AIDS (acquired immunodeficiency syndrome) is a stage of HIV infection in which an infected person's immune system has grown so weak that he or she is in danger of getting (or has already developed) additional infectionsor malignanciesthat might potentially ead todeath.
Though all persons with AIDS are infected with HIV-1, not all people with HIV-1 infection have AIDS, and not all peoplewithHIV-1 infectionwill acquireAIDS.
HIV
Pathogenesis
Human immunodeficiency virus-1 (HIV-1), a member of the retrovirus family, is the cause of AIDS. Retroviruses are ribonucleic acid (RNA) viruses with an enzyme (reverse transcriptase) that converts viral RNA to deoxyribonucleicacid (DNA).
In the case of HIV-1, this DNA (now known as a DNA provirus) is then integrated into the DNA of the infected individual. When the DNA of the infected individual is transcribed, or read, by the cell's molecular machinery, theproviral DNAisalsoread,resulting inthegenerationof a newvirusand itsdischargefromthe nfected cell.
HIV-1 infection pathogenesis is complicated. HIV-1 interacts with cells with certain types of molecular receptors, such as CD4 and chemokine receptors. CD4 lymphocytes, macrophages, and microglial cells in the brainall carrythesereceptors.
CD4 cells are a kind of T-cell helper. Macrophages are immune cells that eat infected cells, while microglial cellsareimmunecellsthat fulfill variousactivitiesinthebrain.
Theviruswill multiplyafter binding and entering thecell,aspreviouslyexplained. Inaninfected person,up to10 billionvirusesand particlescanbecreated ina singleday.
Oneof HIV-1'sprimarytargetsisCD4 cells. Thesecellsarecritical to theimmunesystem'soperation Direct viral death, other lymphocytes that destroy HIV-infected cells, and maybe additional processes all contribute to thedestructionof CD4 lymphocytes.
When CD4 cells are reduced, the immune system's capacity to combat infections and some malignancies is compromised. Theseinfectionsand malignanciescan emergewhen thelossissevereenough, and theycan kill theHIV-infected individual.
Medical specialistsbelievethat theinfected personhasfull-blownAIDSat thislevel of reduced CD4 cells.
Transmission
Theepidemiologyof HIVinfectionand AIDShasevolved over time.
Males who had sex with men were by far the most impacted risk group when the illness was first diagnosed in the early 1980s, followed by intravenous drug users who shared needles, those who got HIV-contaminated blood,and hemophiliacswhoreceived infected clotting factors.
Women who had sexual contact with HIV-positive males were identified as being at high risk of getting the virusand,if pregnant,passing it ontotheir unbornchildren.
Though this diseasewas originallyidentified in theUnited States, instances quicklyspread to other parts of the world. Sub-Saharan Africa, the Caribbean, and Asia were particularly heavily struck. At the turn of the century, it is believed that more than forty million individuals worldwide are infected, with as many as one million in the United Statesalone.
HIV-1 is transmitted by contaminated body fluids. By far the most prevalent mechanism of HIV transmission is sexual interaction.Anal intercourseisthemost effectivesexual method of spreading thevirus.
The second biggest risk is vaginal intercourse, which is more dangerous for women than for men. In other words, an infected man infecting a woman through penile-vaginal intercourse is simpler than the other way around,especiallyif theguyiscircumcised and hasnosoresor ulcersonhispenis.
Because HIV is a blood-borne illness, those who use intravenous drugs and share needles can readily spread the virus in this way. There was a danger of contracting HIV by transfusion of blood or a blood product before testing for thevirusintheblood supply,but thisrisk isnowextremelylow. Vertical transmission, or transfer frommother to child during pregnancy, happens in approximately one-third of HIV-infected pregnant womenwhoarenot onanti-HIVdrugs.
Prevention HIVtransmissionpreventionisbotha behavioral and a medical issue.
The only definite way to avoid HIV transmission is to abstain from sexual activity. Though this is correct, premarital and extramarital sexual conduct iswidespread inmost civilizations.
Condomsact asan efficient barrier against sexual transmission. Social, religious, political, and cultural factors, on the other hand, intrude into condom education for teenagers and contribute to debates over sexual behavior education in general. With one-third or more of HIV infections happening in youth, vigorous and truthful teaching efforts are required. Only by understanding the implications and knowing how to avoid transmissioncanonemakeaneducated decisionregarding one'sactions.
Asidefromall of this,therearemedical aspects otransmissionprevention.
As previously stated, HIV-infected pregnant women who are treated with anti-HIV drugs can lower their chanceof passing theinfectiontotheir unbornchild.
Using anti-HIV drugs, healthcare workers who are poked with needles tainted with blood from HIV-positive patientscanlower their risk of infection.
In the early twenty-first century, medical research looked at the idea of lowering the risk of HIV transmission following a sexual interaction bytreating theuninfected contact with anti-HIVdrugs. Vaccinesagainst HIVare being developed invariouscountriesof theworld,but haveyet tobeproventobeeffective.
Treatment
HIV/AIDS treatment is both hard and costly. The existing drugs suppress the reverse transcriptase enzyme as well asanenzymethat helpsthevirusgrowintoonethat caninfect additional cells.
A combination of at least three distinct drugs acting at these multiple locations can entirely rid the bloodstreamof a virus. After treatment, thepatient's immune systemusually improves and, in somesituations, returnstonormal.
If the patient takes the medications as prescribed and the virus is suppressed, the patient may never become ill.However,thevirusisstill present inlymphnodesand maybeother organs.
If the patient quits taking his or her drugs or takes theminconsistently, the virus will re-enter circulation. Once the virus is created again, it is quite likely that it will evolve into a formthat is resistant to the treatments that thepatient waspreviouslytaking.
When this happens, especially if the patient has been on more than one pharmaceutical regimen, a virus that isresistant toall existing therapiesmight bechosen.
There isn't much more that can be done at this time One big issue concerning these people is that if they continue to be sexually active or use needles, they will spread resistant viruses. This is becoming increasingly widelyreported.
New drugs are being researched to see whether they may solve the resistance problem by addressing new locationsof viral productionor thosethat areunaffected bychangesintheresistant virus.
The difficulties here include the chance that the patient may die before the new drugs are ready; that if the patient survives, he or she will be unable to bear the new medicines' adverse effects; and, lastly, that the patient will beunabletopayfor themedicines.
In theUnited States, anti-HIVor anti-retroviral drugscost morethan $10,000a year. This, along with thepriceof blood testing and medical visits, puts therapy out of reach for the vast majority of infected individuals worldwide.
HIV/AIDSisand will remainoneof themost difficult medical difficultiesthat medical practitionershaveever confronted.Publichealthexpertspresentlyhaveonlypreventionand educationtousetostop thetideof an ever-growing disease.
