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  AIDS, World Issues

AIDS (acquired immunodeficiency syndrome), also abbreviated as HIV-AIDS  is a disease that affects people who have been infected with human immunodeficiency virus (HIV). It is said that someone has AIDS when your body due to the immunodeficiency caused by HIV, can not provide an adequate immune response against infection. Note the difference between being infected with HIV and with AIDS. A person infected with HIV is HIV positive and goes to develop a cadre of AIDS when their CD4 T cell level, cells that attack the virus, falls below 200 cells per milliliter of blood HIV is transmitted through these fluids body: blood, semen, vaginal secretions and breast milk.
AIDS is the inability of the immune system to fight infections and other pathological processes, and develops when the CD4 T lymphocyte level drops below 200 cells per milliliter of blood.
Normally, white blood cells and antibodies attack and destroy any foreign organism that enters the human body. This response is coordinated by a type of cells called CD4 lymphocytes. Unfortunately, HIV specifically targets cells that express the CD4 receptor, one of the most important are the CD4 + T cells and enter them. Once inside, the virus transforms its single-stranded genetic material (RNA) to a double-stranded (DNA) for incorporation into the host's own genetic material (infected person) and uses it to replicate or make copies of itself. When new copies of the virus out of blood cells to seek to attack other cells. Meanwhile, the cells from which they were killed. This cycle is repeated again and again.
To defend this production of virus, the immune system of a person produces many CD4 cells daily. Gradually the number of CD4 cells decreases, so that the person suffers from immunodeficiency, which means you can not fight viruses, bacteria, fungi and parasites that cause diseases, which leaves the person susceptible to diseases a healthy person would be able to face, such as atypical pneumonia and meningitis atypical. These diseases are mainly opportunistic infections. Since the body has mechanisms to control cell growth dependent on CD4 cells, the progressive destruction of these cells cause these mechanisms are not adequately regulated, resulting in consequence the presence of some neoplasms (cancer) that would not occur in people " healthy ". HIV also can infect brain cells, causing some neurological conditions.
Like other retroviruses, the virus's genetic information is in the form of RNA, which contains the "instructions" for the synthesis of structural proteins, which by binding under the new virus (virion), ie inherited characteristics, which are needed to replicate. Normally, in nature DNA or deoxyribonucleic acid is a source of genetic material from which to produce a single copy of RNA, but in the case of HIV, it does reverse the direction of the information, producing DNA from the simple RNA copy operation that is called reverse transcription, characteristic of retroviruses. The virus inserts its genetic information on the mechanism of cell reproduction (cell nucleus), thanks to the action of reverse transcriptase.

Clinical categories 

in the table below are covered the different stages of HIV infection.

• Category A: Patients with primary or asymptomatic infections.

• Category B: patients who have or have had symptoms that do not belong to the category C, but are associated with HIV infection:

• or bacillary angiomatosis.
• vulvovaginal candidiasis or or refractory oral candidiasis.
• or dysplasia of the uterine cervix or non-invasive cervical carcinoma.
• or pelvic inflammatory disease (PID).
• or fever less than 38.5 ° C or diarrhea, more than one month.
• or shingles (more than one episode or an episode with involvement of more than one dermatome.
• oral hairy leukoplakia or.
• or peripheral neuropathy.
• or idiopathic thrombocytopenic purpura (ITP).

•  Category C: patients who have or have presented some complications included in the definition of AIDS, 1987 WHO:

or opportunistic infections:

• Bacterial Infections:
• Recurrent Salmonella septicemia (different Salmonella typhi).
• Tuberculosis.
• Infection with Mycobacterium avium complex (MAI).
• Atypical Mycobacterial Infection.
• Viral infections:
• Cytomegalovirus infection (retinitis or disseminated).
• Infection with herpes simplex virus (HSV types 1 and 2) may be in the form of chronic bronchitis, pneumonitis or esophagitis.

• Fungal infections:
• aspergillosis.
• Candidiasis, disseminated both as the esophagus, trachea or lungs.
• coccidioidomycosis, extrapulmonary or disseminated.
• extrapulmonary Cryptococcosis.
• Histoplasmosis, disseminated or extrapulmonary either.
• protozoal infections:
• Pneumocystis jiroveci pneumonia.
• Toxoplasmosis neurological
• chronic intestinal cryptosporidiosis.
• Isosporiasis bowel disease.

•  Processes chronified bronchitis and pneumonia.
•  Processes associated directly with HIV:
• HIV-related dementia (HIV encephalopathy).
• or progressive multifocal leukoencephalopathy.
• or wear or wasting syndrome syndrome.
• Processes tumor:
• Kaposi's sarcoma.
• Burkitt lymphoma.
• Other non-Hogdkin lymphomas, particularly immunoblastic lymphoma, primary brain lymphoma or B-cell lymphoma
• or invasive cervical carcinoma.

HIV multiplies, after the primary acute phase of infection in the lymphoid organs, overwhelmed with an effort that ends up causing a severe reduction in the production of lymphocytes. The weakening of the defense opens the door to opportunistic infections by bacteria, fungi, protists and viruses. In many cases the organisms responsible are present before, but develop a disease only when they cease to be contained by cellular immune mechanisms that HIV destroys. None of these diseases assaults only to HIV-positive, but some were almost unknown before the HIV epidemic and in many cases who are accompanying or variants define AIDS are different in their development or epidemiology.

History

The AIDS era officially began June 5, 1981, when the CDC (Centers for Disease Control and Prevention (Centers for Disease Control and Prevention) U.S. convened a press conference where he described five cases of Pneumocystis carinii pneumonia in Los Angeles next month were found several cases of Kaposi sarcoma, a type of skin cancer. The first findings of these cases were performed by Dr. Michael Gottlieb of San Francisco.
Although doctors knew both Pneumocystis carinii pneumonia and Kaposi's sarcoma, the joint appearance of both in several patients got their attention. Most of these patients were sexually active gay men, many of whom also suffered from other chronic diseases that were later identified as opportunistic infections. Blood tests that they did to these patients showed that they lacked the proper number of a type of blood cell called CD4 + T. Most of these patients died within months.
By the appearance of pinkish spots on the body of the infected, the press began to call AIDS, the "pink plague", causing confusion, attributing it to homosexuals, but soon also noted that Haitian immigrants suffering United States, injection drug users and recipients of blood transfusions, which led to talk of a club of the four axes that incorporated all these groups considered at risk of acquiring the disease. In 1982, the new disease was officially named the name of Acquired Immune Deficiency Syndrome (AIDS), which replaced other name proposed as Gay-related immune deficiency (GRID).
Until 1984, held various theories about the possible cause of AIDS. More support the theory that AIDS posed a disease basically epidemiology. In 1983 a group of nine gay men with AIDS in Los Angeles, who had sexual partners in common, including another man in New York who had sex with three of them served as a basis to establish a pattern of contagion typical of infectious diseases.
Other theories suggest that AIDS arose because of excessive drug use and high sexual activity with multiple partners. Also suggested that the inoculation of semen in the rectum during anal sex practice, combined with the use of nitrite inhalants called poppers, produced immune system suppression. Few scholars take seriously these theories, although some people still promote them and deny that AIDS is the result of HIV infection.
The currently recognized theory, argues that HIV comes from a virus called "simian immunodeficiency virus" (SIV, in English), which is identical to HIV and AIDS cause similar symptoms in other primates.

At that time AIDS victims were isolated by the community, friends and even family. Children who had AIDS were not accepted by schools because of protests from parents of other children, this was the case of American teenager Ryan White. People were afraid to approach the infected and who thought that HIV could be spread by casual contact such as shaking hands, hugging, kissing or sharing utensils with an infected.
At first the gay community was blamed for the emergence and subsequent spread of AIDS in the West. Even some religious groups came to say that AIDS was God's punishment for homosexuals (this belief is still popular among certain minority Christian and Muslim believers). Others point out that the lifestyle "depraved" of homosexuals was responsible for the disease. Although AIDS was initially spread faster through gay communities, and most of those with the disease in the West were gay, this was due, in part because in those days was not common to use gay condom because it is considered that this was only a contraceptive method. On the other hand, the diffusion in Africa was mainly through heterosexual

Current knowledge of the disease

HIV is related to other viruses that cause AIDS-like disease. It is believed that this virus was transferred from animals to humans in the early twentieth century. There are two different viruses that cause AIDS in humans, HIV-1 and HIV-2. The first reservoir species are chimpanzees, whose virus itself, the SIVcpz, is derived. HIV-2 derived from the SIVsm, typical of a species of monkey in West Africa. In both cases the interspecies transmission has occurred several times, but the current pandemic resulted from the extension of the group M HIV-1, according to estimates from an infection in Central Africa, where the virus expresses the maximum diversity in the first half of the twentieth century.
The current pandemic began in Central Africa, but went unnoticed until it began to affect people in rich countries, where AIDS immunosuppression could not be easily confused with impoverishment due to other causes, especially for medical systems and disease control very well resourced. The earliest human sample known to contain HIV was taken in 1959 to a British sailor who apparently contracted it in what is now the Democratic Republic of Congo. Other samples containing the virus were found in an American man who died in 1969 and in 1976 a Norwegian sailor. It is believed that the virus is spread through sexual activity, possibly through prostitutes in urban areas of Africa. As the first infected traveled the world, were carrying the disease to several cities on different continents.
Currently, the most common way that HIV is transmitted is through unprotected sexual activity and needle sharing among injecting drug users. The virus can be transmitted from a pregnant mother to her child (vertical transmission). In the past also spread AIDS through blood transfusions and the use of derived products for the treatment of hemophilia or sharing of unsterilized medical equipment, but now this happens very rarely, except the ultimate in poor regions, because the checks on these products.
Not all patients infected with HIV have AIDS. The criteria for diagnosing AIDS can vary from region to region, but the diagnosis typically requires:
• An absolute count of CD4 T cells below 200 per cubic millimeter or
• The presence of any of the typical opportunistic infections, caused by agents unable to produce disease in healthy people.
A person infected with HIV is called "HIV positive" or "HIV positive" (HIV +) and uninfected are called "seronegative" or "HIV negative" (HIV-). Most people with HIV do not know they are.
Primary HIV infection is called "seroconversion" and may be accompanied by a series of nonspecific symptoms like the flu, for example, fever, muscle and joint aches, sore throat and swollen lymph nodes. At this stage the transmitter is infected at any other stage of the disease, since the amount of virus in your body is higher than achieved. This is because not yet fully developed host immune response. Not all newly infected with HIV suffer from these symptoms and they all eventually become asymptomatic individuals.
During the asymptomatic stage, each day there are thousands of millions of HIV virus, which is accompanied by a decrease in CD4 + T cells. The virus is not only found in the blood, but throughout the body, particularly in the lymph nodes, brain and genital secretions.
The time taken for the diagnosis of AIDS since the initial infection of HIV is variable. Some patients develop any symptoms of immunosuppression a few months after being infected, while others remain asymptomatic for 20 years.
The reason why some patients do not develop the disease and why there is so much variability in the interpersonal spread of the disease is still under study. The average time between initial infection and the development of AIDS ranges from eight to ten years without treatment.

Women and AIDS

According to the United Nations Fund for Women (UNIFEM), although HIV infection began focusing primarily on men, today women account for 50% of people infected with HIV. Even in regions like sub-Saharan Africa, women represent 60% of the total HIV population.

Prevention

The only cause of transmission is the exchange of body fluids, particularly blood and genital secretions. The HIV virus cannot be transmitted by the breath, saliva, casual contact by touching, shaking hands, hugging, kissing on the cheek, mutual masturbation with another person or sharing eating utensils such as glasses, cups or spoons. Instead it is theoretically possible that the virus is transmitted from person to person through kissing mouth to mouth, if both people have bleeding wounds or gums sore, but that case has not been documented and it is considered very unlikely, because saliva contains concentrations much lower than such as semen, saliva and also because it has antiviral properties that make HIV destroys.

Penetration: HIV infection through sex has been proven from man to woman, woman to man, woman to woman and man to man. The use of latex condoms is recommended for all types of sexual activities including penetration. It is important to emphasize that they should use condoms made of latex material, for another condom (ram) that exists in the market, made from organic material, is not effective for prevention. Condoms are an estimated 90-95% effective in preventing pregnancy or the spread of disease, and used properly, that is, well preserved, open it carefully and properly placed, is the best means of protection against transmission of HIV. It has been shown repeatedly that HIV can not effectively pass through intact latex condoms.

Anal sex: because of the sensitivity of the tissues of the anus and the ease with which it is sore, is considered the most risky sexual activity. That's why condoms are also recommended for anal sex. The condom should be used only once, throwing it away and use another condom every time. Due to the risk of tearing (both the condom as the skin and the lining of the vaginal walls and anal) recommends the use of water-based lubricants. Vaseline and oil-based lubricants or oil should not be used with latex condoms because they weaken and become prone to tear.

Treatment

There are now drugs called antiretrovirals that inhibit essential enzymes, reverse transcriptase, reverse transcriptase or protease, thereby reducing HIV replication. In this way slows the progression of disease and opportunistic infections, so even if AIDS can not properly cured, it can develop with continued use of these drugs in chronic illness compatible with a long and almost normal. The HIV enzyme, reverse transcriptase, an enzyme that converts RNA to DNA, which has become one of the main targets in antiretroviral treatment.
In 2007 the European Medicines Agency (EMEA for its acronym in English) authorizes the drug Atripla that combines three of the most common antiretrovirals in one tablet. The active substances are efavirenz, emtricitabine and tenofovir disoproxil. The drug is indicated for the treatment of virus-1 in adults.
The common denominator of the treatments currently applied is the combination of drugs antiretrovilares, commonly called "cocktail". These "cocktails" have replaced traditional therapies that only one drug remain in the case of pregnant women with HIV. Different drugs tend to inhibit virus replication and slow down the deterioration of the immune system. The "cocktail" drug consists of two reverse transcriptase inhibitors (drugs) AZT, DDI, DDC, 3TC and D4T) and an inhibitor of other enzymes proteases.
By inhibiting different enzymes, drugs involved in different stages of virus multiplication process, preventing this process comes to an end. The advantage of the combination lies precisely in not attacking the virus in one place, but give "simultaneous and different strokes." The reverse transcriptase inhibitors introduce a wrong genetic information "or" incomplete "which makes the multiplication of the virus and determined his death. The protease inhibitors act by preventing infected cells and the" assembly "of proteins necessary for formation of new viral particles.
In 2010, the elimination of the virus found in a leukemia patient receiving a bone marrow transplant from a donor with a rare genetic mutation that makes him immune to HIV infection, recovered from both diseases. Being a very rare mutation and a high risk operation, the possibility that this becomes a practical solution is almost nonexistent at the moment. Despite the findings, such operations require doses of immunosuppressants for life. The genetic defect in question makes T cells do not express CCR5 or CXCR4 receptor that the virus needs to enter recognize the cell.

The protein SEVI

According to a study prepared in 2007 by scientists from the Universities of Ulm and Hannover, in conjunction with Spanish scientists, has discovered a protein in human semen, which facilitates the transmission of virusVIH.
Often the amount of virus in the semen does not reach the minimum levels expected to be generated contagion. However, this protein called SEVI, plays a role of facilitator for the spread of infection, with concentrations of HIV in semen that otherwise would never have produced infection.
This protein is expressed in two different formats or architectures. SEVI is the amyloid structure, which has the capacity to mutate to become pathogenic or biological properties. This protein significantly promotes the spread by semen, facilitating the distribution of virus infection.
SEVI concentrating the virus acts on the cell surface, which will then enter massively into the cytoplasm.

Theories dissidents

There is a minority group of scientists and activists emerged in the 80's questioning the link between HIV and AIDS, and even the very existence of the virus. They also put into question the validity of current testing methods. These dissenters argue that they are invited to conferences on the disease and who receive no monetary support for their research.

Significant members of this movement are Professor of Molecular and Cellular Biology Peter Duesberg, the mathematician Serge Lang, medical physics Eleni Papadopulos-Eleopulos, Harvey Bialy molecular biologist, chemist expert on protease inhibitors and David Rasnick Kary Nobel Prizes Mullis (Chemistry 1993) and Walter Gilbert (Chemistry 1980).

Some of these dissident scientists accuse the orthodox AIDS scientists of scientific incompetence and deliberate fraud. According to these dissidents, officially accepted treatments would cause AIDS, considering that this assertion is supported by the pharmacokinetics of drugs, and can be checked with a careful reading of the prospectus.

Position with greater consensus in the scientific community

Within the scientific community there is broad consensus on HIV / AIDS. And although there are still several aspects of the disease are unknown, it is considered that the information that establishes the causal relationship between HIV and AIDS is overwhelming.