CDC examines prevalence of undiagnosed HIV

(HealthDay)—Many people have undiagnosed HIV, with the prevalence varying by geographic area, according to a report published in the June 26 issue of the U.S. Centers for Disease Control and Prevention's Morbidity and Mortality ...

Jun 30, 2015
popularity8 comments 0

Potential new HIV therapy seen in immune cells

A research team led by Weill Cornell Medical College scientists has discovered a way to limit replication of the most common form of HIV at a key moment when the infection is just starting to develop. The study, published ...

Jun 29, 2015
popularity62 comments 0

More secondary schooling reduces HIV risk

Longer secondary schooling substantially reduces the risk of HIV infection—especially for girls—and could be a very cost-effective way to halt the spread of the virus, according to researchers from Harvard T.H. Chan School ...

Jun 29, 2015
popularity57 comments 0

New model to study HIV latency in brain cells

Over 35 million people worldwide are currently infected by HIV. Antiviral therapies can keep the virus from multiplying. However, no drug can cure infection so far, because various cell types continue to carry the virus in ...

Jun 18, 2015
popularity12 comments 0

Vitamin D status related to immune response to HIV-1

Vitamin D plays an important part in the human immune response and deficiency can leave individuals less able to fight infections like HIV-1. Now an international team of researchers has found that high-dose vitamin D supplementation ...

Jun 15, 2015
popularity447 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

Repeating aloud to another person boosts recall

Repeating aloud boosts verbal memory, especially when you do it while addressing another person, says Professor Victor Boucher of the University of Montreal's Department of Linguistics and Translation. His findings are the ...

How the brain's wiring leads to cognitive control

How does the brain determine which direction to let its thoughts fly? Looking for the mechanisms behind cognitive control of thought, researchers at the University of Pennsylvania, University of California and United States ...

Runner's high linked to cannabinoid receptors in mice

(Medical Xpress)—A team of researchers from several institutions in Germany has found a link between cannabinoid receptors in mice and what is commonly known as "runner's high." In their paper published in Proceedings of ...

What role does the hippocampus play in memory?

(Medical Xpress)—Meet the hippocampus: A seahorse-shaped structure in the cerebral cortex's medial temporal lobe, it's part of the limbic system, generally believed to be involved in spatial navigation and establishing ...

Snapshot turns T cell immunology on its head

Challenging a universally accepted, longstanding consensus in the field of immunity requires hard evidence. New research from the Australian Research Council Centre of excellence in advanced Molecular imaging has shown the ...