Friday, February 26, 2010

Aids vaccine

Nearly 7,400 people a day are infected with HIV. An AIDS vaccine with 50% efficacy given to 30% of the population would avert 5.6 million new infections in low and middle income countries between 2015 and 2030.

Most initial approaches have focused on the HIV envelope protein. At least thirteen different gp120 and gp160 envelope candidates have been evaluated, in the US predominantly through the AIDS Vaccine Evaluation Group. Most research focused on gp120 rather than gp41/gp160, as the latter are generally more difficult to produce and did not initially offer any clear advantage over gp120 forms.

An AIDS vaccine that appears to have worked at least partly in Thailand may only temporarily protect patients, with the effects starting to wane after a year or so, researchers reported on Thursday.

Aids facts

Human immunodeficiency virus, or HIV, is the virus that causes acquired immune deficiency syndrome (AIDS). The virus weakens a person's ability to fight infections and cancer. People with HIV are said to have AIDS when they develop certain infections or cancers or when their CD4 count is less than 200. CD4 count is determined by a blood test in a doctor's office.

HIV attacks and destroys a type of white blood cell called a CD4 cell. This cell's main function is to fight disease. When a person's CD4 cell count gets low, they are more susceptible to illnesses. AIDS is the final stage of HIV infection. When the immune system CD4 cells drop to a very low level, a person's ability to fight infection is lost. In addition, there are several conditions that occur in people with HIV infection with this degree of immune system failure -- these are called AIDS-defining illnesses.

According to the CDC, 1,051,875 people in the U.S. have been diagnosed with AIDS since the disease was first diagnosed in 1981. They also estimate that 583,298 have died from the disease in the U.S.

Aids awareness

The red ribbon is an international symbol of AIDS awareness that is worn by people all year round and particularly around World AIDS Day to demonstrate care and concern about HIV and AIDS, and to remind others of the need for their support and commitment.

March 10th: National Women and Girls HIV/AIDS Awareness Day
The U.S. Department of Health and Human Service, Office on Women's Health is the lead for this day.

HAART

HAART is the name given to aggressive treatment regimens used to suppress HIV viral replication and the progression of HIV disease. The usual HAART regimen combines three or more different drugs such as two nucleoside reverse transcriptase inhibitors (NRTIs) and a protease inhibitor (PI), two NRTIs and a non-nucleoside reverse transcriptase inhibitor (NNRTI) or other such combinations. These HAART regimens have proven to reduce the amount of active virus and in some cases can lower the number of active virus until it is undetectable by current blood testing techniques.

HAART stands for highly active antiretroviral therapy. It is the combination of at least three ARV drugs that attack different parts of HIV or stop the virus from entering blood cells. Even among people who respond well to HAART, the treatment does not get rid of HIV. The virus continues to reproduce but at a slower pace.

HAART is the therapy, composed of multiple anti-HIV drugs, that is prescribed to many HIV-positive people, even before they develop symptoms of AIDS (and without considering that many will never develop these symptoms). The therapy usually includes one nucleoside analog (DNA chain terminator), one protease inhibitor and either a second nucleoside analog (“nuke”) or a non-nucleoside reverse transcription inhibitor (NNRTI).

Hiv prevention

The world’s first major HIV prevention campaigns targeted gay and bisexual men in US cities. They began around 1984 and were run by non-governmental organisations such as the San Francisco AIDS Foundation, AIDS Project Los Angeles and Gay Men’s Health Crisis in New York. These community-based groups had for some time been teaching people about AIDS and how it was most likely acquired, but they found that this was not enough. Even men who saw friends suffer and die of AIDS found it difficult to make long-term lifestyle changes.

Across the world, a small but growing number of countries have reduced HIV prevalence through sound prevention efforts. The high rates of transmission of HIV result largely from failure to use the available and effective prevention strategies and tools, and poor coverage of HIV prevention programmes. HIV prevention services were only reaching 20% of people in need in 2005, while coverage for key populations at higher risk of exposure to HIV were considerably lower.

The HIV Prevention Trials Network is a worldwide collaborative clinical trials network that develops and tests the safety and efficacy of primarily non-vaccine interventions designed to prevent the transmission of HIV.