HIV stands for human immunodeficiency virus. It is the virus that can lead to acquired immunodeficiency syndrome or AIDS if not treated. Unlike some other viruses, the human body can’t get rid of HIV completely, even with treatment. So once you get HIV, you have it for life.
Human Immunodeficiency Virus (HIV) infection, the cause of Acquired Immune Deficiency Syndrome (AIDS) has become a significant threat to global public health faster than any previous epidemic (Mann and Tarantola 1996). The genetic nature of HIV evades the development of a preventive vaccine and a cure for HIV infection remains a distant hope. HIV is transmitted through direct contact with HIV infected blood, semen, and vaginal secretions. Although HIV is transmitted during birth from mother-to-infant and through contaminated blood products the majority of AIDS cases in the world have resulted from HIV transmission between adults engaged in high-risk practices. Behavioral interventions therefore remain the most realistic means for curtailing the spread of HIV infection. Effective HIV risk reduction interventions target two principle behaviors: (a) sharing HIV contaminated drug injection equipment and (b) decreasing exposure to HIV infected semen, vaginal secretions, and sexually derived blood. Interventions to change injection equipment sharing and high-risk sexual practices can, therefore, dramatically effect the spread of HIV. In this article, factors associated with HIV transmission risks and interventions directed at reducing risks associated with injection drug use and sexual relations are examined.
Most individuals infected with HIV will progress to AIDS if not treated. However, there is a tiny subset of patients who develop AIDS very slowly, or never at all. These patients are called non-progressors.
People with AIDS have had their immune system damaged by HIV. They are at very high risk of getting infections that are uncommon in people with a healthy immune system. These infections are called opportunistic infections. These can be caused by bacteria, viruses, fungi, or protozoa, and can affect any part of the body. People with AIDS are also at higher risk for certain cancers, especially lymphomas and a skin cancer called Kaposi sarcoma.
Pregnant women who are HIV-positive should seek care immediately from an obstetrician (OB). ART reduces the risk of transmitting the virus to the fetus, and the mother may be treated by both the OB and an infectious-disease subspecialist. Therapy can also be given during childbirth, or perinatal period, in order to help prevent HIV infection in the newborn. There are certain drugs, however, that are harmful to the baby. Therefore, seeing a physician as early as possible before or during pregnancy to discuss ART medications is crucial.
Your doctor can monitor how well your HIV treatment is working by measuring the amount of HIV in your blood (also called the viral load.) The goal of treatment is to get the viral load undetectable on labs tests; ideally less than 20 copies. This does not mean the virus is gone or cured, it means the medication is working and must be continued.
There is no fixed site of integration, but the virus tends to integrate in areas of active transcription, probably because these areas have more open chromatin and more easily accessible DNA. [58, 59] This greatly complicates eradication of the virus by the host, as latent proviral genomes can persist without being detected by the immune system and cannot be targeted by antivirals. See the image below.
No firm evidence has shown that the initiation of therapy early in the asymptomatic period is effective. However, very late initiation is known to result in a less effective response to therapy and a lower level of immune reconstitution.
The proviral reservoir, as measured by DNA polymerase chain reaction (PCR), seems to be incredibly stable. Although it does decline with aggressive antiviral therapy, the half-life is such that eradication is not a viable expectation.
[Guideline] World Health Organization. Scaling up antiretroviral therapy in resource-limited settings: Treatment guidelines for a public health approach: 2003 revision. World Health Organization, Geneva 2004. Available at http://www.who.int/hiv/pub/prev_care/en/arvrevision2003en.pdf.
In June, the first reports of AIDS in children hinted that it could be passed via casual contact but this was later ruled out and it was concluded that they had probably directly acquired AIDS from their mothers before, during or shortly after birth.17
HIV attacks the body’s immune system, specifically the CD4 cells (T cells), which help the immune system fight off infections. Untreated, HIV reduces the number of CD4 cells (T cells) in the body, making the person more likely to get other infections or infection-related cancers.
Centers for Disease Control and Prevention. Monitoring selected national HIV prevention and care objectives by using HIV surveillance data—United States and 6 U.S. dependent areas—2010. HIV Surveillance Supplemental Report 2012;17(No. 3, part A). Atlanta (GA): CDC; 2012. Available at: http://www.cdc.gov/hiv/pdf/statistics_2010_HIV_Surveillance_Report_vol_17_no_3.pdf. Retrieved December 11, 2013. ⇦
In 2015, among 1,122,900 persons living with HIV infection, 162,500 (14.5%) were unaware of their infection. The percentage of undiagnosed HIV infections ranged from 5.7% to 18.5% across states (Figure 1); 50.5% of undiagnosed infections were in the South. Among 39,720 persons with HIV infection diagnosed in 2015, 21.6% had stage 3 infection (AIDS) at the time of diagnosis, and the estimated median interval from HIV infection to diagnosis was 3.0 years (Table 1). Diagnosis delays were longer among persons who were older at diagnosis than among those who were younger (median = 4.5 years among persons aged ≥55 years compared with 2.4 years among persons aged 13–24 years) (p<0.01). By race/ethnicity, median diagnosis delay ranged from 2.2 years among whites to 4.2 years among Asians (p<0.01). Diagnosis delay was longer among males (median = 3.1 years) than among females (median = 2.4 years) (p<0.01). By transmission category, diagnosis delay was longest among males with infection attributed to heterosexual contact (median = 4.9 years). The dimerization, packaging, and gene-transcription processes are intimately linked; disruption in one process often subsequently affects another. The LTRs exist only in the proviral DNA genome; the viral RNA genome contains only part of each LTR, and the complete LTRs are re-created during the reverse-transcription process prior to integration into the host DNA. "He was immediately put on treatment, strong antiviral drugs, which has suppressed the virus, to the point that he is absolutely healthy from that vantage," Huizenga said. "Individuals who are optimally treated with undetectable viral loads, (the risk is) incredibly low to transmit the virus. We can't say it's zero, but it's an incredibly low number." In 2016 about 36.7 million people were living with HIV and it resulted in 1 million deaths. There were 300,000 fewer new HIV cases in 2016 than in 2015. Most of those infected live in sub-Saharan Africa. Between its discovery and 2014 AIDS has caused an estimated 39 million deaths worldwide. HIV/AIDS is considered a pandemic—a disease outbreak which is present over a large area and is actively spreading. HIV is believed to have originated in west-central Africa during the late 19th or early 20th century. AIDS was first recognized by the United States Centers for Disease Control and Prevention (CDC) in 1981 and its cause—HIV infection—was identified in the early part of the decade. Acquired immune deficiency syndrome (AIDS) is caused by infection with the human immunodeficiency virus (HIV), which destroys a certain type of T lymphocyte, the helper T cell. An infected individual is susceptible to a variety of infectious organisms, including those called opportunistic pathogens, which may live benignly in the… A single case report detailed a possible cure resulting from stem-cell transplantation from a CCR5-delta32 homozygous donor (performed to treat acute myelocytic leukemia). Although this important finding is unlikely to impact routine management of HIV infection, it does suggest that reconstitution of a host immune system with a population of mutant cells is a possible avenue of research to explore.  Sexual transmission of HIV has been described from men to men, men to women, women to men, and women to women through vaginal, anal, and oral sex. The best way to avoid sexual transmission is abstinence from sex until it is certain that both partners in a monogamous relationship are not HIV infected. Because the HIV antibody test can take weeks to turn positive after infection occurs, both partners would need to test negative for at least 12 and up to 24 weeks after their last potential exposure to HIV. If abstinence is out of the question, the next best method is the use of latex barriers. This involves placing a condom on the penis as soon as an erection is achieved in order to avoid exposure to pre-ejaculatory and ejaculatory fluids that contain infectious HIV. For oral sex, condoms should be used for fellatio (oral contact with the penis) and latex barriers (dental dams) for cunnilingus (oral contact with the vaginal area). A dental dam is any piece of latex that prevents vaginal secretions from coming in direct contact with the mouth. Although such dams occasionally can be purchased, they are most often created by cutting a square piece of latex from a condom. Recent data has convincingly demonstrated that once a person has virologic suppression in blood after least six months of treatment, their likelihood of transmitting HIV to an uninfected partner, even without condoms, is virtually zero if they continue treatment. Two types of HIV have been characterized: HIV-1 and HIV-2. HIV-1 is the virus that was initially discovered and termed both LAV (Lymphadenopathy Associated Virus) and HTLV-III (Human T cell Lymphotropic Virus III). HIV-1 is more virulent and more infective than HIV-2, and is the cause of the majority of HIV infections globally. The lower infectivity of HIV-2 compared to HIV-1 implies that fewer of those exposed to HIV-2 will be infected per exposure. Due to its relatively poor capacity for transmission, HIV-2 is largely confined to West Africa. Stage III (also known as symptomatic HIV infection): By this stage, the immune system is significantly affected and the infected person now begins to manifest many symptoms, such as severe weight loss, chronic diarrhoea, persistant fever, tuberculosis, severe bacterial infections (e.g. pneumonia and meningitis). The replication of HIV can only take place inside human cells. The process typically begins when a virus particle bumps into a cell that carries a special protein called CD4 on its surface. The spikes on the surface of the virusparticle stick to the CD4 to allow the viral envelope to fuse with the cell membrane. HIV particle contents are then released into the cell, leaving the envelope behind. HIV destroys T cells called CD4 cells. These cells help your immune system fight infections. Healthy adults generally have a CD4 count of 800 to 1,000 per cubic millimeter. If you have HIV and your CD4 count falls below 200 per cubic millimeter, you will be diagnosed with AIDS. Michael Stuart Bronze, MD David Ross Boyd Professor and Chairman, Department of Medicine, Stewart G Wolf Endowed Chair in Internal Medicine, Department of Medicine, University of Oklahoma Health Science Center; Master of the American College of Physicians; Fellow, Infectious Diseases Society of America HIV strains in several compartments, such as the nervous system (brain and CSF) and genital tract (semen), can be genetically distinct from those in plasma, suggesting that they have been selected by or have adapted to these anatomic compartments. Thus, HIV levels and resistance patterns in these compartments may vary independently from those in plasma. Jump up ^ Tang J, Kaslow RA (2003). "The impact of host genetics on HIV infection and disease progression in the era of highly active antiretroviral therapy". AIDS. 17 (Suppl 4): S51–S60. doi:10.1097/00002030-200317004-00006. PMID 15080180. Finkel TH, Tudor-Williams G, Banda NK, et al. Apoptosis occurs predominantly in bystander cells and not in productively infected cells of HIV- and SIV-infected lymph nodes. Nat Med. 1995 Feb. 1(2):129-34. [Medline]. There are currently nine approved PIs that all have distinct toxicities. The most common side effects associated with these drugs are nausea and diarrhea, which occur more often with some PIs than others. For example, diarrhea is more common with NFV than other PIs but can occur with any and all drugs in this class. Many of the drugs in this class also increase blood lipid levels, some more than others with ATV and DRV appearing to have less effect on lipids other drugs in the class. Other unique toxicities associated with various PIs are kidney stones, kidney damage, and increases in blood bilirubin levels and potentially jaundice with IDV and ATV. Some of these drugs also have been associated with elevations in blood sugar levels and bleeding in hemophiliacs. Finally, little is known regarding the role these drugs may play in the development of lipodystrophy. There is also some data suggesting that LPV/RTV and DRV may be associated with an increased risk of cardiovascular events. Side effects vary and may include headache and dizziness. Serious side effects include swelling of the mouth and tongue and liver damage. Some people eventually develop drug-resistant strains of HIV. If you have serious side effects, your medications can be adjusted. Jump up ^ Klot, Jennifer; Monica Kathina Juma (2011). HIV/AIDS, Gender, Human Security and Violence in Southern Africa. Pretoria: Africa Institute of South Africa. p. 47. ISBN 0-7983-0253-4. Archived from the original on April 26, 2016. RNA testing (viral load test) detects HIV RNA in the blood. It is not commonly used for screening but can be helpful in detecting early HIV infection when a person is in the window period or if the screening tests are unclear. You can get HIV testing in most doctors' offices, public health clinics, hospitals, and Planned Parenthood clinics. You can also buy a home HIV test kit in a drugstore or by mail order. Make sure it's one that is approved by the Food and Drug Administration (FDA). If a home test is positive, see a doctor to have the result confirmed and to find out what to do next. Three groups of HIV-1 have been identified on the basis of differences in the envelope (env) region: M, N, and O. Group M is the most prevalent and is subdivided into eight subtypes (or clades), based on the whole genome, which are geographically distinct. The most prevalent are subtypes B (found mainly in North America and Europe), A and D (found mainly in Africa), and C (found mainly in Africa and Asia); these subtypes form branches in the phylogenetic tree representing the lineage of the M group of HIV-1. Co-infection with distinct subtypes gives rise to circulating recombinant forms (CRFs). In 2000, the last year in which an analysis of global subtype prevalence was made, 47.2% of infections worldwide were of subtype C, 26.7% were of subtype A/CRF02_AG, 12.3% were of subtype B, 5.3% were of subtype D, 3.2% were of CRF_AE, and the remaining 5.3% were composed of other subtypes and CRFs. Most HIV-1 research is focused on subtype B; few laboratories focus on the other subtypes. The existence of a fourth group, "P", has been hypothesised based on a virus isolated in 2009. The strain is apparently derived from gorilla SIV (SIVgor), first isolated from western lowland gorillas in 2006. With therapy, viral loads can often be suppressed to an undetectable level (< 20-75 copies/mL; optimal viral suppression); complete inhibition of viral replication appears impossible and may be unnecessary [redirect url='http://penetratearticles.info/bump' sec='7']