HIV/AIDS

HIV/AIDS:

This article is concerning the illness. For the virus, see HIV. For alternative uses, see AIDS (disambiguation).
HIV/AIDS
A red ribbon within the form of a bow
The red ribbon may be a image for commonality with HIV-positive individuals and people living with AIDS.
Classification and external resources
Specialty Infectious illness
ICD-10 B20 – B24
ICD-9-CM 042-044
OMIM 609423
DiseasesDB 5938
MedlinePlus 000594
eMedicine emerg/253
Patient UK HIV/AIDS
MeSH D000163
Human immunological disorder viral infection and purchased immune deficiency syndrome (HIV/AIDS) may be a spectrum of conditions caused by infection with the human immunological disorder virus (HIV).s. this is often usually followed by a chronic amount while not symptoms. because the infection progresses, it interferes a lot of and a lot of with the system, creating the person rather more liable to common infections like T.B., moreover as expedient infections and tumors that don't sometimes have an effect on people that have operating immune systems. The late symptoms of the infection ar said as AIDS. This stage is commonly sophisticated by associate infection of the respiratory organ referred to as pneumocytosis, severe weight loss, a sort of cancer referred to as sarcoma, or alternative AIDS-defining conditions.
HIV is transmitted primarily via unprotected sexual issues (including anal and oral sex), contaminated blood transfusions, hypodermic needles, and from mother to kid throughout physiological state, delivery, or breastfeeding. Some bodily fluids, like secretion and tears, don't transmit HIV. Common strategies of HIV/AIDS interference embody encouraging sexual activity, needle-exchange programs, and treating people who ar infected. there's no cure or vaccine; but, antiretroviral treatment will slow the course of the illness and will cause a near-normal life. whereas antiretroviral treatment reduces the chance of death and complications from the illness, these medications ar dearly-won and have aspect effects. while not treatment, the common survival time once infection with HIV is calculable to be nine to eleven years, betting on the HIV subtype.
Since its discovery, AIDS has caused associate calculable thirty six million deaths worldwide (as of 2012). In 2013 it resulted in concerning one.34 million deaths. As of 2012, or so thirty five.3 million individuals live with HIV globally. HIV/AIDS is taken into account a pandemic—a illness eruption that is gift over an oversized space and is actively spreading. Genetic analysis indicates that HIV originated in western Africa throughout the late nineteenth or early twentieth century.AIDS was 1st recognized by the u.  s. Centers for illness management and interference (CDC) in 1981 and its cause—HIV infection—was known within the early a part of the last decade.
HIV/AIDS has had an excellent impact on society, each as associate sickness and as a supply of discrimination. The illness additionally has important economic impacts. There ar several misconceptions concerning HIV/AIDS like the idea that it is transmitted by casual non-sexual contact. The illness has become subject to several controversies involving faith. it's attracted international medical and political attention moreover as large-scale funding since it had been known within the Eighties

.signs and symptms:
Main article: Signs and symptoms of HIV/AIDS
There ar 3 main stages of HIV infection: acute infection, clinical latency and AIDS.

Acute infection:
A diagram of somebody's body part labeled  with the foremost common symptoms of AN acute HIV infection
Main symptoms of acute HIV infection
The initial amount following the contraction of HIV is termed acute HIV, primary HIV or acute retroviral syndrome. several people develop AN influenza-like ill health or a mononucleosis-like ill health 2–4 weeks post exposure whereas others don't have any vital symptoms. Symptoms occur in 40–90% of cases and most ordinarily embody fever, massive tender bodily fluid nodes, throat inflammation, a rash, headache, and/or sores of the mouth and genital organ. The rash, that happens in 20–50% of cases, presents itself on the trunk and is maculopapular, classically. Some individuals conjointly develop expedient infections at this stage.gi symptoms like nausea, ejection or looseness of the bowels could occur, as could neurologic symptoms of peripheral pathology or infectious polyneuritis. The period of the symptoms varies, however is typically one or period.

Due to their nonspecific character, these symptoms don't seem to be usually recognized as signs of HIV infection. Even cases that do get seen by a GP or a hospital ar usually misdiagnosed mutually of the various common infectious diseases with overlapping symptoms. Thus, it's suggested that HIV be thought of in individuals presenting AN unexplained fever United Nations agency could have risk factors for the infection.

Clinical latency:
The initial symptoms ar followed by a stage known as clinical latency, symptomless HIV, or chronic HIV. while not treatment, this second stage of the explanation of HIV infection will last from concerning 3 years to over twenty years (on average, concerning eight years). whereas usually there ar few or no symptoms initially, close to the tip of this stage many folks expertise fever, weight loss, gi issues and muscle pains. Between fifty and seventieth of individuals conjointly develop persistent generalized pathology, characterised by unexplained, non-painful enlargement of quite one cluster of bodily fluid nodes (other than within the groin) for over 3 to 6 months.

Although most HIV-1 infected people have a detectable infectious agent load and within the absence of treatment can eventually reach AIDS, atiny low proportion (about five%) retain high levels of CD4+ T cells (T helper cells) while not antiretroviral medical aid for quite 5 years. These people ar classified as HIV controllers or long nonprogressors (LTNP). Another cluster is {those United Nations agency|those that|people who} conjointly maintain an occasional or undetectable infectious agent load while not anti-retroviral treatment who ar referred to as "elite controllers" or "elite suppressors". They represent around one in three hundred infected persons.

Acquired immunological disorder syndrome:
A diagram of somebody's body part labeled  with the foremost common symptoms of AIDS
Main symptoms of AIDS.
Acquired immunological disorder syndrome (AIDS) is outlined in terms of either a CD4+ T cell count below two hundred cells per µL or the prevalence of specific diseases in association with AN HIV infection. within the absence of specific treatment, around 1/2 individuals infected with HIV develop AIDS at intervals 10 years. the foremost common initial conditions that conscious of the presence of AIDS ar pneumocystis carinii pneumonia (40%), debility within the variety of HIV wasting syndrome (20%) and muscular structure fungal infection. alternative common signs embody revenant tract infections.

Opportunistic infections could also be caused by bacterium, viruses, fungi and parasites that ar ordinarily controlled by the system. that infections occur partially depends on what organisms ar common within the person's setting.These infections could have an effect on nearly each organ system.

People with AIDS have AN increased  risk of developing varied infectious agent elicited cancers together with Kaposi's sarcoma, Burkitt's cancer, primary central system cancer and cervical cancer. Kaposi's sarcoma is that the commonest cancer occurring in ten to twenty of individuals with HIV. The second commonest cancer is cancer that is that the reason for death of nearly Sixteen Personality Factor Questionnaire of individuals with AIDS and is that the initial sign of AIDS in three to 4WD. each these cancers ar related to human herpesvirus eight. Cervical cancer happens a lot of oftentimes in those with AIDS as a result of its association with human papillomavirus (HPV).mucous membrane cancer (of the layer that lines the inner a {part of} eyelids and also the white part of the eye) is a lot of common in those with HIV.

Additionally, individuals with AIDS oftentimes have general symptoms like prolonged fevers, sweats (particularly at night), swollen bodily fluid nodes, chills, weakness, and unwitting weight loss. looseness of the bowels is another common symptom gift in concerning ninetieth of individuals with AIDS. they will even be tormented by numerous medicine and neurologic symptoms freelance of expedient infections and cancers.

Transmission:
Average per act risk of obtaining HIV
by exposure route to AN infected supply
Exposure route Chance of infection
Blood transfusion 90%
Childbirth (to child) 25%
Needle-sharing injection drug use 0.67%
Percutaneous needle stick 0.30%
Receptive anal intercourse* 0.04–3.0%
Insertive anal intercourse* 0.03%
Receptive penile-vaginal intercourse* 0.05–0.30%
Insertive penile-vaginal intercourse* 0.01–0.38%
Receptive oral intercourse*§ 0–0.04%
Insertive oral intercourse*§ 0–0.005%
* forward no prophylactic use
§ supply refers to oral intercourse
performed on a person
HIV is transmitted by 3 main routes: sexual contact, exposure to infected body fluids or tissues, and from mother to kid throughout gestation, delivery, or breastfeeding (known as vertical transmission). there's no risk of getting HIV if exposed to excretory product, nasal secretions, saliva, sputum, sweat, tears, urine, or vomit unless these ar contaminated with blood. it's attainable to be co-infected by quite one strain of HIV—a condition referred to as HIV infection.

Sexual;
The most frequent mode of transmission of HIV is thru sexual contact with AN infected person. the bulk of all transmissions worldwide occur through heterosexual contacts (i.e. sexual contacts between individuals of the other sex); but, the pattern of transmission varies considerably among countries. within the u.  s., as of 2009, most sexual transmission occurred in men United Nations agency had sex with men, with this population accounting for sixty fourth of all new cases.

With relevancy unprotected heterosexual contacts, estimates of the chance of HIV transmission per sexual act seem to be four to 10 times higher in low-income countries than in high-income countries. In low-income countries, the chance of female-to-male transmission is calculable as zero.38% per act, and of male-to-female transmission as zero.30% per act; the equivalent estimates for high-income countries ar zero.04% per act for female-to-male transmission, and 0.08% per act for male-to-female transmission. the chance of transmission from anal sex is very high, calculable as one.4–1.7% per act in each heterosexual and homosexual contact. whereas the chance of transmission from sexual perversion is comparatively low, it's still gift. the chance from receiving sexual perversion has been represented as "nearly nil"; but, a number of cases are reported . The per-act risk is calculable at 0–0.04% for receptive oral intercourse. In settings involving whoredom in low financial gain countries, risk of female-to-male transmission has been calculable as two.4% per act and male-to-female transmission as zero.05% per act.

Risk of transmission will increase within the presence of the many sexually transmitted infection. and venereal ulcers. venereal ulcers seem to extend the chance around multiple. alternative sexually transmitted infections, like gonorrhoea, chlamydia, protozoal infection, and microorganism vaginosis, ar related to somewhat smaller will increase in risk of transmission.

The infectious agent load of AN infected person is a crucial risk think about each sexual and mother-to-child transmission. throughout the primary two.5 months of AN HIV infection a personality's infectiousness is twelve times higher as a result of this high infectious agent load. If the person is within the late stages of infection, rates of transmission ar around multiple bigger.

Commercial sex staff (including those in pornography) have AN increased  rate of HIV. Rough sex will be an element related to AN increased  risk of transmission.statutory offence is additionally believed to hold AN increased  risk of HIV transmission as condoms ar seldom worn, physical trauma to the duct or body part is probably going, and there could also be a bigger risk of synchronic sexually transmitted infections.

Body fluids;
 A black-and-white poster of a young man with a towel in his manus with the words "If you're dabbling with medicine you'll be dabbling along with your life" on top of him
CDC poster from 1989 lightness the threat of AIDS related to drug use

The second most frequent mode of HIV transmission is via blood and blood product. Blood-borne transmission will be through needle-sharing throughout endovenous drug use, needle stick injury, transfusion of contaminated blood or blood product, or medical injections with germy instrumentality. the chance from sharing a needle throughout drug injection is between zero.63 and 2.4% per act, with a median of zero.8%. the chance of getting HIV from a needle stick from AN HIV-infected person is calculable as zero.3% (about one in 333) per act and also the risk following tissue layer exposure to infected blood as zero.09% (about one in 1000) per act. within the u.  s. endovenous drug users created up twelve-tone music of all new cases of HIV in 2009, and in some aras quite eightieth of individuals United Nations agency inject medicine are HIV positive.

HIV is transmitted in concerning ninety three of blood transfusions exploitation infected blood. In developed countries the chance of getting HIV from a introduction is extraordinarily low (less than one in [*fr1] a million) wherever improved donor choice and HIV screening is performed; for instance, within the GB the chance is reported  at one in 5 million and within the u.  s. it had been one in one.5 million in 2008. In low financial gain countries, solely 1/2 transfusions could also be befittingly screened (as of 2008), and it's calculable that up to fifteen of HIV infections in these areas come back from transfusion of infected blood and blood product, representing between five-hitter and 100 percent of worldwide infections.

Unsafe medical injections play a big role in HIV unfold in geographical area. In 2007, between twelve and Revolutionary Organization 17 November of infections during this region were attributed to medical syringe use. the planet Health Organization estimates the chance of transmission as a results of a medical injection in Africa at one.2%. vital risks are related to invasive procedures, assisted  delivery, and care during this space of the planet.

People giving or receiving tattoos, piercings, and scarification ar on paper in danger of infection however no confirmed cases are documented. it's inconceivable for mosquitoes or alternative insects to transmit HIV.

Mother-to-child:
Main articles: HIV and gestation and HIV and breastfeeding
HIV will be transmitted from mother to kid throughout gestation, throughout delivery, or through breast milk. this can be the third commonest method within which HIV is transmitted globally. within the absence of treatment, the chance of transmission before or throughout birth is around two hundredth and in those that conjointly lactate thirty fifth. As of 2008, vertical transmission accounted for concerning ninetieth of cases of HIV in youngsters. With applicable treatment the chance of mother-to-child infection will be reduced to concerning one hundred and twenty fifth. Preventive treatment involves the mother taking antiretrovirals throughout gestation and delivery, AN elective cesarean delivery, avoiding breastfeeding, and administering antiretroviral medicine to the newborn. Antiretrovirals once taken by either the mother or the kid decrease the chance of transmission in those that do lactate. several of those measures ar but not out there within the developing world. If blood contaminates food throughout pre-chewing it should cause a risk of transmission.

Virology:

Main article: HIV":

Diagram of a HIV particle structure
A large spherical blue object with a smaller red object hooked up to that. Multiple tiny inexperienced spots ar flecked over each.
Scanning lepton micrograph of HIV-1, coloured inexperienced, budding from a refined leukocyte.
HIV is that the reason for the spectrum of malady referred to as HIV/AIDS. HIV may be a animal virus that primarily infects parts of the human system like CD4+ T cells, macrophages and nerve fibre cells. It directly and indirectly destroys CD4+ T cells.

HIV may be a member of the genus Lentivirus, a part of the family Retroviridae. 

Lentiviruses share several morphological and biological characteristics. several species of mammals ar infected by lentiviruses, that ar characteristically accountable for long-duration sicknesses with an extended period of time. Lentiviruses ar transmitted as fiber, positive-sense, swallowed RNA viruses. Upon entry into the target cell, the infectious agent RNA ordination is regenerate (reverse transcribed) into double-stranded DNA by a infectious agently encoded polymerase that's transported at the side of the viral ordination within the virus particle. The ensuing infectious agent DNA is then foreign into the organelle and integrated into the cellular DNA by a virally encoded integrase and host co-factors. Once integrated, the virus could become latent, permitting the virus and its host cell to avoid detection by the system. or else, the virus could also be transcribed, manufacturing new RNA genomes and infectious agent proteins that ar packaged  and discharged from the cell as new virus particles that begin the replication cycle afresh.

HIV is currently best-known to unfold between CD4+ T cells by 2 parallel routes: noncellular  unfold and cell-to-cell unfold, i.e. it employs hybrid spreading mechanisms. within the noncellular  unfold, virus particles bud from AN infected T cell, enter the blood/extracellular fluid then infect another T cell following an opportunity encounter. HIV also can broadcast by transmission mechanism from one cell to a different by a method of cell-to-cell unfold. The hybrid spreading mechanisms of HIV contribute to the virus's current replication against antiretroviral therapies.

Two kinds of HIV are characterized: HIV-1 and HIV-2. HIV-1 is that the virus that was originally discovered (and at the start brought up conjointly as toilet or HTLV-III). it's a lot of virulent, a lot of infective, and is that the reason for the bulk of HIV infections globally. The lower infectivity of HIV-2 as compared with HIV-1 implies that fewer individuals exposed to HIV-2 are infected per exposure. thanks to its comparatively poor capability for transmission, HIV-2 is basically confined to geographical area.

 Pathophysiology:

Main article: Pathophysiology of HIV/AIDS
File:HIV and AIDS explained in a very straightforward method.webm
HIV/AIDS explained in a very straightforward method
After the virus enters the body there's a amount of speedy infectious agent replication, resulting in AN abundance of virus within the peripheral blood. throughout primary infection, the extent of HIV could reach many million virus particles per ml of blood. This response is among a marked call in the amount of current CD4+ T cells. The acute viraemia is sort of invariably related to activation of CD8+ T cells, that kill HIV-infected cells, and later with protein production, or seroconversion. The CD8+ T cell response is assumed to be necessary in dominant virus levels, that peak then decline, because the CD4+ T cell counts recover. a decent CD8+ T cell response has been joined to slower malady progression and a more robust prognosis, although it doesn't eliminate the virus.

Ultimately, HIV causes AIDS by depleting CD4+ T cells. This weakens the system and permits expedient infections. T cells ar essential to the immune reaction and while not them, the body cannot fight infections or kill cancerous cells. The mechanism of CD4+ T cell depletion differs within the acute and chronic phases. throughout the acute section, HIV-induced cell lysis and killing of infected cells by cytotoxic T cells accounts for CD4+ T cell depletion, though necrobiosis can also be an element. throughout the chronic section, the implications of generalized immune activation not to mention the gradual loss of the flexibility of the system to come up with new T cells seem to account for the slow decline in CD4+ T cell numbers.

Although the symptoms of immune deficiency characteristic of AIDS don't seem for years when someone is infected, the majority of CD4+ T cell loss happens throughout the primary weeks of infection, particularly within the enteral mucous membrane, that harbors the bulk of the lymphocytes found within the body. the explanation for the discriminatory loss of tissue layer CD4+ T cells is that the bulk of tissue layer CD4+ T cells categorical the CCR5 supermolecule that HIV uses as a co-receptor to realize access to the cells, whereas solely atiny low fraction of CD4+ T cells within the blood do thus. a particular genetic modification that alters the CCR5 supermolecule once gift in each chromosomes terribly effectively prevents HIV-1 infection.

HIV seeks out and destroys CCR5 expressing CD4+ T cells throughout acute infection. an energetic immune reaction eventually controls the infection and initiates the clinically latent section. CD4+ T cells in tissue layer tissues stay significantly affected. Continuous HIV replication causes a state of generalized immune activation uninterrupted throughout the chronic section. Immune activation, that is mirrored by the increased  activation state of immune cells and unleash of pro-inflammatory cytokines, results from the activity of many HIV factor product and also the immune reaction to current HIV replication. it's conjointly joined to the breakdown of the immune closed-circuit television of the gi tissue layer barrier caused by the depletion of tissue layer CD4+ T cells throughout the acute section of malady.

 Diagnosis:

Main article: identification of HIV/AIDS
A graph with 2 lines. One in blue moves from high on the correct to low on the left with a quick rise within the middle. The second line in red moves from zero to terribly high, then drops to low and step by step rises to high once more

A generalized graph of the connection between HIV copies (viral load) and CD4+ T cell counts over the common course of untreated HIV infection.
  CD4+ T lymphocyte count (cells/mm³)
  HIV RNA copies per millilitre of plasma
HIV/AIDS is diagnosed via laboratory testing then staged supported the presence of sure signs or symptoms. HIV screening is usually recommended by the u.  s. Preventive Services Task Force for all individuals fifteen years to sixty five years getting on together with all pregnant ladies. to boot, testing is usually recommended for those at high risk, which incorporates anyone diagnosed with a sexually transmitted ill health. In several areas of the planet, a 3rd of HIV carriers solely discover they're infected at a complicated stage of the malady, once AIDS or severe immunological disorder has become apparent.

HIV testing:
Most people infected with HIV develop specific antibodies (i.e. seroconvert) at intervals 3 to 12 weeks of the initial infection. identification of primary HIV before seroconversion is completed by mensuration HIV-RNA or p24 substance. Positive results obtained by protein or PCR testing ar confirmed either by a unique protein or by PCR.

Antibody tests in youngsters younger than eighteen months ar usually inaccurate as a result of the continuing presence of maternal antibodies. therefore HIV infection will solely be diagnosed by PCR testing for HIV RNA or DNA, or via testing for the p24 substance. abundant of the planet lacks access to reliable PCR testing and lots of places merely wait till either symptoms develop or the kid is the right age for correct protein testing. In geographical area as of 2007–2009 between thirty and seventieth of the population was conscious of their HIV standing. In 2009, between 3.6 and forty second of men and girls in sub-Saharan countries were tested that delineated  a big increase compared to previous years.

Classifications:
Two main clinical staging systems ar wont to classify HIV and HIV-related malady for police work purposes: the United Nations agency malady staging system for HIV infection and malady, and also the Center for Disease Control and Prevention organization for HIV infection. The CDC's organization is a lot of oftentimes adopted in developed countries. Since the WHO's staging system doesn't need laboratory tests, it's suited to the resource-restricted conditions encountered in developing countries, wherever it also can be wont to facilitate guide clinical management. Despite their variations, the 2 systems enable comparison for applied mathematics functions.

The World Health Organization 1st planned a definition for AIDS in 1986. Since then, the United Nations agency classification has been updated and dilated many times, with the foremost recent version being printed in 2007. The United Nations agency system uses the subsequent categories:

Primary HIV infection: could also be either symptomless or related to acute retroviral syndrome.
Stage I: HIV infection is symptomless with a CD4+ T cell count (also referred to as CD4 count) bigger than five hundred per microlitre (µl or solid mm) of blood. could embody generalized node enlargement.
Stage II: gentle symptoms which can embody minor connective tissue manifestations and perennial higher tract infections. A CD4 count of but 500/µl.
Stage III: Advanced symptoms which can embody unexplained chronic looseness of the bowels for extended than a month, severe microorganism infections together with T.B. of the respiratory organ, and a CD4 count of but 350/µl.
Stage IV or AIDS: severe symptoms that embody infection of the brain, fungal infection of the passage, trachea, bronchi or lungs and Kaposi's sarcoma. A CD4 count of but 200/µl.
The u.  s. Center for malady management and hindrance conjointly created a organization for HIV, and updated it in 2008 and 2014. this method classifies HIV infections supported CD4 count and clinical symptoms, and describes the infection in 5 teams. In those bigger than six years getting on it is:

Stage 0: the time between a negative or indeterminate HIV check followed but one hundred eighty days by a positive check
Stage 1: CD4 count ≥ five hundred cells/µl and no AIDS process conditions
Stage 2: CD4 count two hundred to five hundred cells/µl and no AIDS process conditions
Stage 3: CD4 count ≤ two hundred cells/µl or AIDS process conditions
Unknown: if meagerly info is on the market to form any of the on top of classifications
For police work functions, the AIDS identification still stands even though, when treatment, the CD4+ T cell count rises to on top of two hundred per µL of blood or alternative AIDS-defining sicknesses ar cured.

 https://en.wikipedia.org/wiki/HIV/AIDS