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HIV/AIDS was recognised as a novel illness in the early 1980s. An AIDS case is classified as "early" if the death occurred before 5 June 1981, when the AIDS epidemic was formally recognized by medical professionals in the United States. [1] [2]
All known subgroups of HIV-1 and HIV-2 are thought to have entered humans as distinct cross-species transmissions of Simian immunodeficiency virus (SIV) from primates. [3] [4]
SIV exists as distinct lineages that cluster in different species of primates. [3] HIV-1 is most similar to the SIV found in common chimpanzees (SIVcpz) in southeastern Cameroon, giving rise to the notion that HIV-1 emerged from chimpanzees in this area. [4] SIVcpz itself emerged in chimpanzees as the result of a recombination of two separate lineages of SIV known to infect red-capped mangabey, and Cercopithecus species. [3] [5]
HIV-1 group M (responsible for the global pandemic) is estimated to have emerged in humans around 1920 near Kinshasa, then part of the Belgian Congo. This estimation was the result of time-scaled evolutionary models being applied to modern samples and retrieved early samples of HIV-1 (M). [6] [7] It had previously been estimated from the genetic differences between LEO70 and DRC60 samples and later samples that HIV-1 group M had jumped into humans in 1908 ± 10 years. [8]
The earliest known sample of HIV-1 is from Kinshasa, Democratic Republic of the Congo (DRC) (formerly Zaire, formerly the Belgian Congo). The sample, designated LEO70, was isolated from the plasma of "an adult Bantu male" who also had a Sickle cell trait and G6PDD, in 1959. At the time of the samples isolation, he was living in Léopoldville, Belgian Congo. [9] The isolated strain was found to be most closely related to modern genome sequences of HIV-1 (M) subgroup D.
Possible cases of AIDS from this period include:
Researchers begin to note the spread of Pneumocystis pneumonia and concurrent Cytomegalovirus infections, considered novel to the European continent, and both AIDS related conditions. Some of these cases occurred in infants considered immunocompetent. [15]
In 1960, a woman in modern-day Kinshasa, Democratic Republic of the Congo (DRC) (formerly Zaire, formerly the Belgian Congo) died, and a lymph node sample was taken and fixed with Formaldehyde and preserved in paraffin. In 2008, the sample was tested by researchers, identifying partial HIV viral sequences. [8] The specimen, named DRC60 contained a strain of HIV-1 around 88% similar to LEO70, but was found to be most closely related to HIV-1 (M) subgroup A isolates. These two specimens are significant not only because they are the oldest known specimens of HIV-1, but because they show that the virus already had an extensive amount of genetic diversity by 1960. [8]
Robert Rayford, a 16-year-old boy who died in 1969, is considered to be the first recorded case of AIDS in the United States. [16] [17]
Researchers drew blood from 75 children in Uganda to serve as controls for a study of Burkitt lymphoma. In 1985, retroactive testing of the frozen blood serum indicated that 50 of the children had antibodies to a virus related to HIV. [18]
Arvid Darre Noe (an anagram of his birth name Arne Vidar Røed) was a Norwegian sailor and truck driver who was probably infected in Cameroon some time between 1962 and 1965, and died on 24 April 1976. His eight-year-old daughter had died three months earlier, and his wife died in December 1976. Tissues of Røed, his wife and daughter all tested positive for HIV-1 type O, in an epidemiology study in 1988. [19] [20]
Grethe Rask was a Danish surgeon who traveled to Zaire in 1964 then again in 1972 to aid the sick. She was likely directly exposed to blood from many Congolese patients, one of whom infected her. She became unwell in 1974, then returned to Denmark in 1977, with her colleagues baffled by her symptoms. She died of pneumocystis pneumonia in December 1977. Her tissues were examined and tested by her colleagues and found positive in 1987. [21] [22]
A Portuguese man was treated at the Hospital for Tropical Diseases in London by Professor Anthony Bryceson until he died of the disease in 1978. He is the first confirmed case of HIV-2 and it is believed he was exposed to the disease in Guinea-Bissau, where he lived between 1956 and 1966. [23]
Herbert Heinrich was a German concert violinist who died in 1979. Tests in 1989 found that he was HIV-positive, and there has been speculation that he was infected by a sex worker who was infected by Noe. [20]
The human immunodeficiency viruses (HIV) are two species of Lentivirus that infect humans. Over time, they cause acquired immunodeficiency syndrome (AIDS), a condition in which progressive failure of the immune system allows life-threatening opportunistic infections and cancers to thrive. Without treatment, the average survival time after infection with HIV is estimated to be 9 to 11 years, depending on the HIV subtype.
Various fringe theories have arisen to speculate about purported alternative origins for the human immunodeficiency virus (HIV) and the acquired immunodeficiency syndrome (AIDS), with claims ranging from it being due to accidental exposure to supposedly purposeful acts. Several inquiries and investigations have been carried out as a result, and each of these theories has consequently been determined to be based on unfounded and/or false information. HIV has been shown to have evolved from or be closely related to the simian immunodeficiency virus (SIV) in West Central Africa sometime in the early 20th century. HIV was discovered in the 1980s by the French scientist Luc Montagnier. Before the 1980s, HIV was an unknown deadly disease.
The spread of HIV/AIDS has affected millions of people worldwide; AIDS is considered a pandemic. The World Health Organization (WHO) estimated that in 2016 there were 36.7 million people worldwide living with HIV/AIDS, with 1.8 million new HIV infections per year and 1 million deaths due to AIDS. Misconceptions about HIV and AIDS arise from several different sources, from simple ignorance and misunderstandings about scientific knowledge regarding HIV infections and the cause of AIDS to misinformation propagated by individuals and groups with ideological stances that deny a causative relationship between HIV infection and the development of AIDS. Below is a list and explanations of some common misconceptions and their rebuttals.
Simian immunodeficiency virus (SIV) is a species of retrovirus that cause persistent infections in at least 45 species of non-human primates. Based on analysis of strains found in four species of monkeys from Bioko Island, which was isolated from the mainland by rising sea levels about 11,000 years ago, it has been concluded that SIV has been present in monkeys and apes for at least 32,000 years, and probably much longer.
The oral polio vaccine (OPV) AIDS hypothesis is a now-discredited hypothesis that the AIDS pandemic originated from live polio vaccines prepared in chimpanzee tissue cultures, accidentally contaminated with simian immunodeficiency virus and then administered to up to one million Africans between 1957 and 1960 in experimental mass vaccination campaigns.
This is a timeline of HIV/AIDS, including but not limited to cases before 1980.
AIDS-defining clinical conditions is the list of diseases published by the Centers for Disease Control and Prevention (CDC) that are associated with AIDS and used worldwide as a guideline for AIDS diagnosis. CDC exclusively uses the term AIDS-defining clinical conditions, but the other terms remain in common use.
AIDS is caused by a human immunodeficiency virus (HIV), which originated in non-human primates in Central and West Africa. While various sub-groups of the virus acquired human infectivity at different times, the present pandemic had its origins in the emergence of one specific strain – HIV-1 subgroup M – in Léopoldville in the Belgian Congo in the 1920s.
WHO Disease Staging System for HIV Infection and Disease in Adults and Adolescents was first produced in 1990 by the World Health Organization and updated in September 2005. It is an approach for use in resource limited settings and is widely used in Africa and Asia and has been a useful research tool in studies of progression to symptomatic HIV disease.
The human immunodeficiency virus (HIV) is a retrovirus that attacks the immune system. It can be managed with treatment. Without treatment it can lead to a spectrum of conditions including acquired immunodeficiency syndrome (AIDS).
Pneumocystis pneumonia (PCP), also known as Pneumocystis jirovecii pneumonia (PJP), is a form of pneumonia that is caused by the yeast-like fungus Pneumocystis jirovecii.
HIV superinfection is a condition in which a person with an established human immunodeficiency virus infection acquires a second strain of HIV, often of a different subtype. These can form a recombinant strain that co-exists with the strain from the initial infection, as well from reinfection with a new virus strain, and may cause more rapid disease progression or carry multiple resistances to certain HIV medications.
The discovery of disease-causing pathogens is an important activity in the field of medical science. Many viruses, bacteria, protozoa, fungi, helminths, and prions are identified as a confirmed or potential pathogen. In the United States, a Centers for Disease Control and Prevention program, begun in 1995, identified over a hundred patients with life-threatening illnesses that were considered to be of an infectious cause but that could not be linked to a known pathogen. The association of pathogens with disease can be a complex and controversial process, in some cases requiring decades or even centuries to achieve.
The subtypes of HIV include two main subtypes, known as HIV type 1 (HIV-1) and HIV type 2 (HIV-2). These subtypes have distinct genetic differences and are associated with different epidemiological patterns and clinical characteristics.
The Democratic Republic of the Congo was one of the first African countries to recognize HIV, registering cases of HIV among hospital patients as early as 1983.
HIV is commonly transmitted via unprotected sexual activity, blood transfusions, hypodermic needles, and from mother to child. Upon acquisition of the virus, the virus replicates inside and kills T helper cells, which are required for almost all adaptive immune responses. There is an initial period of influenza-like illness, and then a latent, asymptomatic phase. When the CD4 lymphocyte count falls below 200 cells/ml of blood, the HIV host has progressed to AIDS, a condition characterized by deficiency in cell-mediated immunity and the resulting increased susceptibility to opportunistic infections and certain forms of cancer.
The stages of HIV infection are acute infection, latency, and AIDS. Acute infection lasts for several weeks and may include symptoms such as fever, swollen lymph nodes, inflammation of the throat, rash, muscle pain, malaise, and mouth and esophageal sores. The latency stage involves few or no symptoms and can last anywhere from two weeks to twenty years or more, depending on the individual. AIDS, the final stage of HIV infection, is defined by low CD4+ T cell counts, various opportunistic infections, cancers, and other conditions.
A small proportion of humans show partial or apparently complete innate resistance to HIV, the virus that causes AIDS. The main mechanism is a mutation of the gene encoding CCR5, which acts as a co-receptor for HIV. It is estimated that the proportion of people with some form of resistance to HIV is under 10%.
Beatrice H. Hahn is an American virologist and biomedical researcher best known for work which established that HIV, the virus causing AIDS, began as a virus passed from apes to humans. She is a professor of Medicine and Microbiology in the Perelman School of Medicine at the University of Pennsylvania. In November 2002, Discover magazine listed Hahn as one of the 50 most important women scientists.
In parasitology and epidemiology, a host switch is an evolutionary change of the host specificity of a parasite or pathogen. For example, the human immunodeficiency virus used to infect and circulate in non-human primates in West-central Africa, but switched to humans in the early 20th century.