Wednesday 19 October 2011

HIV/AIDS

HIV/AIDS Symptoms

Many people do not develop symptoms after getting infected with HIV. Some people have a flu-like illness within several days to weeks after exposure to the virus. They complain of fever, headache, tiredness, and enlarged lymph glands in the neck. These symptoms usually disappear on their own within a few weeks.

  • Following initial infection, you may have no symptoms. The progression of disease varies widely among individuals. This state may last from a few months to more than 10 years.

    • During this period, the virus continues to multiply actively and infects and kills the cells of the immune system. The immune system allows us to fight against the bacteria, viruses, and other infectious causes.
    • The virus destroys the cells that are the primary infection fighters, called CD4+ or T4 cells.
  • Once the immune system weakens, a person infected with HIV can develop the following symptoms:

  • Lack of energy
  • Weight loss
  • Frequent fevers and sweats
  • Persistent or frequent yeast infections
  • Persistent skin rashes or flaky skin
  • Short-term memory loss
  • Mouth, genital, or anal sores from herpes infections.

AIDS is the most advanced stage of HIV infection. The definition of AIDS includes all HIV-infected people who have fewer than 200 CD4+ cells per microliter of blood. The definition also includes 26 conditions that are common in advanced HIV disease but that rarely occur in healthy people. Most of these conditions are infections caused by bacteria, viruses, fungi, parasites, and other organisms. Opportunistic infections are common in people with AIDS. Nearly every organ system is affected. Some of the common symptoms include the following:

  • Cough and shortness of breath
  • Seizures and lack of coordination
  • Difficult or painful swallowing
  • Mental symptoms such as confusion and forgetfulness
  • Severe and persistent diarrhea
  • Fever
  • Vision loss
  • Nausea, abdominal cramps, and vomiting
  • Weight loss and extreme fatigue
  • Severe headaches with neck stiffness
  • Coma
 People with AIDS are prone to develop various cancers such as Kaposi sarcoma, cervical cancer, and cancers of the immune system known as lymphomas. Kaposi sarcoma causes round, brown, reddish or purple spots that develop in the skin or in the mouth. After the diagnosis of AIDS is made, the average survival time has been estimated to be 2-3 years.


Stages of HIV Infection

The U.S. Centers for Disease Control and Prevention (CDC) classify HIV infection into four stages.1

Stages of HIV infection

  • Stage 1: There are no AIDS-related conditions AND the CD4+ cell count is greater than 500 or the percent of CD4+ cells is at least 29% of all lymphocytes.
  • Stage 2: There are no AIDS-related conditions AND the CD4+ cell count is 200 to 499 or the percent of CD4+ cells is 14% to 28% of all lymphocytes.
  • Stage 3: The CD4+ cell count is lower than 200, the percent of CD4+ cells is less than 14% of all lymphocytes, or an AIDS-related condition is present.
  • Stage unknown: No information is available on the CD4+ cell count or the presence of AIDS-related conditions.
In general, the higher the CD4+ count, the less likely it is that opportunistic diseases will occur. Most people who have untreated HIV experience a gradual drop in the number of CD4+ cells. Each person responds uniquely to this decline.

Understanding HIV/AIDS -- the Basics

AIDS (acquired immune deficiency syndrome) isn't a disease in itself. Instead, AIDS is a condition that develops when a person's body has been weakened by HIV (the human immunodeficiency virus). HIV is found in blood and sexual fluids and spreads mainly through unprotected sexual contact and the sharing of IV drug needles and equipment.
When a person becomes infected with HIV, it damages the immune system. A "deficient" immune system is unable to protect a person -- a problem called immunodeficiency. The immune system can no longer fight off the many germs and pathogens that a person normally encounters, so a person infected with HIV becomes ill from diseases that don't usually affect someone without HIV.
It can take HIV many years to damage the immune system enough to make the person vulnerable to these diseases, called opportunistic infections (OIs). These infections take the "opportunity" to invade because the immune system cannot fight them off. When doctors see someone with one of these diseases, they know that HIV is probably responsible, and the person may be diagnosed with AIDS.
As HIV slowly invades a specific immune cell -- the CD4 T-cell -- HIV uses the immune cell's genetic material to reproduce itself and then kills the CD4 T-cell.
An HIV-infected person may not have any symptoms of disease during this time -- called the asymptomatic period. This can last 10 years or more for some people. During this time, the person's CD4 T-cell count is watched closely to guide treatment. The goal is to keep an infected person from advancing to AIDS. Once the CD4 T-cell count goes below 200, a person is diagnosed with AIDS.

The Worldwide HIV/AIDS Pandemic

The first AIDS case was documented in 1981, and HIV has since spread worldwide. In 2009, almost 2 million people died worldwide, and the epidemic continues to spread. Sub-Saharan Africa has the greatest number of people who are infected. The World Health Organization (WHO) and the United Nations' UNA IDS office estimate that over 33% of adults are infected with HIV in some areas of Africa. Millions of children have been orphaned. The epidemic is also growing rapidly in Eastern Europe and Asia. More than 33 million people worldwide are now living with HIV.
In the United States and the developed world, the use of combination treatments has turned AIDS into a chronic disease. People now live long lives with HIV when they work closely with their health care providers and are committed to their treatment plans. Unfortunately, AIDS medications are expensive and unavailable to the majority of people in the world living with AIDS.
There are growing concerns that some high-risk groups believe they don't have to be worried about HIV anymore. The fact that people now live longer with HIV doesn't change the fact that HIV is a life-threatening illness and can infect anyone who exchanges infected blood or sexual fluids with another person.

What Causes HIV/AIDS?

HIV lives in human blood and sexual fluids (semen and vaginal secretions). The infection is spread from person to person when these body fluids are shared, usually during vaginal or anal sexual contact or when sharing IV drugs. HIV does not live in saliva, tears, urine, or perspiration -- so HIV cannot be spread by casual contact with these body fluids. It can be spread through oral sex, though the risk is small.
HIV cannot survive for long outside the human body and dies quickly when the body fluid it's in dries up. It is not spread by animals or insects and is not found on public surfaces. It's actually not as easy to get as other infectious diseases.
A mother can pass HIV to her child during birth when the child is exposed to the mother's infected blood. Breastfeeding does carry a risk for HIV infection, though in some areas of the developing world, breastfeeding is considered safer than feeding a newborn contaminated water.
There are two main types of HIV, called HIV-1 and HIV-2. HIV-2 is rarely found outside Africa and parts of Asia, so there is no need to test for it specifically -- unless a person has had contact with someone from an area of the world where HIV-2 is common.
All of the world's scientists working in the field of AIDS agree that HIV is the cause of the AIDS syndrome. Other theories are not supported by scientific evidence.
Dirty needles used for tattoos and body piercing can spread HIV. Be sure these needles are used only once and then thrown away.
Blood transfusions were once a concern, but all blood products used in the United States today are tested for several infectious diseases, including HIV. If signs of disease or other problems are found in donated blood, the person who donated the blood is notified to be retested by their health care provider and is not permitted to continue donating blood. Any donated blood that tests positive for HIV is disposed of and never makes it into the public blood supply.



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