In June 1981, news of a mysterious disease first began making headlines out of San Francisco, Los Angeles and New York. People who were impacted developed unusual infections and grew sick as their immune systems failed. Those early days of what we now know as the HIV epidemic were marked by great fear and loss. By the time the first medicine was introduced in the United States in 1987, more than 5,000 people had died and the number of people impacted continued to balloon……..Continue reading….
By: Gilead Sciences
Source: 3BL
.
Critics:
Many HIV-positive people are unaware that they are infected with the virus. For example, in 2001 less than 1% of the sexually active urban population in Africa had been tested, and this proportion is even lower in rural populations. Furthermore, in 2001 only 0.5% of pregnant women attending urban health facilities were counselled, tested or received their test results. Again, this proportion is even lower in rural health facilities.
Since donors may therefore be unaware of their infection, donor blood and blood products used in medicine and medical research are routinely screened for HIV. HIV-1 testing is initially done using an enzyme-linked immunosorbent assay (ELISA) to detect antibodies to HIV-1. Specimens with a non-reactive result from the initial ELISA are considered HIV-negative, unless new exposure to an infected partner or partner of unknown HIV status has occurred. Specimens with a reactive ELISA result are retested in duplicate.
If the result of either duplicate test is reactive, the specimen is reported as repeatedly reactive and undergoes confirmatory testing with a more specific supplemental test (e.g., a polymerase chain reaction (PCR), western blot or, less commonly, an immunofluorescence assay (IFA)). Only specimens that are repeatedly reactive by ELISA and positive by IFA or PCR or reactive by western blot are considered HIV-positive and indicative of HIV infection.
Specimens that are repeatedly ELISA-reactive occasionally provide an indeterminate western blot result, which may be either an incomplete antibody response to HIV in an infected person or nonspecific reactions in an uninfected person. Although IFA can be used to confirm infection in these ambiguous cases, this assay is not widely used. In general, a second specimen should be collected more than a month later and retested for persons with indeterminate western blot results.
Although much less commonly available, nucleic acid testing (e.g., viral RNA or proviral DNA amplification method) can also help diagnosis in certain situations. In addition, a few tested specimens might provide inconclusive results because of a low quantity specimen. In these situations, a second specimen is collected and tested for HIV infection. Modern HIV testing is extremely accurate, when the window period is taken into consideration. A single screening test is correct more than 99% of the time.
The chance of a false-positive result in a standard two-step testing protocol is estimated to be about 1 in 250,000 in a low risk population. Testing post-exposure is recommended immediately and then at six weeks, three months, and six months. HIV/AIDS research includes all medical research that attempts to prevent, treat, or cure HIV/AIDS, as well as fundamental research about the nature of HIV as an infectious agent and AIDS as the disease caused by HIV.
Many governments and research institutions participate in HIV/AIDS research. This research includes behavioral health interventions, such as research into sex education, and drug development, such as research into microbicides for sexually transmitted diseases, HIV vaccines, and anti-retroviral drugs. Other medical research areas include the topics of pre-exposure prophylaxis, post-exposure prophylaxis, circumcision, and accelerated aging effects.
The management of HIV/AIDS typically involves the use of multiple antiretroviral drugs. In many parts of the world, HIV has become a chronic condition, with progression to AIDS increasingly rare. HIV latency and the resulting viral reservoir in CD4+ T cells, dendritic cells, and macrophages is the main barrier to eradication of the virus. While HIV is highly virulent, transmission through sexual contact does not occur when an HIV-positive individual maintains a consistently undetectable viral load (<50 copies/ml) due to antiretroviral treatment.
This concept was first proposed by the Swiss Federal Commission for AIDS/HIV in 2008 in what is known as the Swiss Statement. Although initially controversial, subsequent studies have confirmed that the risk of transmitting HIV through sex is effectively zero when the HIV-positive person has a consistently undetectable viral load, a concept now widely known as U=U, or “Undetectable = Untransmittable.
In 1983, two separate research groups led by American Robert Gallo and French investigators Françoise Barré-Sinoussi and Luc Montagnier independently declared that a novel retrovirus may have been infecting AIDS patients, and published their findings in the same issue of the journal Science. Gallo claimed that a virus his group had isolated from a person with AIDS was strikingly similar in shape to other human T-lymphotropic viruses (HTLVs) his group had been the first to isolate.
Gallo admitted in 1987 that the virus he claimed to have discovered in 1984 was in reality a virus sent to him from France the year before.[170] Gallo’s group called their newly isolated virus HTLV-III. Montagnier’s group isolated a virus from a patient presenting with swelling of the lymph nodes of the neck and physical weakness, two classic symptoms of primary HIV infection. Contradicting the report from Gallo’s group, Montagnier and his colleagues showed that core proteins of this virus were immunologically different from those of HTLV-I.
Montagnier’s group named their isolated virus lymphadenopathy-associated virus (LAV). As these two viruses turned out to be the same, in 1986 LAV and HTLV-III were renamed HIV. Another group working contemporaneously with the Montagnier and Gallo groups was that of Jay A. Levy at the University of California, San Francisco. He independently discovered the AIDS virus in 1983 and named it the AIDS associated retrovirus (ARV).
This virus was very different from the virus reported by the Montagnier and Gallo groups. The ARV strains indicated, for the first time, the heterogeneity of HIV isolates and several of these remain classic examples of the AIDS virus found in the United States.
Emerging Concepts in the Immunopathogenesis of AIDS”.
Opportunistic Infections in HIV-Infected Patients Differ Strongly in Frequencies and Spectra between Patients with Low CD4+ Cell Counts Examined Postmortem and Compensated Patients Examined Antemortem Irrespective of the HAART Era”. 2007 AIDS epidemic update”
Contaminants in human milk: weighing the risks against the benefits of breastfeeding”. public domain: “
Preventing Mother-to-Child Transmission of HIV”.
Cell death by pyroptosis drives CD4 T-cell depletion in HIV-1 infection”.
HIV-1 induced bystander apoptosis”.
International Committee on Taxonomy of Viruses
Human Immunodeficiency Virus Type 2″.
HIV Sequence Compendium 2008 Introduction
Core structure of gp41 from the HIV envelope glycoprotein”
Few and far between: how HIV may be evading antibody avidity”.
Crystal structure of key HIV protein reveals new prevention, treatment targets”
.
.
Leave a Reply