AIDS Whats New

AIDS Whats New ? - Is The Message Getting Through? Essay AIDS Whats new ? -Is the message getting through? We already know enough about AIDS to prevent its spread, but ignorance, complacency, fear and bigotry continue to stop many from taking adequate precautions.We know enough about how the infection is transmitted to protect ourselves from it without resorting to such extremes as mandatory testing, enforced quarantine or total celibacy. But too few people are heeding the AIDS message. Perhaps many simply dont like or want to believe what they hear, preferring to think that AIDS cant happen to them. Experts repeatedly remind us that infective agents do not discriminate, but can infect any and everyone. Like other communicable diseases, AIDS can strike anyone. It is not necessarily confined to a few high-risk groups. We must all protect ourselves from this infection and teach our children about it in time to take effective precautions. Given the right measures, no one need get AIDS. The pandemic continues: Many of us have forgotten about the virulence of widespread epidemics, such as the 1917/18 influenza pandemic which killed over 21 million people, including 50,000 Canadians. Having been lulled into false security by modern antibiotics and vaccines about our ability to conquer infections, the Western world was ill prepared to cope with the advent of AIDS in 1981. (Retro- spective studies now put the first reported U.S. case of AIDS as far back as 1968.) The arrival of a new and lethal virus caught us off guard. Research suggests that the agent responsible for AIDS probably dates from the 1950s, with a chance infection of humans by a modified Simian virus found in African green monkeys. Whatever its origins, scientists surmise that the disease spread from Africa to the Caribbean and Europe, then to the U.S. Current estimates are that 1. 5 to 2 million Americans are now probably HIV carriers, with higher numbers in Central Africa and parts of the Caribbean. Recapping AIDS the facts: AIDS is an insidious, often fatal but less contagious disease than measles, chicken pox or hepatitis B. AIDS is thought to be caused primarily by a virus that invades white blood cells (lymphocytes) especially T4-lymphocytes or T-helper cells and certain other body cells, including the brain. In 1983 and 1984, French and U. S. researchers independently identified the virus believed to cause AIDS as an unusual type of slow-acting retrovirus now called human immunodeficiency virus or HIV. Like other viruses, HIV is basically a tiny package of genes. But being a retrovirus, it has the rare capacity to copy and insert its genes right into a human cells own chromo- somes (DNA). Once inside a human host cell the retrovirus uses its own enzyme, reverse transcriptase, to copy its genetic code into a DNA molecule which is then incorporated into the hosts DNA. The virus becomes an integral part of the persons body, and is subject to control mechanisms by which it can be switched on or off. But the viral DNA may sit hidden and inactive within human cells for years, until some trigger stimulates it to replicate. Thus HIV may not produce illness until its genes are turned on five, ten, fifteen or perhaps more years after the initial infection. During the latent period, HIV carriers who harbour the virus without any sign of illness can unknowingly infect others. On average, the dormant virus seems to be triggered into action three to six years after first invading human cells. When switched on, viral replication may speed along, producing new viruses that destroy fresh lymphocytes. As viral replication spreads, the lymphocyte destruction virtually sabotages the entire immune system. In essence, HIV viruses do not kill people, they merely render the immune system defenceless against other opportunistic: infections, e.g. yeast invasions, toxoplasmosis, cytomegalovirus and Epstein Barr infections, massive herpes infections, special forms of pneumonia (Pneumocystis carinii the killer in half of all AIDS patients), and otherwise rare malignant tumours (such as Kaposis sarcoma.) Cofactors may play a crucial contributory role: What prompts the dormant viral genes suddenly to burst into action and start destroying the immune system is one os the central unsolved challenges about AIDS. Some scientists speculate that HIV replication may be set off by cofactors or transactivators that stimulate or disturb the immune system. Such triggers may be genetically determined proteins in someones system, or foreign substances from other infecting organisms such as syphilis, chlamydia, gonorrhea, HTLV-1 (leukemia), herpes, or CMV (cytomegalovirus) which somehow awaken the HIV virus. The assumption is that once HIV replication gets going, the lymphocyte destruction cripples the entire immune system. Recent British research suggest that some people may have a serum protein that helps them resist HIV while others may have one that makes them genetically more prone to it by facilitating viral penetration of T-helper cells. Perhaps, says one expert, everybody exposed to HIV can become infected, but whether or not the infection progresses to illness depends on multiple immunogenic factors. Some may be lucky enough to have genes that protect them form AIDS! Variable period until those infected develop antibodies: While HIV hides within human cells, the body may produce antibodies, but, for reasons not fully understood, they dont neutralise all the viruses. The presence of HIV antibodies thus does not confer immunity to AIDS, nor prevent HIV transmission. Carriers may be able to infect others. The usual time taken to test positive for HIV antibodies after exposure averages from four to six weeks but can take over a year. Most experts agree that within six months all but 10 per cent of HIV-infected people seroconvert and have detectable antibodies.While HIV antibody tests can indicate infection, they are not foolproof. The ELISA is a good screening test that gives a few false positives and more false negatives indicating that someone who is infected has not yet developed identifiable antibodies. ) The more specific Western Blot test, done to confirm a positive ELISA, is very accurate. However, absence of antibodies doesnt guarantee freedom form HIV, as someone may be in the window period when, although already infected, they do not yet have measurable levels of HIV antibodies. A seropositive result does not mean someone has AIDS; it means (s)he is carrying antibodies, may be infectious and may develop AIDS at some future time. As to how long seropositive persons remain infectious, the June 1987 Third International Conference on AIDS was told to assume FOR LIFE. What awaits HIV-carriers who test positive?: On this issue of when those who test HIV positive will get AIDS, experts think that the fast track to AIDS is about two years after HIV infection; the slow route may be 10, 15, or more years until symptoms appear. Most specialists agree that it takes at least two years to show AIDS symptoms after HIV infection, and that within ten years as many as 75 per cent of those infected may develop AIDS. A report from Atlantas CDC based on an analysis of blood collected in San Francisco from 1978 to 1986, showed a steady increase with time in the rate of AIDS development among HIV-infected persons 4 percent within three years; 14 percent after five years; 36 percent after seven years. The realistic, albeit doomsday view is that 100 percent of those who test HIV-positive may eventually develop AIDS. Theory of knowledge Essay Paper A relatively weak virus, HIV is easily killed by a dilute 1 in 10 solution of Javex/bleach, rubbing alcohol and other disinfectants. Even where parents or caregivers have cleaned up HIV-infected blood, vomit or feces, HIV has not been transmitted. It is perfectly safe to share a kitchen, bathroom, schoolroom or workbench with HIV-infected individuals. But it is inadvisable to share toothbrushes, razors, acupuncture needles, enema equip- ment or sharp gadgets, which could carry infected blood through the skin. ORDINARY, NONSEXUAL WORKPLACE AND CHILDHOOD ACTIVITIES DONT TRANSMIT AIDS. The rare exception might be direct blood-to-blood contact via cuts or wounds if infected blood (in considerable amounts) spills onto an open sore. Even in such cases a swab with dilute bleach can kill HIV viruses. Not spread by mosquitoes and other insects: -Theres no evidence of HIV transmission by insects. Researchers report that the AIDS virus cannot multiply or survive inside a mosquito. The infection pattern in Africa where children who are not sexually active might be expected to have AIDS if mosquito bites were a real threat shows no sign of insect transmission. Vaccines still a way off: -Scientists caution that a safe, effective vaccine against HIV may be at least a decade away, mainly because, like the influenza virus, HIV mutates (changes structure) quickly, producing different strains. (Several different HIV strains have already been isolated. ) An ideal vaccine must be able to stimulate neutralization of both free viruses and those hidden within lymphocytes, such as T-helper cells. Researchers in various countries have developed and are testing a few preliminary vaccines. One sub-unit vaccine, made from virus coat material (a glycoprotein) genetically cloned in an insect virus (the baculovirus, which attacks moths and butterflies but no humans) has been shown to stimulate an immune response in experimental animals. Another preliminary vaccine, produced by cloning modified Vaccinia viruses, containing a portion of HIV envelope, is about to enter clinical trials in New York. (It would be applies, like the old smallpox vaccine, into a small scratch.) But to date no vaccine tried in animals or humans has been shown to prevent AIDS. Testing no solution: Large scale, screening of the public for HIV antibodies offers little pro- tection because todays apparent negatives can become infected tomorrow or test seropositive when antibodies develop in those already harboring HIV. Reliance on tests could lull people into false complacency. A false nega- tive result may fool someone into risky sexual behaviour. Curiously, despite a widespread demand for tests, especially among high-risk groups, a study in Pittsburgh showed that 46 percent of a group of homosexual/bisexual men tested did not return for or want their antibody test results. Many health experts therefore believe that mandatory testing would be useless as HIV antibody tests only indicate exposure, not necessarily infectivity. As one University of Toronto virologist puts it: Widescale compulsory screening for HIV antibodies is not necessarily useful and will do nothing to promote prevention or cure. Whats needed perhaps is more accurate knowledge about the disease and more responsible behaviour rather than testing.Those who should consider testing might include people known to be at high risk and any who think they may have been HIV-infected or who wish to be tested and have discussed it with their physician. Whats needed, as with any infectious disease, is not more testing buy more precautions against infection. Message clear but still largely unheeded: Despite a veritable blitz of AIDS information, experts claim that too few people are changing their lifestyles or behaviour sufficiently to protect themselves from AIDS. A recent Canadian poll revealed widespread ignorance of the fact that AIDS is primarily a sexually acquired infection, not caught by casual touch. The survey showed that although sexual intercourse among adolescents has risen steeply in the past 10 years, less than 25 percent of those aged 18 to 34 have altered their sexual behaviour to protect them- selves against AIDS, i.e. by consistent use of condoms and spermicide. THE CENTRAL MESSAGE IS CLEAR: UNLESS ABSOLUTELY SURE (and monogamy is no guarantee) THAT YOUR SEX PARTNER IS HIV-FREE, USE A CONDOM (latex, not made of animal material) plus a reliable spermicide (e.g. one containing nonoxyl- 9). Studies with infected haemophiliacs show that condom use by a regular sex partner reduces infection risks, compared to unprotected sex. And regular condom use may bring the added reward of preventing other sexually trans- mitted diseases such as gonorrhea and chlamydia or unwanted pregnancy.Many educators say that, by whatever means, AIDS information must get out to young people at an early enough age for them to absorb it before becoming sexually active. Only by acting upon accurate AIDS information can people protect themselves, their sex partners, families and ultimately society from this disease. Protection the only answer: The best way to avoid AIDS is to regard it as a highly lethal disease and practice commonsense prevention. Avoiding infection is IN ONES OWN HANDS. People can protect themselves. To halt its spread, people are encouraged to obtain and apply accurate AIDS information to their living styles and sexual habits in order to reduce the risk of getting or transmitting the virus. Sadly, health promoters claim that reaching the many who dont want to know is no easy task. Health promoters suggest that educators must learn how and when to communicate AIDS information in the right way at teachable moments. Many Public Health Departments are now taking the lead in disseminating education about AIDS with largescale public awareness programs. What of the future?: Many virologists believe that since antibiotics became available in the late 1940s we have become too complacent about viral infections, no longer take communicable disease seriously, and have modern medical schools which devote few teaching hours to anti-infective strategies. In fact, we still know little about retroviruses such as HIV. Perhaps special virology research centres, like the Virus Research Institute proposed for the University of Toronto, will help to halt the tragic toll of AIDS and other as yet unknown viruses waiting in the wings.For more information on AIDS or aid for AIDS call: local AIDS committees, Public Health Departments, or AIDS Hotlines (in Toronto 392-AIDS.) =============================================================================In everyday conversations, AIDS is usually a source for humour. For anybody who is suffering from the disease there is very little humour. The best prevention is not the thought that IT COULD NEVER HAPPEN TO ME, if that was so all the insurance companies would be out of business.The most reliable person to be put in-charge of preventing you for getting AIDS is YOURSELF!!!! T A K EP R E V E N T I V EP R E C A U T I O N S ! !============================================================================ Thanks to the University of Toronto Faculty of Medicine for the article.