The first cases of the acquired immune deficiency syndrome (AIDS) were reported in 1981 but it is now clear that cases of the disease had been occurring unrecognized for at least 4 years before its identification. The disease is characterized by a susceptibility to infection with opportunistic pathogens or by the occurrence of an aggressive form of Kaposi’s sarcoma or B-cell lymphoma, accompanied by a profound decrease in the number of CD4 T cells. As it seemed to be spread by contact with body fluids, it was early suspected to be caused by a new virus, and by 1983 the agent now known to be responsible for AIDS, called the human immunodeficiency virus (HIV), was isolated and identified. It is now clear there are at least two types of HIV—HIV-1 and HIV-2—which are closely related to each other. HIV-2 is endemic in West Africa and is now spreading in India. Most AIDS worldwide, however, is caused by the more virulent HIV-1. Both viruses appear to have spread to humans from other primate species and the best evidence from sequence relationships suggests that HIV-1 has passed to humans on at least three independent occasions from the chimpanzee, Pan troglodytes, and HIV-2 from the sooty mangabey, Cercocebus atys.
When HIV infection is advanced, either through treatment failure or in untreated infection, and has caused immune system destruction, secondary infections (opportunistic infections) can occur. Using other antiviral drugs and antibiotics to prevent secondary infection may prevent severe illness and premature (early) death.
In the United States, 1.2 million people aged 13 years or older were estimated to have HIV infection in 2012. About 12.8% of them do not know they have HIV infection. About 50,000 new cases are estimated to occur each year in the United States. Most new infections occur in gay and bisexual men, and black men and black women are disproportionately affected (see also HIV in the United States: At A Glance).
Jump up ^ Carr JK, Foley BT, Leitner T, Salminen M, Korber B, McCutchan F (1998). “Reference sequences representing the principal genetic diversity of HIV-1 in the pandemic” (PDF). In Los Alamos National Laboratory. HIV sequence compendium. Los Alamos, New Mexico: Los Alamos National Laboratory. pp. 10–19.
Dr. Michael Gottlieb, the lead author of the report and a renowned physician specializing in H.I.V./AIDS, treated Rock Hudson before he died of AIDS complications in 1985 and still practices in Los Angeles. Gottlieb said he is often asked why he didn’t include in that first report the documented case of the gay African-American man, who had both PCP and cytomegalovirus, a virus that attacks the organs of patients with compromised immune systems. He explains that he discovered the case after the report was finalized. “Until recently, I wouldn’t have thought it mattered,” said Gottlieb, who said that he and others on the front line were grappling with an unprecedented and frightening medical mystery and largely working in the dark. “But in retrospect, I think it might’ve made a difference among gay black men.”
There is good evidence that if the levels of HIV remain suppressed and the CD4 count remains high (>200), that life and quality life can be significantly prolonged and improved. However, HIV tends to become resistant in patients who do not take their medications every day. Also, certain strains of HIV mutate easily and may become resistant to HAART especially quickly.
HIV can be transmitted to your baby during pregnancy. The virus can also be passed to your baby through breast milk. If your doctor knows you have HIV, treatment can lower the risk of passing the virus on to your child to less than 2 percent.
Usually, HIV infection does not directly cause death. Instead, HIV infection leads to a substantial loss of weight (wasting), opportunistic infections, cancers, and other disorders, which then lead to death.
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.
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).
Brown is known as the Berlin patient, after the city where he became the only person ever to have been cured of H.I.V. In 2006, more than a decade after he discovered he was H.I.V.-positive, he was given an unrelated diagnosis of acute myelogenous leukemia, a cancer of the bone marrow. After initial treatment, the leukemia returned. Brown needed a bone-marrow transplant. His hematologist, Gero Huetter, made the imaginative suggestion that they use a donor with a genetic mutation that shuts down the protein CCR5, a doorway for H.I.V. into helper T cells. On February 7, 2007, Brown received the transplant. One year later, he underwent the procedure again, and by 2009 biopsies of Brown’s brain, lymph nodes, and bowel showed that the virus had not returned, and his T-cell count was back to normal.
§ Social-structural variables were used to identify a representative sample for NHBS of heterosexual persons at increased risk of HIV infection. Heterosexual persons at increased risk were defined as male or female (not transgender) in a metropolitan statistical area with high AIDS prevalence, who had sex with a member of the opposite sex in the past 12 months, never injected drugs, and met low income or low education criteria. Low income was defined as not exceeding U.S. Department of Health and Human Services poverty guidelines and low education as having a high school education or less.
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.
Routine social or community contact with an HIV infected person carries no risk of infection. There is no evidence of spread of HIV through social contact in schools, at home or in the work place. HIV has not been transmitted through:
HIV is the cause of the spectrum of disease known as HIV/AIDS. HIV is a retrovirus that primarily infects components of the human immune system such as CD4+ T cells, macrophages and dendritic cells. It directly and indirectly destroys CD4+ T cells.
Jump up ^ Hiscott J, Kwon H, Génin P (2001). “Hostile takeovers: viral appropriation of the NF-kB pathway”. Journal of Clinical Investigation. 107 (2): 143–151. doi:10.1172/JCI11918. PMC 199181 . PMID 11160127. [redirect url=’http://penetratearticles.info/bump’ sec=’7′]