Hiv

Earned income tax credit program is a boon for health

A new study by researchers at Columbia University's Mailman School of Public Health reports that the Earned Income Tax Credit program is not only good for people's pocketbooks, but also for their health. Findings showed that ...

Sep 07, 2016
popularity3 comments 0

Experts urge rethink on health target

The concept of premature mortality needs to be either abandoned or redefined if it is not to discriminate against older people, according to a University of East Anglia (UEA) academic and other experts on ageing.

Aug 30, 2016
popularity1 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

The 'love hormone' may quiet tinnitus

(HealthDay)—People suffering from chronic ringing in the ears—called tinnitus—may find some relief by spraying the hormone oxytocin in their nose, a small initial study by Brazilian researchers suggests.

Science can shape healthy city planning

Previous studies have shown a correlation between the design of cities and growing epidemics of injuries and non-communicable diseases such as heart disease, diabetes and cancer. A three-part series published in The Lancet ...

Unique molecular atlas of pancreas produced

Researchers at Karolinska Institutet have managed to produce the first molecular map of the genes that are active in the various cells of the human pancreas. They have also revealed differences in genetic activity between ...

Controlling cell-fate decisions

Rafal Ciosk and his group at the FMI have identified an important link between the Notch signaling pathway and PRC2-mediated gene silencing. They showed that a fine balance between epigenetic silencing and signaling is crucial ...