Hiv

The geographic origin of AIDS is now known

A study published in Science magazine reveals for the first time where, when and how the world's AIDS pandemic originated. Thanks to a statistical analysis of all the genetic data available on the human ...

Nov 13, 2014
popularity 3.5 / 5 (93) | comments 22

Scientists discover pain receptor on T-cells

Researchers at University of California, San Diego School of Medicine have discovered that T-cells – a type of white blood cell that learns to recognize and attack microbial pathogens – are activated by a pain receptor.

Oct 05, 2014
popularity 5 / 5 (13) | comments 1

From HIV to cancer, IL-37 regulates immune system

A University of Colorado Cancer Center study published in this month's Proceedings of the National Academy of Sciences describes the activity of a recently discovered communication molecule of the body's immune system, Interl ...

Nov 03, 2014
popularity 4.7 / 5 (12) | comments 1

Withdrawal from the evolutionary race

In some HIV sufferers, the immune system does not fight off the immune deficiency virus. Instead, the body tolerates the pathogen. A research team headed by ETH Zurich has now determined how strongly patients ...

Sep 18, 2014
popularity 3.2 / 5 (17) | comments 0

HIV/AIDS drugs could be repurposed to treat AMD

A landmark study published today in the journal Science by an international group of scientists, led by the laboratory of Dr. Jayakrishna Ambati, professor & vice chair of the Department of Ophthalmology & Visu ...

Nov 20, 2014
popularity 5 / 5 (7) | comments 0

Human immunodeficiency virus (HIV) is a lentivirus (a member of the retrovirus family) that causes acquired immunodeficiency syndrome (AIDS), a condition in humans in which progressive failure of the immune system allows life-threatening opportunistic infections and cancers to thrive. Infection with HIV occurs by the transfer of blood, semen, vaginal fluid, pre-ejaculate, or breast milk. Within these bodily fluids, HIV is present as both free virus particles and virus within infected immune cells. The four major routes of transmission are unsafe sex, contaminated needles, breast milk, and transmission from an infected mother to her baby at birth (perinatal transmission). Screening of blood products for HIV has largely eliminated transmission through blood transfusions or infected blood products in the developed world.

HIV infection in humans is considered pandemic by the World Health Organization (WHO). Nevertheless, complacency about HIV may play a key role in HIV risk. From its discovery in 1981 to 2006, AIDS killed more than 25 million people. HIV infects about 0.6% of the world's population. In 2009, AIDS claimed an estimated 1.8 million lives, down from a global peak of 2.1 million in 2004. Approximately 260,000 children died of AIDS in 2009. A disproportionate number of AIDS deaths occur in Sub-Saharan Africa, retarding economic growth and exacerbating the burden of poverty. An estimated 22.5 million people (68% of the global total) live with HIV in sub-Saharan Africa, which is also home to 90% of the world's 16.6 million children orphaned by HIV. Treatment with antiretroviral drugs reduces both the mortality and the morbidity of HIV infection. Although antiretroviral medication is still not universally available, expansion of antiretroviral therapy programs since 2004 has helped to turn the tide of AIDS deaths and new infections in many parts of the world. Intensified awareness and preventive measures, as well as the natural course of the epidemic, have also played a role. Nevertheless, an estimated 2.6 million people were newly infected in 2009.

HIV infects vital cells in the human immune system such as helper T cells (specifically CD4+ T cells), macrophages, and dendritic cells. HIV infection leads to low levels of CD4+ T cells through three main mechanisms: First, direct viral killing of infected cells; second, increased rates of apoptosis in infected cells; and third, killing of infected CD4+ T cells by CD8 cytotoxic lymphocytes that recognize infected cells. When CD4+ T cell numbers decline below a critical level, cell-mediated immunity is lost, and the body becomes progressively more susceptible to opportunistic infections.

Most untreated people infected with HIV-1 eventually develop AIDS. These individuals mostly die from opportunistic infections or malignancies associated with the progressive failure of the immune system. HIV progresses to AIDS at a variable rate affected by viral, host, and environmental factors; most will progress to AIDS within 10 years of HIV infection: some will have progressed much sooner, and some will take much longer. Treatment with anti-retrovirals increases the life expectancy of people infected with HIV. Even after HIV has progressed to diagnosable AIDS, the average survival time with antiretroviral therapy was estimated to be more than 5 years as of 2005[update]. Without antiretroviral therapy, someone who has AIDS typically dies within a year.

This text uses material from Wikipedia licensed under CC BY-SA

Latest Spotlight News

Bone loss drugs may help prevent endometrial cancer

A new analysis suggests that women who use bisphosphonates—medications commonly used to treat osteoporosis and other bone conditions—have about half the risk of developing endometrial cancer as women who do not use the ...

People trust typical-looking faces most

Being "average" is often considered a bad thing, but new research suggests that averageness wins when people assess the trustworthiness of a face. The research indicates that, while typical-looking faces ...