Hiv: Human retrovirus, cause of AIDS

Human immunodeficiency virus (HIV) is a type of virus called a Lentivirus.

This is a kind of retrovirus. It infects the human immune system, which is the system in the body which fights off infections.

Human immunodeficiency viruses
Scanning electron micrograph of HIV-1 (in green) budding from cultured lymphocyte. Multiple round bumps on cell surface represent sites of assembly and budding of virions.
Scanning electron micrograph of HIV-1 (in green) budding from cultured lymphocyte. Multiple round bumps on cell surface represent sites of assembly and budding of virions.
Scientific classificationEdit this classification
(unranked): Virus
Realm: Riboviria
Kingdom: Pararnavirae
Phylum: Artverviricota
Class: Revtraviricetes
Order: Ortervirales
Family: Retroviridae
Subfamily: Orthoretrovirinae
Genus: Lentivirus
Groups included
  • Human immunodeficiency virus 1
  • Human immunodeficiency virus 2
Other lentiviruses
  • Bovine immunodeficiency virus
  • Caprine arthritis encephalitis virus
  • Equine infectious anemia virus
  • Feline immunodeficiency virus
  • Jembrana disease virus
  • Puma lentivirus
  • Simian immunodeficiency virus
  • Visna-maedi virus
HIV and AIDS explained in a simple way
Hiv: How people get infected, Treatment, PREP
Percentage of adults that are infected with HIV per country at the end of 2005
  15–50% (15-50 people out of 100)
  5–15% (5-15 people out of 100)
  1–5% (1-5 people out of 100)
  0.5–1.0% (1-2 people out of 200)
  0.1–0.5% (1-5 people out of 1000)
  <0.1% (less than 1 person out of 1000)
  Greenland no data
Hiv: How people get infected, Treatment, PREP
Diagram of the immature and mature forms of HIV

HIV may cause AIDS. This kills the white blood cells which a healthy body uses to fight diseases.

How people get infected

A person can get infected with HIV if any body liquid with the virus gets into their body. The body liquids that carry HIV are blood, semen, liquid from the vagina, and breast milk.

The virus may get into the body through injured skin. More usually it gets in through the mouth, eyes, nose, vagina, anus, or penis.

However, when people get HIV by having sex, the virus may enter the body through the vagina or anus.

There are some common ways to get HIV:

  • A person with HIV can give a sexual partner the virus if they have unprotected sex. That means having sexual intercourse without a condom.
  • A person can get HIV if he or she uses the same needle as a person with HIV to inject drugs or get a tattoo.
  • A person may get HIV if he or she is stuck by a needle that was used on a patient with HIV.
  • Babies can get the virus from their mothers when they are born or when they are breastfeeding. A baby may be protected from getting HIV this way if their mother takes certain medications while she is pregnant.
  • Blood transfusions using infected blood products was a common cause of HIV. The blood had been taken from people with HIV infections. Now, in the developed world screening of blood products for HIV has mostly stopped this happening. However, people may still get HIV from blood transfusions in less-developed countries if the blood is not screened.

A person cannot get infected with HIV from non-sexual touching, like a hug or handshake, or touching someone else's saliva. A person cannot get HIV from an insect bite, a cough, or a sneeze. People also cannot get HIV from touching light switches, using toilets, or drinking from the same glass as a person with HIV.

Data

Comparison of HIV species
Species Virulence Infectivity Prevalence Inferred origin
HIV-1 High High Global Common Chimpanzee
HIV-2 Lower Low West Africa Sooty Mangabey


Estimated per-act risk for acquisition of HIV by exposure route
Exposure Route Estimated infections per 10,000 exposures to an infected source
Blood transfusion
[Being given blood in a transfusion]
9,000 (90%)
Mother-to-child, including pregnancy, childbirth and breastfeeding (without treatment)
[Mother giving her child or unborn child HIV, if she does not take medications to prevent giving the child HIV]
2,500 (25%)
Mother-to-child, including pregnancy, childbirth and breastfeeding (with optimal treatment)
[Mother giving her child or unborn child HIV, if she takes the best possible medications to prevent giving the child HIV]
100–200 (1%–2%)
Needle-sharing injection drug use
[People sharing the same needle to inject illegal drugs]
67 (0.67%)
Percutaneous needle stick
[Getting stuck by a needle used on a person with HIV - for example, in healthcare]
30 (0.30%)
Receptive anal intercourse (2009 and 2010 studies)
[Receiving anal sex]
170 (1.7%) [30–890] / 143 [48–285]
Receptive anal intercourse (based on data of a 1992 study)
[Receiving anal sex]
50 (0.5%)
Insertive anal intercourse for uncircumcised men (2010 study)
[An uncircumsized man giving anal sex]
62 (0.62%)a [7–168]
Insertive anal intercourse for circumcised men (2010 study)
[A circumsized man giving anal sex]
11 (0.11%)a [2–24]
Insertive anal intercourse (based on data of a 1992 study)
[Giving anal sex]
6.5 (0.065%)
Low-income country female-to-male
[A woman giving a man HIV through sexual activity; rate is for low-income countries]
38 (0.38%) [13–110]
Low-income country male-to-female
[A man giving a woman HIV through sexual activity; rate is for low-income countries]
30 (0.3%) [14–63]
Receptive (female) penile-vaginal intercourse
[A woman receiving sexual intercourse from a man]
10 (0.1%)
Insertive (male) penile-vaginal intercourse
[A man giving sexual intercourse to a woman]
5 (0.05%)
Fellating a man
[Performing oral sex on a man]
1 (0.01%)b
Man being fellated
[A man receiving oral sex]
0.5 (0.005%)b
    a Other studies found insufficient evidence that male circumcision protects against HIV infection among men who have sex with men
    b Oral trauma, sores, inflammation, concomitant sexually transmitted infections, ejaculation in the mouth, and systemic immune suppression may increase HIV transmission rate.
    "best-guess estimate"
    Pooled transmission probability estimate.
    Bracketed values represent 95% confidence interval.

Treatment

Drug treatment

HIV causes a person to become more prone to illness, so infected people need treatment options. However, there is no cure for HIV. To help ease negative symptoms, drugs called anti-retroviral therapy (ART) are available. This treatment is also called high active anti-retroviral therapy (HAART). HAART treatment begins with one non-nucleoside reverse transcriptase inhibitor (NNRTI) and two nucleoside analogue reverse transcriptase inhibitors (NRTIs). The NRTI drug could be named zidovudine (AZT), tenofovir (TDF), andlamivudine (3TC), or emtricitabine (FTC).

These drugs slow the progression of the HIV virus in the body. Usually, these treatments consist of a combination of three or more drugs, and each drug performs a different job in fighting the virus. In general, HAART prevents the HIV from multiplying and destroying CD4 cells. CD4 cells are necessary to help protect the body from infections and cancer. Since the HIV virus destroys CD4 cells, it causes people with HIV to be more prone to illness.

It is recommended to start HAART if a person has HIV and has a CD4 cell count of less than or equal to 350 cells/mm3. This number can be determined by a doctor. A person’s age, sex, and other infections determine which treatment he or she should take. These medication regimens can help HIV-infected people live longer, healthier lives, and can also help prevent the HIV from advancing to AIDS.

Hiv: How people get infected, Treatment, PREP 
Symptoms of acute HIV infection

General treatment

There has been controversy surrounding when the correct time to start therapy should be after a person discovers that he or she has HIV. Recently, the answer has been that earlier treatment is recommended. This is because, first, effective therapy can prevent non-AIDS-related deaths. Second, therapy can prevent harm to a person’s immune system. Third, therapy can help prevent transmission of HIV to others, and can therefore reduce HIV prevalence overall. Although there are some negative side effects of antiretroviral medications, the benefits of therapy usually outweigh the negative effects.

Effects of therapy

Patients on HAART have reported significant improvements in physical health, emotional health, mental health, and daily function compared to HIV-positive patients not yet on treatment. Most research has occurred in developing countries, and little research has been done on the impacts of ART on household wellbeing.

Although HAART can be an effective means to treating HIV, there can be many negative side effects. Negative side effects can vary by drug, by ethnicity, and by drug interactions in the body. The following list contains the most common and serious negative side effects associated with HAART medications to treat HIV.

Nucleoside Reverse Transcriptase Inhibitors (NRTIs)

Nonnucleoside Reverse Transcriptase Inhibitors (NNRTIs)

Protease Inhibitors (PIs)

Fusion Inhibitors

  • Injection site reactions, neutropenia, increased frequency of pneumonia

Chemokine Coreceptor Antagonists

Integrase Inhibitors

  • Nausea, diarrhea, headache, rash

Pharmacokinetic Enhancers

  • Increased serum creatinine, proteinuria, nausea, diarrhea

Alternative therapy

Many people living with HIV have tried using alternative treatment methods, known as complementary and alternative medicine (CAM). Some types of CAM include stress management, natural health products, massage/therapeutic touch, acupuncture, and homeopathy. Stress management can increase quality of life for a person with HIV. Even with little evidence of its effectiveness, many people chose to try CAM because of the many negative side effects associated with HAART and the few negative side effects associated with CAM. Some HIV-infected people also try herbal medicines to treat HIV, but there has been no evidence showing any positive outcomes with the use of herbal remedies.

Another type of alternative therapy for treating HIV is micronutrient supplementation. Micronutrients are vitamins and minerals, so these supplements would be in the form of a general daily multivitamin. These supplements have been proven to help treat HIV because HIV can cause micronutrient deficiencies, so the supplements can help replenish these needed vitamins and minerals. Although the supplements may not help ease all negative symptoms, they offer some benefits and are safe for HIV-infected patients. Supplements are also safe for HIV-infected pregnant women and their children. Specifically, vitamin A and zinc have shown positive health effects. There are no major negative side effects of vitamin and mineral supplements.

Alternative therapies can help to reduce symptoms of diseases like HIV, but do not cure the disease, or stop the disease from spreading to other people.

PREP

"PREP" or "PrEP" is pre-exposure prophylaxis. This means a person takes a drug before having risky sex. The drug 'Truvada' is a combination of two different anti-viral treatments: tenofovir and emtricitabine. Truvada is very expensive, and was not available on the UK's National Health Service before 2016. A study, published in The Lancet in 2023 found that PrEP reduced the chances of getting HIV by almost 87% and recommended that it should be more easily available.

References

Other websites

Tags:

Hiv How people get infectedHiv TreatmentHiv PREPHiv Other websitesHivImmune systemInfectionLentivirusRetrovirusVirus

🔥 Trending searches on Wiki Simple English:

List of countries and dependencies by population densityGrassAlbert EinsteinMetric tonTildeShraddha KapoorThe Avengers (movie)EuropeBaguioHugo TraversOctoberPalm treeTriple HList of European countries by areaRaccoonMartin Luther King Jr.United StatesList of figures in Greek mythologyList of animal phylaOral sexJacqueline FernandezSubject (school)CholeraPakistanPostal codes in GermanyNudityBangladeshRepublican Party (United States)Greek numerals2029List of districts of Andhra PradeshList of cities in ItalyProfessorOrgasmSunda Island tigerWarrior (wrestler)Colon (punctuation)Korean languageKGBNarendra Modi17 (number)Battle of UhudRevolution (2024)R. Budd DwyerDeep-throatingFarmingFreddie MercuryList of districts of Uttar PradeshLanguages of SingaporeColourRik MayallLa Liga Filipina2020OceaniaLondonGuardians of the Galaxy Vol. 3George MichaelRabbitPlantainVic SottoIra EinhornCanuckPortuguese languageJay-Jay OkochaBrock LesnarIron Man 3The Shawshank Redemption2022 UEFA Champions League FinalZodiacCaliforniaOlivia RodrigoQWERTYConstitutional republic🡆 More