The description of aids its origin and spread in the human body
HIV-1 from chimpanzees and gorillas to humans[ edit ] Scientists generally accept that the known strains or groups of HIV-1 are most closely related to the simian immunodeficiency viruses SIVs endemic in wild ape populations of West Central African forests.
Upon infection and replication catalyzed by reverse transcriptase, recombination between the two genomes can occur.
Michael Worobey and colleagues observed that the growth of cities probably played a role in the epidemic emergence of HIV, since the phylogenetic dating of the two older strains of HIV-1 groups M and Osuggest that these viruses started to spread soon after the main Central African colonial cities were founded.
Fortunately, it almost never occurs until the immune system is almost completely destroyed, so it is not usually the first symptom.
What is aids
HIV itself can cause diarrhea if it infects the intestinal tract. A number of studies with subtype B-infected individuals have determined that between 40 and 50 percent of AIDS patients can harbour viruses of the SI and, it is presumed, the X4 phenotypes. Genetic analysis of this blood sample suggested that HIV-1 may have stemmed from a single virus in the late s or early s. Remain faithful in a relationship with an uninfected equally faithful partner with no other risk behaviour. As this happens, the reverse transcriptase, by jumping back and forth between the two different RNA templates, will generate a newly synthesized retroviral DNA sequence that is a recombinant between the two parental genomes. Still, by , AIDS was the fourth biggest cause of death in the world and the leading cause of death in Africa. These symptoms can last anywhere from a few days to several weeks. This cleavage is mediated by the packaged viral protease and can be inhibited by antiretroviral drugs of the protease inhibitor class. As a general guideline, if a cough does not resolve after several weeks, it should be checked by a medical practitioner. The classical process of infection of a cell by a virion can be called "cell-free spread" to distinguish it from a more recently recognized process called "cell-to-cell spread".
Increasingly, people living with HIV can remain well and productive for extended periods of time, even in low-income countries. The course of untreated HIV is not known but may go on for 10 years or longer in many people. Other misconceptions people may have include the following: "It can't happen to me.
Aids full form
Pulmonary TB requires ongoing treatment for at least 6 months, and close associates of the infected person must be tested for TB. Approximately 6 months after infection, the level of virions produced every day may reach a "set point. Fortunately, it almost never occurs until the immune system is almost completely destroyed, so it is not usually the first symptom. Regions in the LTR act as switches to control production of new viruses and can be triggered by proteins from either HIV or the host cell. The researchers believe that the virus crossed over from monkeys to humans when hunters became exposed to infected blood. The World Health Organization set a goal to bring treatment to 3 million people by It is known that drug-resistant viruses can be transmitted from one person to another. The treatment implications for a person infected with a drug-resistant virus are not yet known, but treatment will likely be difficult. Pain therapy at this stage invariably requires narcotics. The best viral load test result is "none detected," although this does not mean the virus is gone, only that it is not actively reproducing at a measurable level. Scientists also developed treatments to reduce mother to child transmission.
Many AIDS-defining conditions cause diarrhea, including parasitic, viral, and bacterial infections. After a person is infected with HIV, the body takes about 6 to 12 weeks and sometimes as long as 6 months to build up proteins to fight the virus.
Why did aids spread so quickly
For the lower GUD levels existing in the same city in the late s see above , they were much less likely. New drug therapy can keep this level called viral load low or undetectable, but this does not mean that other individuals cannot be infected. People may not have any symptoms or get sick during this time. The authors propose that these findings explain the temporal patterns of HIV emergence: no HIV emerging in tens of thousands of years of human slaughtering of apes and monkeys , several HIV groups emerging in the nascent, GUD-riddled, colonial cities, and no epidemically successful HIV group emerging in midth century, when GUD was more controlled, and cities were much bigger. The six remaining genes, tat, rev, nef, vif, vpr, and vpu or vpx in the case of HIV-2 , are regulatory genes for proteins that control the ability of HIV to infect cells, produce new copies of virus replicate , or cause disease. Male circumcision had little to moderate effect in their simulations, but, given the geographical correlation found, the authors propose that it could have had an indirect role, either by increasing genital ulcer disease itself it is known that syphilis , chancroid , and several other GUDs have higher incidences in uncircumcised men , or by permitting further spread of the HIV strain, after the first chains of sexual transmission permitted adaptation to the human organism. Early cases of HIV infection that were sexually transmitted often were related to the use of alcohol and other substances, and the majority of these cases occurred in urban, educated, white MSMs. Some molecular dating studies suggest that HIV-1 group M had its most recent common ancestor MRCA that is, started to spread in the human population in the early 20th century, probably between and While this number illustrates a formidable success in HIV treatment scale up, nearly half of all people in need are still waiting for treatment. These HIV-2 strains are probably dead-end infections , and each of them is most closely related to SIVsmm strains from sooty mangabeys living in the same country where the human infection was found. The theories centred on the role of parenteral risks, such as unsterile injections, transfusions ,     or smallpox vaccinations  are accepted as plausible by most scientists of the field. Hospice care is an appropriate choice for those who have run out of therapeutic options. This level becomes very high soon after a person is initially infected with HIV, then it drops. He was incorrectly called "Patient Zero" because at least 40 of the people known to be infected by HIV in had had sex with him, or with someone who had sexual intercourse with him. In that year, basketball player Magic Johnson announced he had HIV, helping to further bring awareness to the issue and dispel the stereotype of it being a gay disease.
HIV can be passed from a woman to a man during intercourse, but this is less likely because the skin of the penis is not as easily damaged.
They modelled people's 'sexual links', with different levels of sexual partner change among different categories of people prostitutes, single women with several partners a year, married women, and menaccording to data obtained from modern studies of sexual activity in African cities.
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