HIV/AIDS Warning: You are not logged in. Your IP address will be publicly visible if you make any edits. If you log in or create an account, your edits will be attributed to your username, along with other benefits.Anti-spam check. Do not fill this in! AdvancedSpecial charactersHelpHeadingLevel 2Level 3Level 4Level 5FormatInsertLatinLatin extendedIPASymbolsGreekGreek extendedCyrillicArabicArabic extendedHebrewBanglaTamilTeluguSinhalaDevanagariGujaratiThaiLaoKhmerCanadian AboriginalRunesÁáÀàÂâÄäÃãǍǎĀāĂ㥹ÅåĆćĈĉÇçČčĊċĐđĎďÉéÈèÊêËëĚěĒēĔĕĖėĘęĜĝĢģĞğĠġĤĥĦħÍíÌìÎîÏïĨĩǏǐĪīĬĭİıĮįĴĵĶķĹĺĻļĽľŁłŃńÑñŅņŇňÓóÒòÔôÖöÕõǑǒŌōŎŏǪǫŐőŔŕŖŗŘřŚśŜŝŞşŠšȘșȚțŤťÚúÙùÛûÜüŨũŮůǓǔŪūǖǘǚǜŬŭŲųŰűŴŵÝýŶŷŸÿȲȳŹźŽžŻżÆæǢǣØøŒœßÐðÞþƏəFormattingLinksHeadingsListsFilesDiscussionReferencesDescriptionWhat you typeWhat you getItalic''Italic text''Italic textBold'''Bold text'''Bold textBold & italic'''''Bold & italic text'''''Bold & italic textDescriptionWhat you typeWhat you getReferencePage text.<ref>[https://www.example.org/ Link text], additional text.</ref>Page text.[1]Named referencePage text.<ref name="test">[https://www.example.org/ Link text]</ref>Page text.[2]Additional use of the same referencePage text.<ref name="test" />Page text.[2]Display references<references />↑ Link text, additional text.↑ Link text== Diagnosis == {{Main|Diagnosis of HIV/AIDS}} [[File:Hiv-timecourse.png|thumb|upright=1.35|alt=A graph with two lines. One in blue moves from high on the right to low on the left with a brief rise in the middle. The second line in red moves from zero to very high then drops to low and gradually rises to high again|A generalized graph of the relationship between HIV copies (viral load) and CD4<SUP>+</SUP> T cell counts over the average course of untreated HIV infection: {{legend-line|blue solid 2px|CD4<sup>+</sup> T Lymphocyte count (cells/mm³)}} {{legend-line|red solid 2px|HIV RNA copies per mL of plasma}}]] {| class="wikitable floatright" |+Days after exposure needed for the test to be accurate<ref>{{cite web |url=https://www.cdc.gov/hiv/basics/testing.html |title=HIV/AIDS Testing |date=March 16, 2018 |website=U.S. [[Centers for Disease Control and Prevention]] (CDC) |access-date=April 14, 2018 |archive-url=https://web.archive.org/web/20180414234419/https://www.cdc.gov/hiv/basics/testing.html |archive-date=April 14, 2018 |url-status=live }}</ref> !Blood test !Days |- |Antibody test <small>(rapid test, [[ELISA]] 3rd gen)</small> |23–90 |- |Antibody and p24 antigen test <small>(ELISA 4th gen)</small> |18–45 |- |PCR |10–33 |} HIV/AIDS is diagnosed via laboratory testing and then staged based on the presence of [[AIDS defining clinical condition|certain signs or symptoms]].<ref name=WHOCase2007/> HIV screening is recommended by the [[United States Preventive Services Task Force]] for all people 15 years to 65 years of age, including all pregnant women.<ref name=USP2019Screen>{{cite journal |last1=US Preventive Services Task |first1=Force |last2=Owens |first2=DK |last3=Davidson |first3=KW |last4=Krist |first4=AH |last5=Barry |first5=MJ |last6=Cabana |first6=M |last7=Caughey |first7=AB |last8=Curry |first8=SJ |last9=Doubeni |first9=CA |last10=Epling JW |first10=Jr |last11=Kubik |first11=M |last12=Landefeld |first12=CS |last13=Mangione |first13=CM |last14=Pbert |first14=L |last15=Silverstein |first15=M |last16=Simon |first16=MA |last17=Tseng |first17=CW |last18=Wong |first18=JB |title=Screening for HIV Infection: US Preventive Services Task Force Recommendation Statement. |journal=JAMA |date=June 18, 2019 |volume=321 |issue=23 |pages=2326–2336 |doi=10.1001/jama.2019.6587 |pmid=31184701|doi-access=free }}</ref> Additionally, testing is recommended for those at high risk, which includes anyone diagnosed with a sexually transmitted illness.<ref name=Deut2010/><ref name=USP2019Screen/> In many areas of the world, a third of HIV carriers only discover they are infected at an advanced stage of the disease when AIDS or severe immunodeficiency has become apparent.<ref name=Deut2010/> === HIV testing === [[File:HIV Rapid Test being administered.jpg|thumb|HIV rapid test being administered]] [[File:Oraquick.jpg|thumb|Oraquick HIV test]] Most people infected with HIV develop [[seroconvert]]ed (antigen-specific) [[antibodies]] within three to twelve weeks after the initial infection.<ref name=M118/> Diagnosis of primary HIV before seroconversion is done by measuring HIV-[[RNA]] or [[Diagnosis of HIV/AIDS#Antigen tests|p24 antigen]].<ref name=M118/> Positive results obtained by antibody or [[Polymerase chain reaction|PCR]] testing are confirmed either by a different antibody or by PCR.<ref name=WHOCase2007/> Antibody tests in children younger than 18 months are typically inaccurate, due to the continued presence of [[Maternal Passive Immunity#Naturally acquired passive immunity|maternal antibodies]].<ref name=ChildDiag2010>{{cite journal |vauthors=Kellerman S, Essajee S |title=HIV testing for children in resource-limited settings: what are we waiting for? |journal=[[PLOS Medicine]] |volume=7 |issue=7 |page=e1000285 |date=July 2010 |pmid=20652012 |pmc=2907270 |doi=10.1371/journal.pmed.1000285 |doi-access=free }}</ref> Thus HIV infection can only be diagnosed by PCR testing for HIV RNA or DNA, or via testing for the p24 antigen.<ref name=WHOCase2007/> Much of the world lacks access to reliable PCR testing, and people in many places simply wait until either symptoms develop or the child is old enough for accurate antibody testing.<ref name=ChildDiag2010/> In sub-Saharan Africa between 2007 and 2009, between 30% and 70% of the population were aware of their HIV status.<ref name=UN2011Eighty>UNAIDS 2011 pg. 70–80</ref> In 2009, between 3.6% and 42% of men and women in sub-Saharan countries were tested;<ref name=UN2011Eighty/> this represented a significant increase compared to previous years.<ref name=UN2011Eighty/> ===Classifications=== Two main clinical staging systems are used to classify HIV and HIV-related disease for [[Disease surveillance|surveillance]] purposes: the [[WHO disease staging system for HIV infection and disease]],<ref name=WHOCase2007/> and the [[CDC classification system for HIV infection]].<ref name=CDCCase2008/> The CDC's classification system is more frequently adopted in developed countries. Since the WHO's staging system does not require laboratory tests, it is suited to the resource-restricted conditions encountered in developing countries, where it can also be used to help guide clinical management. Despite their differences, the two systems allow a comparison for statistical purposes.<ref name=M121/><ref name=WHOCase2007/><ref name=CDCCase2008/> The World Health Organization first proposed a definition for AIDS in 1986.<ref name=WHOCase2007/> Since then, the WHO classification has been updated and expanded several times, with the most recent version being published in 2007.<ref name=WHOCase2007>{{cite book |title=WHO case definitions of HIV for surveillance and revised clinical staging and immunological classification of HIV-related disease in adults and children |pages=6–16 |url=https://www.who.int/hiv/pub/guidelines/HIVstaging150307.pdf |year=2007 |publisher=World Health Organization |location=Geneva |isbn=978-92-4-159562-9 |url-status=live |archive-url=https://web.archive.org/web/20131031044253/http://www.who.int/hiv/pub/guidelines/HIVstaging150307.pdf |archive-date=October 31, 2013 }}</ref> The WHO system uses the following categories: * Primary HIV infection: May be either asymptomatic or associated with acute retroviral syndrome<ref name=WHOCase2007/> * Stage I: HIV infection is [[asymptomatic]] with a CD4<SUP>+</SUP> T cell count (also known as CD4 count) greater than 500 per microlitre (µl or cubic mm) of blood.<ref name=WHOCase2007/> May include generalized lymph node enlargement.<ref name=WHOCase2007/> * Stage II: Mild symptoms, which may include minor [[Mucous membrane|mucocutaneous]] manifestations and recurrent [[upper respiratory tract infection]]s. A CD4 count of less than 500/µl<ref name=WHOCase2007/> * Stage III: Advanced symptoms, which may include unexplained [[Chronic (medical)|chronic]] diarrhea for longer than a month, severe bacterial infections including tuberculosis of the lung, and a CD4 count of less than 350/µl<ref name=WHOCase2007/> * Stage IV or AIDS: severe symptoms, which include [[toxoplasmosis]] of the brain, [[candidiasis]] of the [[esophagus]], [[trachea]], [[bronchi]], or [[lung]]s, and [[Kaposi's sarcoma]]. A CD4 count of less than 200/µl<ref name=WHOCase2007/> The U.S. Centers for Disease Control and Prevention also created a classification system for HIV, and updated it in 2008 and 2014.<ref name=CDCCase2008>{{cite journal |vauthors=Schneider E, Whitmore S, Glynn KM, Dominguez K, Mitsch A, McKenna MT |title=Revised surveillance case definitions for HIV infection among adults, adolescents, and children aged <18 months and for HIV infection and AIDS among children aged 18 months to <13 years – United States, 2008 |journal=MMWR. Recommendations and Reports |volume=57 |issue=RR-10 |pages=1–12 |date=December 2008 |pmid=19052530 |url=https://www.cdc.gov/mmwr/PDF/rr/rr5710.pdf |access-date=October 17, 2020 |archive-date=October 17, 2020 |archive-url=https://web.archive.org/web/20201017160943/https://www.cdc.gov/mmwr/PDF/rr/rr5710.pdf |url-status=live }}</ref><ref name=CDC2014Clas>{{cite journal |title=Revised surveillance case definition for HIV infection – United States, 2014 |journal=MMWR. Recommendations and Reports |volume=63 |issue=RR-03 |pages=1–10 |date=April 2014 |pmid=24717910 |author1=Centers for Disease Control Prevention (CDC) |url=https://www.cdc.gov/mmwr/pdf/rr/rr6303.pdf |access-date=October 17, 2020 |archive-date=October 17, 2020 |archive-url=https://web.archive.org/web/20201017133412/https://www.cdc.gov/mmwr/pdf/rr/rr6303.pdf |url-status=live }}</ref> This system classifies HIV infections based on CD4 count and clinical symptoms, and describes the infection in five groups.<ref name=CDC2014Clas/> In those greater than six years of age it is:<ref name=CDC2014Clas/> * Stage 0: the time between a negative or indeterminate HIV test followed less than 180 days by a positive test * Stage 1: CD4 count ≥ 500 cells/µl and no AIDS-defining conditions * Stage 2: CD4 count 200 to 500 cells/µl and no AIDS-defining conditions * Stage 3: CD4 count ≤ 200 cells/µl or AIDS-defining conditions * Unknown: if insufficient information is available to make any of the above classifications. For surveillance purposes, the AIDS diagnosis still stands even if, after treatment, the CD4<SUP>+</SUP> T cell count rises to above 200 per µL of blood or other AIDS-defining illnesses are cured.<ref name="M121"/> Summary: Please note that all contributions to Christianpedia may be edited, altered, or removed by other contributors. If you do not want your writing to be edited mercilessly, then do not submit it here. You are also promising us that you wrote this yourself, or copied it from a public domain or similar free resource (see Christianpedia:Copyrights for details). Do not submit copyrighted work without permission! Cancel Editing help (opens in new window) Discuss this page