- human immunodeficiency virus
- acquired immune deficiency syndrome
Human immunodeficiency virus, or HIV, infection damages the body's immune system. Over time, it leads to acquired immune deficiency syndrome, or AIDS.
What is going on in the body?
HIV affects the immune system in broad and devastating ways. Its main target is a special immune system cell called the CD4+ T lymphocyte. These cells help the body fight infections of all kinds. When HIV infects these cells, it decreases their numbers and affects how the cells that are left function.
After an adult is infected with HIV, he or she usually has no obvious symptoms for 5 to 10 years. During this time, however, the virus is slowly attacking the immune system. When the immune system is weakened enough, it becomes susceptible to other organisms that the body can usually fight off or keep under control. These other organisms include bacteria, other viruses, fungi, and parasites.
Many serious health problems occur as a result of the immune system damage caused by HIV. The most serious is AIDS.
What are the causes and risks of the disease?
HIV infection is caused by a type of virus known as a lentivirus. Seventy percent of HIV infections worldwide are sexually transmitted
, or spread by sexual contact. The remaining 30% of the infections are spread in one of the following ways:
- by contact with HIV-infected blood or other secretions at the site of a cut or wound
- by skin punctures from needles or other sharp devices contaminated with HIV-infected blood or other body secretions
- from contaminated blood products received before March 1985, when a screening test for HIV in blood products was first used
- from mother to infant around the time of birth
- through breastfeeding
Following are some of the risk factors for HIV infections:
- having received blood transfusions
or blood products, especially from 1975 to March 1985
- having received pooled plasma for treatment of hemophilia, a blood clotting disorder
- intravenous drug use
- sexual activity with an infected individual, particularly male homosexual contact
What can be done to prevent the disease?
Although practicing safer sex
cannot completely protect a person from HIV, it can lower the risk. Condoms help prevent passing along the virus. Research in laboratories has shown that a spermicide called nonoxynol-9 kills or stops the growth of HIV. However, there are not
yet any studies that prove spermicides prevent HIV infection in humans. Some experts do believe that using spermicide on a condom or putting it into the vagina can kill some HIV organisms before they can infect the woman. It is safest to avoid sexual intercourse with people who have HIV infection or unknown HIV status and those who use IV drugs.
A person should not share needles, syringes, or other drug paraphernalia that could carry tainted blood or body fluids with anyone. When caring for someone in an emergency, it is important to wear gloves to protect against HIV in body secretions.
A woman who is pregnant or thinking about getting pregnant, should ask her doctor to test her for HIV. If a woman has HIV, steps can be taken during pregnancy and birth to avoid passing it to her baby.
How is the disease diagnosed?
The body produces antibodies to fight off HIV infection. HIV is usually diagnosed by blood tests called antibody titer tests. The enzyme immunoassay,
or EIA, is used as a screening test. If this test is positive, a HIV Western blot
test is done to confirm the diagnosis. The virus can also be detected by testing for viral proteins and by doing blood cultures. Other tests may be ordered to help diagnose complications of HIV infection, such as pneumonia.
Negative tests do not always mean that a person is free of infection. Weeks or months might pass after exposure to the virus before antibodies can be detected in the body.
Long Term Effects
What are the long-term effects of the disease?
HIV causes many long-term effects, including:
- autoimmune disorders, which cause the body to destroy its own tissues
- cancers, such as Kaposi's sarcoma
and non-Hodgkin''s lymphoma
infections, which can affect vision
caused by cryptococcal organisms
- neuropsychiatric disorders, which change the person's thinking and interaction with others
- premature death
- toxoplasmosis, a respiratory infection
What are the risks to others?
Having unprotected sexual intercourse or sharing needles or syringes puts a person and his or her partners at risk for HIV. People with known or suspected HIV infection should not donate the following:
- body organs
What are the treatments for the disease?
There are a number of medicines that effectively treat HIV. Over the past few years, combinations of certain drugs have been very promising in controlling HIV. Some of them are as follows:
- antibiotics, such as trimethoprim-sulfamethoxazole or pentamidine
- antifungal medicines, such as amphotericin B and flucytosine
- antiparastic medicines, such as pyrimethamine
- antiviral medicines, such as zidovudine, lamivudine, nevirapine, and ganciclovir
- glucocorticoids, such as prednisone
- protease inhibitors, such as indinavir
People who have HIV infection face significant health problems and stress
. Following are some helpful interventions:
- Eat a healthy diet, following the food guide pyramid.
- Get plenty of rest and sleep.
- Join support groups.
- Take medicines to deal with emotional symptoms.
- Use psychotherapy.
- Use relaxation therapy
and other stress
What are the side effects of the treatments?
Unfortunately, most HIV medicines have many side effects, depending on the drug being taken. Some more common side effects include:
Some less common side effects are as follows:
- changes in the brain and behavior
- inflammation of the pancreas
- kidney stones
What happens after treatment for the disease?
There is no cure for HIV infection at this time. The goal of treatment is to keep the virus under control with the hope of preventing further immune damage. Currently, a person must be treated for life.
How is the disease monitored?
Someone with HIV infection will have regular visits with the healthcare provider, along with periodic blood tests. Any new or worsening symptoms should be reported to the provider.