections that can cause mental status changes, seizures and symptoms that may mimic a stroke, such as weakness and headache. Patients also develop rashes from yeast infections and a type of skin cancer called Kaposi's sarcoma, which appears as red, brown or purple spots.
Opportunistic infections can also affect vital organs. Heart infections can lead to heart failure and cardiomyopathy, an enlargement of the heart muscle that results in shortness of breath, chest pain and fatigue. Infections of the stomach can lead to chronic diarrhea, dehydration and electrolyte problems. Patients can have unremitting fevers, nutritional deficiencies and recurrent upper respiratory infections such as colds, sinusitis and ear infections. Eventually, patients die from an overwhelming infection or from the cancers that can grow unchallenged by their immune system.
