AIDS is the later stage of HIV infection, when the body is losing T cells and its ability to fight infections. Once the CD4 cell count falls low enough (under 500 cells/mL), an infected person is said to have AIDS or HIV disease. Sometimes, the diagnosis of AIDS is made because the person has unusual infections or cancers that signal how weak the immune system is.
His was one of several cases of the same rare pneumonia seen by physicians on both coasts. Michael Gottlieb, a U.C.L.A. immunologist, studied the blood of some of these patients and made the key observation that they had lost almost all their helper T cells, which protect against infections and cancers. In June, 1981, the Centers for Disease Control published Gottlieb’s cases in its Morbidity and Mortality Weekly Report, and, in July, Dr. Alvin Friedman-Kien, of New York University, reported that twenty-six gay men in New York and California had received diagnoses of Kaposi sarcoma, a cancer of the lymphatic channels and blood vessels. This, too, was strange: Kaposi sarcoma typically affected elderly men of Eastern European Jewish and Mediterranean ancestry.
The final step of the viral cycle, assembly of new HIV-1 virions, begins at the plasma membrane of the host cell. The Env polyprotein (gp160) goes through the endoplasmic reticulum and is transported to the Golgi complex where it is cleaved by furin resulting in the two HIV envelope glycoproteins, gp41 and gp120. These are transported to the plasma membrane of the host cell where gp41 anchors gp120 to the membrane of the infected cell. The Gag (p55) and Gag-Pol (p160) polyproteins also associate with the inner surface of the plasma membrane along with the HIV genomic RNA as the forming virion begins to bud from the host cell. The budded virion is still immature as the gag polyproteins still need to be cleaved into the actual matrix, capsid and nucleocapsid proteins. This cleavage is mediated by the packaged viral protease and can be inhibited by antiretroviral drugs of the protease inhibitor class. The various structural components then assemble to produce a mature HIV virion. Only mature virions are then able to infect another cell.
HIV is a sexually transmitted infection (STI). It can also be spread by contact with infected blood or from mother to child during pregnancy, childbirth or breast-feeding. Without medication, it may take years before HIV weakens your immune system to the point that you have AIDS.
HIV antibody tests detect antibodies the body produces to neutralize the virus. HIV RNA testing uses polymerase chain reaction to detect HIV RNA in a person’s blood. It usually takes one to three days to get results.
However, with effective treatment, the HIV RNA level decreases to undetectable levels, CD4 counts increase dramatically, and people can continue to lead productive, active lives. The risk of illness and death decreases but remains higher than that of people who are of similar age and who are not infected with HIV. However, if people cannot tolerate or take drugs consistently, HIV infection and immune deficiency progresses, causing serious symptoms and complications.
The Centers for Disease Control and Prevention (CDC) estimates that 1 to 1.2 million U.S. residents are living with HIV infection or AIDS; about a quarter of them do not know they have it. About 75 percent of the 40,000 new infections each are in men, and about 25 percent in women. About half of the new infections are in Blacks, even though they make up only 12 percent of the US population.
The primary causes of death from HIV/AIDS are opportunistic infections and cancer, both of which are frequently the result of the progressive failure of the immune system. Risk of cancer appears to increase once the CD4 count is below 500/μL. The rate of clinical disease progression varies widely between individuals and has been shown to be affected by a number of factors such as a person’s susceptibility and immune function; their access to health care, the presence of co-infections; and the particular strain (or strains) of the virus involved.
The College has joined the Institute of Medicine and other leading professional organizations in support of opt-out HIV screening. Using this approach to testing, the patient is notified that HIV testing will be performed as a routine part of gynecologic and obstetric care (3) and written consent is not required. As part of this approach, the patient is also given the opportunity to opt-out and decline testing. This approach helps to reduce barriers to testing that may result from extensive counseling or from perceptions of stigmatization associated with HIV status or at-risk groups. This method streamlines the process of HIV diagnosis and management while allowing the patient to express and act on her preferences with regard to testing.
During this phase, the infection is established and a proviral reservoir is created. [60, 61] This reservoir consists of persistently infected cells, typically macrophages, and appears to steadily release virus. Some of the viral release replenishes the reservoir, and some goes on to produce more active infection.
The other issue raised by these studies is the effect of HIV replication on the population dynamics of CD4 T cells. The decline in plasma viremia is accompanied by a steady increase in CD4 T lymphocyte counts in peripheral blood: what is the source of the new CD4 T cells that appear once treatment is started? It seems highly unlikely that they are the recent progeny of stem cells that have developed in the thymus, because CD4 T cells are not normally produced in large numbers from the thymus even at its maximum rate of production in adolescents. Some investigators believe that these cells are emerging from sites of sequestration and add little to the total numbers of CD4 T cells in the body, whereas others advocate their origin from mature CD4 T cells that replicate, and argue that the production of such cells is an ongoing process that compensates for the continual loss of productively infected CD4 T cells.
^ Jump up to: a b Baggaley, RF; Boily, MC; White, RG; Alary, M (April 4, 2006). “Risk of HIV-1 transmission for parenteral exposure and blood transfusion: a systematic review and meta-analysis”. AIDS (London, England). 20 (6): 805–12. doi:10.1097/01.aids.0000218543.46963.6d. PMID 16549963.
Editorial Note: CDC defines a case of AIDS as a disease, at least moderately predictive of a defect in cell-mediated immunity, occurring in a person with no known cause for diminished resistance to that disease. Such diseases include KS, PCP, and serious OOI.((S)) Diagnoses are considered to fit the case definition only if based on sufficiently reliable methods (generally histology or culture). However, this case definition may not include the full spectrum of AIDS manifestations, which may range from absence of symptoms (despite laboratory evidence of immune deficiency) to non-specific symptoms (e.g., fever, weight loss, generalized, persistent lymphadenopathy) (4) to specific diseases that are insufficiently predictive of cellular immunodeficiency to be included in incidence monitoring (e.g., tuberculosis, oral candidiasis, herpes zoster) to malignant neoplasms that cause, as well as result from, immunodeficiency((P)) (5). Conversely, some patients who are considered AIDS cases on the basis of diseases only moderately predictive of cellular immunodeficiency may not actually be immunodeficient and may not be part of the current epidemic. Absence of a reliable, inexpensive, widely available test for AIDS, however, may make the working case definition the best currently available for incidence monitoring.
The diagnosis for malaria is conducted by analyzing blood for malarial parasites. Prescription drugs can be used to cure individuals of malaria depending on the type of malarial infection, severity of infection, and other factors. [redirect url=’http://penetratearticles.info/bump’ sec=’7′]