In one of the most promising developments in more than 20 years, scientists claim that drugs used to control HIV/AIDS in patients may also be effective in preventing the disease in the first place.
The drugs in question are tenofovir (Viread) and emtricitabine, or FTC (Emtriva), sold in combination as Truvada by Gilead Sciences Inc. Gilead is the California company best known for inventing Tamiflu.
Previous research has been aimed at finding a vaccine against HIV/AIDS, with the intention of conditioning the immune system against the disease. But these drugs work differently. They simply keep the virus from reproducing, and have already been used successfuly by health care workers to prevent them from being infected by the virus carried by patients.
This approach to fighting HIV/AIDS has been tempting researchers for many years, but has only recently become feasible as preventative drugs have been developed that are safe for non-infected persons to take. Previous drugs had unreasonable effects for uninfected persons.
That situation changed when Tenofovir came on the market in 2001. Tenofovir is powerful and safe, and it only has to be taken once a day. It also does not interact with other medicines or birth control pills, and manifests less drug resistance than other AIDS medications.
Monkey studies show exciting results
A major study by the CDC (Centers for Disease Control and Prevention) in Atlanta, Georgia involved six macaques. The monkeys were given a combination of Tenofovir and FTC and then administered a deadly combination of monkey and human AIDS viruses. They were given the viruses in rectal doses to simulate contact between gay men.
Each was given 14 weekly exposures of the virus, and none of the monkeys became infected. In a control group which did not receive the drugs, all but one got the disease, normally after just two exposures.
The scientists then stopped giving the drugs to the test group to see if the prevention was only temporary. The results were equally impressive. None of the monkeys contracted the disease. "We're now four months following the animals with no drug, no virus. They're uninfected and healthy," reported a CDC researcher.
Now other research teams are pushing to have this drug combination tested on humans. A $29 million CDC study of drug users in Botswana will now be switched to this new drug combination.
Another study of 400 heterosexual women in Ghana by the Family Health Initiative, and funded by the Bill and Melinda Gates Foundation, is studying the effects of tenofovir alone.
But several other studies have failed to materialize because studies of this nature immediately raise suspicions that scientists are using local people as guinea pigs. The fear is that they will intentionally expose the test subjects to the virus.
The cost of tenofovir and Truvada also make testing difficult. In African countries condoms are now liberally donated by companies, aid groups, UN agencies, and western governments. While the drugs are relatively cheap, the cost remains an impediment.
Nevertheless researchers have been reinvigorated by the stunning results out of Atlanta, and new tests are going ahead in pockets of interest around the world.
Showing posts with label Aids HIV. Show all posts
Showing posts with label Aids HIV. Show all posts
AIDS, The Fear Epidemic
By any measure, AIDS is a frightening disease. It is physically devastating, incurable, and lethal. And it is spreading at a menacing pace. Fear and misconceptions about AIDS, however, have spread faster than the disease itself.
Federal health officials stress that the AIDS virus has spread almost exclusively by three routes: by sexual intercourse, through blood contact (contamination with or transfusion of infected blood or blood products), and from an infected pregnant woman to her fetus or newborn. The only other known instances in which the virus was transmitted, say officials, involved artificial insemination or organ transplants from infected donors.
But many people remain unconvinced. They fear that casual personal contact with an AIDS victim—a handshake, a sneeze, a drink from the same glass might lead to infection. A child with AIDS attempting to attend school can throw a community into a frenzy. An AIDS patient returning to work may find coworkers deserting the job in protest.
In short, anxiety about AIDS has itself become epidemic. Part of the problem is that AIDS is a new disease mysterious in its origin and initially baffling in its symptoms and cause. But the impression that scientists are groping amid a welter of unresolved questions is misleading. A vast amount of critical knowledge has already been gained about AIDS, and more is being learned all the time.
The epidemic first surfaced in the late 1970s, when rare cancers and uncommon infections began appearing in a number of gay (homosexual) men. Those illnesses were linked with a severe deficiency in the body's immune-defense system—a disorder initially called GRID, for Gay-Related Immune Deficiency. As late as mid-1981, gay men were still the only known victims in the United States, creating the impression that AIDS arose from something exclusive to that group.
By 1982, when the name became AIDS, for "acquired immune deficiency syndrome," the first currents of fear jolted the health-care community. The number of AIDS cases was rising geometrically, and the disease had appeared in two more groups—intravenous drug users and hemophiliacs. Not only did the pattern imply an infectious agent, but the disease was now affecting three of the principal groups vulnerable to hepatitis B infection—a viral illness that's also an occupational hazard among health workers.
AIDS would subsequently prove to be much less contagious than hepatitis B, partly because the number of hepatitis B virus particles in blood is up to a billion times greater than the number of AIDS virus particles. But no one knew that in 1982. Nor was it known that the AIDS virus doesn't penetrate intact skin or the linings of the respiratory and digestive tracts—and thus could not be transmitted by such things as a kiss on the lips, a cough, or food prepared by a person with AIDS.
With the number of cases doubling every six months, medical personnel on the front line became increasingly fearful for their own safety. That fear soon became evident to the public at large, helping to confirm impressions that a virulent plague was loose in the land. As public fear of the threat grew, scientific understanding of the disease advanced rapidly.
By mid-1984, three independent research teams in the United States and France had conclusively identified the virus that causes AIDS. Discovery of the virus—now designated "human immunodeficiency virus," or HIV—immediately opened new avenues of research into every aspect of the disease. Investigators have already deciphered the genetic code of the virus in search of ways to attack it. Others probing for clues to therapy have explored its crippling effect on the immune system.
For epidemiologists, who investigate the incidence, transmission, and patterns of disease, identification of the virus was the indispensable handle for a powerful new tool. It meant that a test could now be developed to detect individual exposure to the virus, information vital for deeper insight into the epidemic and its spread.
Elisa: Testing for Exposure to Aids
By 1985, a simple, inexpensive blood test for detecting exposure to the AIDS virus had been developed and approved for use. Called ELISA (for enzyme-linked immunosorbent assay), the test detects antibodies produced by white blood cells in response to the presence of the virus. Developed primarily to screen potential blood donors, ELISA has also served as a versatile research tool, greatly facilitating analysis of the epidemic's path.
Before ELISA, it was difficult to trace the spread of the virus. There was no practical way to detect it in people without symptoms, who represent the largest number of those infected. By mid-1988, about 65,000 cases of AIDS had been reported to the U.S. Centers for Disease Control (CDC). An estimated 325,000 people had AIDS-related complex (ARC), a term used to describe a condition that includes (in addition to laboratory evidence of immunodeficiency) swollen glands, recurrent fever, weight loss, or a combination of those symptoms. When persons with ARC develop any one of a number of opportunistic infections (or Kaposi's sarcoma), they are considered to have developed AIDS.
An estimated 1.6 million to 3.2 million additional people may be infected with the virus but have no symptoms of illness. Although their blood reveals antibodies to the virus—as determined by two consistently positive ELISA tests and a more sophisticated (and costly) confirming test called Western blot analysis—they may have no other laboratory or clinical signs of disease. Most public-health officials estimate that 30 to 50 percent of those people will ultimately develop full-blown AIDS.
With a practical means of detection in hand, researchers began probing areas previously obscure. For example, how fast was the virus spreading to the general population—or among intravenous-drug users, or gay men? Was it infecting family members who had no sexual contact with a victim in the home? Were some sexual practices riskier than others? Since 1985, a wealth of new information has become available to address those questions and others.
Some of the findings are uncompromisingly bleak. Among high-risk groups, the AIDS virus is cutting a widening swath of infection, particularly in areas that have already borne the brunt of the epidemic, such as metropolitan New York and San Francisco. The infection is also spreading among young adults in inner-city minority groups, especially black and Hispanic intravenous-drug users and their sexual partners. One analysis of blood tests administered to some 300,000 military recruits found the rate of infection in blacks to be four times that in whites.
Federal health officials have predicted that the cumulative total of AIDS cases could reach 270,000 by 1991, with 179,000 deaths. Most of those will be people who are already infected with the virus, the officials said.
The grim projections of unfolding tragedy have overshadowed all other emerging information about the epidemic. But there has been another side to the news. An increasing number of epidemiological studies now point to an unmistakable conclusion: The reassurances from health officials about casual contact with AIDS patients are well founded. As CDC director James O. Mason, M.D., put it, "This is a very difficult disease to catch."
Transmission appears to require not only direct insertion of the virus into the bloodstream but also a substantial dose of the virus much more than could be transmitted by casual contact. Indeed, a consistent pattern in people who become infected is frequent or severe exposure to the virus.
Even in sexual intercourse—the primary route of infection—the virus does not appear to spread easily. Like most sexually transmitted diseases, AIDS is strongly associated with a highly active sex life and multiple partners.
Homosexual Transmission
Among gay and bisexual men, the disease first appeared in those with extremely large numbers of sexual partners a lifetime average of over 1000 partners, according to one early epidemiologic study. It's not known whether multiple sexual contacts raise the risk simply by raising the odds that a person will encounter the AIDS virus once, or by some process in which the body's defenses are worn down (perhaps through exposure to other sexually transmitted diseases), or both. All that's known for sure is that having a large number of sexual partners raises the risk.
Now that the virus is more prevalent—and the odds of catching it (among people at risk) are higher—the average number of sexual partners reported by people who contract the disease would be far less than 1000. No precise numbers, however, are available.
A key factor in the rapid spread of the virus among gay and bisexual men is the practice of anal intercourse, probably because the surface membranes and blood vessels of the anal canal are vulnerable to small fissures or tears during intercourse. Such tears may allow virus carried in semen to gain entry into the bloodstream of the receiving partner. The risk of viral transmission is especially high for the partner accepting penetration (receptive anal intercourse). In one six-month study examining transmission of the virus in gay men, a University of Pittsburgh research team found receptive anal intercourse to be the major risk factor in infection. At the outset, none of the men showed any evidence of AIDS virus in their blood. After six months, however, antibodies to the virus were found in a number of the subjects, especially among men who had had two or more sexual partners. In that group, men engaging in receptive anal intercourse had 16 times the infection rate as those having no anal intercourse.
As yet, there's no scientific evidence that sexual practices other than anal-related sex lead to AIDS-virus transmission in gay men. However, only a few large studies have compared the effects of different sexual practices.
One such study was conducted by University of California researchers over a two-year period for the San Francisco Men's Health Study. The California investigators examined infection rates among some 800 gay or bisexual men with different sexual histories. No difference in infection rates was found between those who engaged solely in oral-genital sex and those who had no sexual partners at all.
The California researchers concluded that the risk of AIDS-virus transmission by oral-genital contact was minimal. But they cautioned—as did the Pittsburgh group—that their findings did not prove that sexual activity other than anal intercourse posed no risk among gay men. They pointed out that their results were based on a relatively small number of observations and could not completely exclude the possibility of transmission by oral-genital sex.
Indeed, caution has been the watchword among public-health officials offering preventive advice. Since more than 90 percent of AIDS cases have occurred in gay or bisexual men and intravenous-drug users, the message to those high-risk groups has stressed avoiding any possible risk. One drawback of that approach, however, is that it makes AIDS appear easier to catch than it actually is. Some public-health workers, for example, warn against deep kissing involving exchange of saliva. But there's no evidence that the virus is transmitted that way.
Heterosexual Transmission
In contrast to oral sex or deep kissing, vaginal intercourse is clearly an important route of infection. The AIDS virus can be spread by either a man or a woman during intercourse.
On a relative scale, vaginal intercourse appears to be less effective in spreading the virus than anal intercourse, and less contagious from female to male than the reverse. As yet, the risk of transmission in a single act of vaginal intercourse is unknown. But current evidence suggests that frequent or long-term sexual exposure with an infected partner or partners is an important factor in transmission.
As of mid-1988, about 4 percent of newly diagnosed AIDS cases in the U.S. can be traced to heterosexual transmission. A large number of the victims are spouses or long-term sexual partners of AIDS patients or other high-risk individuals, particularly intravenous-drug users. Another large segment includes immigrants from Haiti and central Africa, where the virus spreads mainly by heterosexual intercourse.
Some confusion initially surrounded the status of Haitians, who were once listed as a separate risk group for AIDS. Epidemiologists have since found that the infection rate is not high among Haitians who are longterm U.S. residents. It's high, though, among recent immigrants with a history of venereal disease or sexual contact with prostitutes. In both Haiti and central Africa, infected prostitutes are an important factor in the spread of the virus among heterosexuals.
Reports from central Africa also show that AIDS is concentrated among urban people who are very sexually active. The average AIDS patient had more than 30 sex partners a year, including frequent contacts with prostitutes.
Overall, heterosexual spread of the infection often involves multiple sexual exposures to the virus. Even under these circumstances, however, infection is far from automatic. In a number of studies based on antibody tests, 50 to 65 percent of the regular heterosexual partners of patients with AIDS or advanced AIDS-related illness have shown no evidence of the virus in their blood. And among the wives or regular sex partners of hemophiliacs with AIDS, 90 to 95 percent were not infected.
The fact that such prolonged sexual exposure often fails to cause infection certainly argues against fears that a bathtub, toilet seat, or the air around an AIDS patient could pose a threat.
Public-health officials generally recommend using condoms during anal or vaginal intercourse and oral-genital sex to reduce the risk of AIDS-virus transmission. CDC investigators, after evaluating many studies from around the world, concluded that barrier contraceptives—condoms, spermicides, and diaphragms used with spermicides—are effective in reducing the risk of sexually transmitted diseases, including AIDS. Lubricants, if used, should be water-based; petroleum products can damage latex.
One lab experiment demonstrated that the AIDS virus can't penetrate an intact latex condom. Another showed that a common spermicide, nonoxynol-9, inactivates the virus and kills the white blood cells that carry it. (Nonoxynol-9 is the spermicide in many contraceptive jellies and foams, and the active ingredient in the contraceptive sponge Today.)
Blood-to-Blood Contact
The rapid spread of the AIDS virus among intravenous-drug users fosters the impression that the virus is highly infectious. Actually, some common practices among addicts who use needles are what make them especially vulnerable. And while there is some evidence that gay people have modified their risk behavior, drug abusers have not.
In addition to the frequency of injections—at least daily in many users—intravenous-drug addicts often share their needles and syringes. Indiscriminate sharing of injection paraphernalia has become common at drug "shooting galleries," where addicts go to rent or share equipment. "Often, the same needle will be used for up to 50 injections until it is no longer usable," reports Peter Selwyn, M.D., medical director of a drug-treatment program for addicts at Montefiore Medical Center in the Bronx, New York.
The risk of contamination is multiplied by another practice—drawing blood back into the syringe so that any remaining drug can be flushed out of the syringe and into the vein. If an addict is infected with the virus, a significant dose of it may be transmitted to the next sharer. In short, intravenous-drug use is an extremely effective way of acquiring a blood-borne disease—even one as difficult to contract as AIDS.
Some people have proposed that government agencies should make sterile needles and syringes available to intravenous-drug users, either free or at cost. Facing the threat of an AIDS epidemic in 1984, the Amsterdam (Netherlands) Municipal Health Service adopted such a plan. It appears to be working. The number of addicts using intravenous drugs has not increased, and more addicts than ever have been motivated to enter treatment for their addiction. Similar programs have since been initiated in Sweden, Great Britain, France, Italy, and Australia.
Such proposals in the United States have generally met with strong opposition. In 1988, the first attempt at a free-needle program was made in Portland, Oregon; it stalled when insurance coverage was refused. New York City began a similar program the same year. Yet even advocates of the idea recognize it as a stopgap measure. They emphasize the need for more drug-treatment centers and a multifaceted approach to the problem. But an epidemic often demands swift action. Cheap, clean needles and syringes would at least reach the inner-city battleground where AIDS has hit hardest and where the real war on drugs is being fought—and lost.
The experience of health-care workers, meanwhile, provides a striking contrast to the epidemic among intravenous-drug users. Seven separate studies in the United States and England have examined the outcome of needle-stick and other exposures among health workers caring for AIDS patients. Approximately 1500 people—nurses, physicians, medical students, technicians, and laboratory workers—were studied to determine whether their exposures had resulted in infection. Most of the exposures were needle-stick injuries from instruments that had just been used for an AIDS patient. The rest were direct exposures of a mucous membrane, such as a splash of infected blood into the eye or nostrils.
Despite the large number of exposures, only five of the 1500 workers developed AIDS-virus antibodies in their blood. Those five had experienced a severe exposure, such as a deep injection wound or a puncture from a grossly contaminated large-bore biopsy needle. None of the workers who had direct exposure of mucous membrane to blood or other body fluid developed infection.
Hemophilia, a genetic disorder marked by the absence of an important clotting factor, results in repeated bleeds, often into joints. Transfusions of blood products can correct the bleeding temporarily. Before routine screening of blood and blood products for the AIDS virus was initiated in 1985, many hemophiliacs became infected. Since then, the risk has been virtually eliminated.
Casual Contact: How Aids Is Not Transmitted
Detection of the AIDS virus in saliva in 1984, and subsequently in tears, sparked immediate public concern. But further research has shown that the virus is rarely present in either. When it is, the quantity is minute probably too low, say most public-health experts, to play a role in infection. Nevertheless, as a precaution, they still warn against deep kissing with an infected person and advise special procedures for eye-care and dental personnel, who are constantly exposed to tears or saliva.
No such precautions apply to contact with drinking glasses, eating utensils, eyeglasses, and the like. All evidence shows that the risk from such items is nonexistent. The same is true for a typical friendly kiss.
Some parents of young schoolchildren also fear that a bite from an infected classmate might transmit the virus. Here again, the concern is unwarranted, experts at the CDC say. The amount of virus in saliva—if any—is considered too minuscule to cause infection, especially in a single instance of biting.
There is no evidence that the virus can be transmitted by food or by any variety of insect. Nurses who have administered mouth-to-mouth resuscitation to AIDS patients have not become infected. Nor have children attending school with hemophiliac classmates who were infected. But possibly the strongest evidence that the virus presents no threat in casual contact comes from studies in families.
If AIDS could spread through casual contact, a patient's home would be a likely breeding ground of infection. The close personal environment of a family household would offer ample opportunities for spreading the virus.
It hasn't happened, however. Studies in U.S. households and among families in Europe, Haiti, and central Africa have all produced the same result. No instance of transmission has occurred among anyone who wasn't the sexual partner or newborn infant of an infected person.
The most comprehensive study is an ongoing, long-term investigation being conducted jointly by the CDC, Montefiore, North Central Bronx Hospital, and Albert Einstein College of Medicine. In 1986, the research group reported its evaluation of 101 people living in households with 39 AIDS patients. None of the 101 household members were sexual partners of the patients, but all lived in close personal contact with the infected person for periods ranging from three months to four years.
"Most of the families in this study were poor and lived in crowded conditions," the researchers reported. "A high percentage of household members assisted the patient with bathing, dressing, and eating." There was close personal interaction, and substantial sharing of household facilities and items likely to be soiled with body secretions. Some of the household members used the same razors and toothbrushes as the patient. Many shared the same combs, eating utensils, plates, and drinking glasses. More than 90 percent used the same toilet, bath, and kitchen facilities as the patient, and 37 percent shared the same bed. Most also engaged in affectionate behavior with the patient, including hugging and kissing on the cheek or lips.
Except for one child infected at birth, all of the 101 households examined were found to be free of any sign of AIDS virus in their blood. The researchers concluded that transmission of the virus through ordinary personal contact "appears to be minimal or nonexistent in the household setting."
The research group has continued its investigation since that report. As of the spring of 1988, it had completed examinations of more than 200 family members in more than 75 households, including reexaminations of the original subjects. None (except the one child) showed evidence of infection.
Similar findings were recently reported from central Africa. A research group in Kinshasa, Zaire, investigated whether the same results reported among household members in Europe and North America apply under conditions common in the developing world.
"Unlike living conditions in the United States and Europe," said the report, "living conditions in households in Kinshasa are more likely to include environmental factors favoring person-to-person transmission of infectious agents." Such conditions, the report said, included "crowding, lack of modern sanitary systems, and substantial numbers of mosquitoes and other arthropods."
The study, which evaluated 204 household members of AIDS patients, found no evidence that the virus was spread by ordinary personal contact. The researchers concluded that transmission by nonsexual personal contact "appears to be very rare, if it occurs at all."
The Kinshasa group also suggested what many American and European epidemiologists have come to realize, with profound relief: Since the AIDS virus isn't spreading in the home, transmission by casual contact in workplaces, schools, or similar settings will probably never occur.
Federal health officials stress that the AIDS virus has spread almost exclusively by three routes: by sexual intercourse, through blood contact (contamination with or transfusion of infected blood or blood products), and from an infected pregnant woman to her fetus or newborn. The only other known instances in which the virus was transmitted, say officials, involved artificial insemination or organ transplants from infected donors.
But many people remain unconvinced. They fear that casual personal contact with an AIDS victim—a handshake, a sneeze, a drink from the same glass might lead to infection. A child with AIDS attempting to attend school can throw a community into a frenzy. An AIDS patient returning to work may find coworkers deserting the job in protest.
In short, anxiety about AIDS has itself become epidemic. Part of the problem is that AIDS is a new disease mysterious in its origin and initially baffling in its symptoms and cause. But the impression that scientists are groping amid a welter of unresolved questions is misleading. A vast amount of critical knowledge has already been gained about AIDS, and more is being learned all the time.
The epidemic first surfaced in the late 1970s, when rare cancers and uncommon infections began appearing in a number of gay (homosexual) men. Those illnesses were linked with a severe deficiency in the body's immune-defense system—a disorder initially called GRID, for Gay-Related Immune Deficiency. As late as mid-1981, gay men were still the only known victims in the United States, creating the impression that AIDS arose from something exclusive to that group.
By 1982, when the name became AIDS, for "acquired immune deficiency syndrome," the first currents of fear jolted the health-care community. The number of AIDS cases was rising geometrically, and the disease had appeared in two more groups—intravenous drug users and hemophiliacs. Not only did the pattern imply an infectious agent, but the disease was now affecting three of the principal groups vulnerable to hepatitis B infection—a viral illness that's also an occupational hazard among health workers.
AIDS would subsequently prove to be much less contagious than hepatitis B, partly because the number of hepatitis B virus particles in blood is up to a billion times greater than the number of AIDS virus particles. But no one knew that in 1982. Nor was it known that the AIDS virus doesn't penetrate intact skin or the linings of the respiratory and digestive tracts—and thus could not be transmitted by such things as a kiss on the lips, a cough, or food prepared by a person with AIDS.
With the number of cases doubling every six months, medical personnel on the front line became increasingly fearful for their own safety. That fear soon became evident to the public at large, helping to confirm impressions that a virulent plague was loose in the land. As public fear of the threat grew, scientific understanding of the disease advanced rapidly.
By mid-1984, three independent research teams in the United States and France had conclusively identified the virus that causes AIDS. Discovery of the virus—now designated "human immunodeficiency virus," or HIV—immediately opened new avenues of research into every aspect of the disease. Investigators have already deciphered the genetic code of the virus in search of ways to attack it. Others probing for clues to therapy have explored its crippling effect on the immune system.
For epidemiologists, who investigate the incidence, transmission, and patterns of disease, identification of the virus was the indispensable handle for a powerful new tool. It meant that a test could now be developed to detect individual exposure to the virus, information vital for deeper insight into the epidemic and its spread.
Elisa: Testing for Exposure to Aids
By 1985, a simple, inexpensive blood test for detecting exposure to the AIDS virus had been developed and approved for use. Called ELISA (for enzyme-linked immunosorbent assay), the test detects antibodies produced by white blood cells in response to the presence of the virus. Developed primarily to screen potential blood donors, ELISA has also served as a versatile research tool, greatly facilitating analysis of the epidemic's path.
Before ELISA, it was difficult to trace the spread of the virus. There was no practical way to detect it in people without symptoms, who represent the largest number of those infected. By mid-1988, about 65,000 cases of AIDS had been reported to the U.S. Centers for Disease Control (CDC). An estimated 325,000 people had AIDS-related complex (ARC), a term used to describe a condition that includes (in addition to laboratory evidence of immunodeficiency) swollen glands, recurrent fever, weight loss, or a combination of those symptoms. When persons with ARC develop any one of a number of opportunistic infections (or Kaposi's sarcoma), they are considered to have developed AIDS.
An estimated 1.6 million to 3.2 million additional people may be infected with the virus but have no symptoms of illness. Although their blood reveals antibodies to the virus—as determined by two consistently positive ELISA tests and a more sophisticated (and costly) confirming test called Western blot analysis—they may have no other laboratory or clinical signs of disease. Most public-health officials estimate that 30 to 50 percent of those people will ultimately develop full-blown AIDS.
With a practical means of detection in hand, researchers began probing areas previously obscure. For example, how fast was the virus spreading to the general population—or among intravenous-drug users, or gay men? Was it infecting family members who had no sexual contact with a victim in the home? Were some sexual practices riskier than others? Since 1985, a wealth of new information has become available to address those questions and others.
Some of the findings are uncompromisingly bleak. Among high-risk groups, the AIDS virus is cutting a widening swath of infection, particularly in areas that have already borne the brunt of the epidemic, such as metropolitan New York and San Francisco. The infection is also spreading among young adults in inner-city minority groups, especially black and Hispanic intravenous-drug users and their sexual partners. One analysis of blood tests administered to some 300,000 military recruits found the rate of infection in blacks to be four times that in whites.
Federal health officials have predicted that the cumulative total of AIDS cases could reach 270,000 by 1991, with 179,000 deaths. Most of those will be people who are already infected with the virus, the officials said.
The grim projections of unfolding tragedy have overshadowed all other emerging information about the epidemic. But there has been another side to the news. An increasing number of epidemiological studies now point to an unmistakable conclusion: The reassurances from health officials about casual contact with AIDS patients are well founded. As CDC director James O. Mason, M.D., put it, "This is a very difficult disease to catch."
Transmission appears to require not only direct insertion of the virus into the bloodstream but also a substantial dose of the virus much more than could be transmitted by casual contact. Indeed, a consistent pattern in people who become infected is frequent or severe exposure to the virus.
Even in sexual intercourse—the primary route of infection—the virus does not appear to spread easily. Like most sexually transmitted diseases, AIDS is strongly associated with a highly active sex life and multiple partners.
Homosexual Transmission
Among gay and bisexual men, the disease first appeared in those with extremely large numbers of sexual partners a lifetime average of over 1000 partners, according to one early epidemiologic study. It's not known whether multiple sexual contacts raise the risk simply by raising the odds that a person will encounter the AIDS virus once, or by some process in which the body's defenses are worn down (perhaps through exposure to other sexually transmitted diseases), or both. All that's known for sure is that having a large number of sexual partners raises the risk.
Now that the virus is more prevalent—and the odds of catching it (among people at risk) are higher—the average number of sexual partners reported by people who contract the disease would be far less than 1000. No precise numbers, however, are available.
A key factor in the rapid spread of the virus among gay and bisexual men is the practice of anal intercourse, probably because the surface membranes and blood vessels of the anal canal are vulnerable to small fissures or tears during intercourse. Such tears may allow virus carried in semen to gain entry into the bloodstream of the receiving partner. The risk of viral transmission is especially high for the partner accepting penetration (receptive anal intercourse). In one six-month study examining transmission of the virus in gay men, a University of Pittsburgh research team found receptive anal intercourse to be the major risk factor in infection. At the outset, none of the men showed any evidence of AIDS virus in their blood. After six months, however, antibodies to the virus were found in a number of the subjects, especially among men who had had two or more sexual partners. In that group, men engaging in receptive anal intercourse had 16 times the infection rate as those having no anal intercourse.
As yet, there's no scientific evidence that sexual practices other than anal-related sex lead to AIDS-virus transmission in gay men. However, only a few large studies have compared the effects of different sexual practices.
One such study was conducted by University of California researchers over a two-year period for the San Francisco Men's Health Study. The California investigators examined infection rates among some 800 gay or bisexual men with different sexual histories. No difference in infection rates was found between those who engaged solely in oral-genital sex and those who had no sexual partners at all.
The California researchers concluded that the risk of AIDS-virus transmission by oral-genital contact was minimal. But they cautioned—as did the Pittsburgh group—that their findings did not prove that sexual activity other than anal intercourse posed no risk among gay men. They pointed out that their results were based on a relatively small number of observations and could not completely exclude the possibility of transmission by oral-genital sex.
Indeed, caution has been the watchword among public-health officials offering preventive advice. Since more than 90 percent of AIDS cases have occurred in gay or bisexual men and intravenous-drug users, the message to those high-risk groups has stressed avoiding any possible risk. One drawback of that approach, however, is that it makes AIDS appear easier to catch than it actually is. Some public-health workers, for example, warn against deep kissing involving exchange of saliva. But there's no evidence that the virus is transmitted that way.
Heterosexual Transmission
In contrast to oral sex or deep kissing, vaginal intercourse is clearly an important route of infection. The AIDS virus can be spread by either a man or a woman during intercourse.
On a relative scale, vaginal intercourse appears to be less effective in spreading the virus than anal intercourse, and less contagious from female to male than the reverse. As yet, the risk of transmission in a single act of vaginal intercourse is unknown. But current evidence suggests that frequent or long-term sexual exposure with an infected partner or partners is an important factor in transmission.
As of mid-1988, about 4 percent of newly diagnosed AIDS cases in the U.S. can be traced to heterosexual transmission. A large number of the victims are spouses or long-term sexual partners of AIDS patients or other high-risk individuals, particularly intravenous-drug users. Another large segment includes immigrants from Haiti and central Africa, where the virus spreads mainly by heterosexual intercourse.
Some confusion initially surrounded the status of Haitians, who were once listed as a separate risk group for AIDS. Epidemiologists have since found that the infection rate is not high among Haitians who are longterm U.S. residents. It's high, though, among recent immigrants with a history of venereal disease or sexual contact with prostitutes. In both Haiti and central Africa, infected prostitutes are an important factor in the spread of the virus among heterosexuals.
Reports from central Africa also show that AIDS is concentrated among urban people who are very sexually active. The average AIDS patient had more than 30 sex partners a year, including frequent contacts with prostitutes.
Overall, heterosexual spread of the infection often involves multiple sexual exposures to the virus. Even under these circumstances, however, infection is far from automatic. In a number of studies based on antibody tests, 50 to 65 percent of the regular heterosexual partners of patients with AIDS or advanced AIDS-related illness have shown no evidence of the virus in their blood. And among the wives or regular sex partners of hemophiliacs with AIDS, 90 to 95 percent were not infected.
The fact that such prolonged sexual exposure often fails to cause infection certainly argues against fears that a bathtub, toilet seat, or the air around an AIDS patient could pose a threat.
Public-health officials generally recommend using condoms during anal or vaginal intercourse and oral-genital sex to reduce the risk of AIDS-virus transmission. CDC investigators, after evaluating many studies from around the world, concluded that barrier contraceptives—condoms, spermicides, and diaphragms used with spermicides—are effective in reducing the risk of sexually transmitted diseases, including AIDS. Lubricants, if used, should be water-based; petroleum products can damage latex.
One lab experiment demonstrated that the AIDS virus can't penetrate an intact latex condom. Another showed that a common spermicide, nonoxynol-9, inactivates the virus and kills the white blood cells that carry it. (Nonoxynol-9 is the spermicide in many contraceptive jellies and foams, and the active ingredient in the contraceptive sponge Today.)
Blood-to-Blood Contact
The rapid spread of the AIDS virus among intravenous-drug users fosters the impression that the virus is highly infectious. Actually, some common practices among addicts who use needles are what make them especially vulnerable. And while there is some evidence that gay people have modified their risk behavior, drug abusers have not.
In addition to the frequency of injections—at least daily in many users—intravenous-drug addicts often share their needles and syringes. Indiscriminate sharing of injection paraphernalia has become common at drug "shooting galleries," where addicts go to rent or share equipment. "Often, the same needle will be used for up to 50 injections until it is no longer usable," reports Peter Selwyn, M.D., medical director of a drug-treatment program for addicts at Montefiore Medical Center in the Bronx, New York.
The risk of contamination is multiplied by another practice—drawing blood back into the syringe so that any remaining drug can be flushed out of the syringe and into the vein. If an addict is infected with the virus, a significant dose of it may be transmitted to the next sharer. In short, intravenous-drug use is an extremely effective way of acquiring a blood-borne disease—even one as difficult to contract as AIDS.
Some people have proposed that government agencies should make sterile needles and syringes available to intravenous-drug users, either free or at cost. Facing the threat of an AIDS epidemic in 1984, the Amsterdam (Netherlands) Municipal Health Service adopted such a plan. It appears to be working. The number of addicts using intravenous drugs has not increased, and more addicts than ever have been motivated to enter treatment for their addiction. Similar programs have since been initiated in Sweden, Great Britain, France, Italy, and Australia.
Such proposals in the United States have generally met with strong opposition. In 1988, the first attempt at a free-needle program was made in Portland, Oregon; it stalled when insurance coverage was refused. New York City began a similar program the same year. Yet even advocates of the idea recognize it as a stopgap measure. They emphasize the need for more drug-treatment centers and a multifaceted approach to the problem. But an epidemic often demands swift action. Cheap, clean needles and syringes would at least reach the inner-city battleground where AIDS has hit hardest and where the real war on drugs is being fought—and lost.
The experience of health-care workers, meanwhile, provides a striking contrast to the epidemic among intravenous-drug users. Seven separate studies in the United States and England have examined the outcome of needle-stick and other exposures among health workers caring for AIDS patients. Approximately 1500 people—nurses, physicians, medical students, technicians, and laboratory workers—were studied to determine whether their exposures had resulted in infection. Most of the exposures were needle-stick injuries from instruments that had just been used for an AIDS patient. The rest were direct exposures of a mucous membrane, such as a splash of infected blood into the eye or nostrils.
Despite the large number of exposures, only five of the 1500 workers developed AIDS-virus antibodies in their blood. Those five had experienced a severe exposure, such as a deep injection wound or a puncture from a grossly contaminated large-bore biopsy needle. None of the workers who had direct exposure of mucous membrane to blood or other body fluid developed infection.
Hemophilia, a genetic disorder marked by the absence of an important clotting factor, results in repeated bleeds, often into joints. Transfusions of blood products can correct the bleeding temporarily. Before routine screening of blood and blood products for the AIDS virus was initiated in 1985, many hemophiliacs became infected. Since then, the risk has been virtually eliminated.
Casual Contact: How Aids Is Not Transmitted
Detection of the AIDS virus in saliva in 1984, and subsequently in tears, sparked immediate public concern. But further research has shown that the virus is rarely present in either. When it is, the quantity is minute probably too low, say most public-health experts, to play a role in infection. Nevertheless, as a precaution, they still warn against deep kissing with an infected person and advise special procedures for eye-care and dental personnel, who are constantly exposed to tears or saliva.
No such precautions apply to contact with drinking glasses, eating utensils, eyeglasses, and the like. All evidence shows that the risk from such items is nonexistent. The same is true for a typical friendly kiss.
Some parents of young schoolchildren also fear that a bite from an infected classmate might transmit the virus. Here again, the concern is unwarranted, experts at the CDC say. The amount of virus in saliva—if any—is considered too minuscule to cause infection, especially in a single instance of biting.
There is no evidence that the virus can be transmitted by food or by any variety of insect. Nurses who have administered mouth-to-mouth resuscitation to AIDS patients have not become infected. Nor have children attending school with hemophiliac classmates who were infected. But possibly the strongest evidence that the virus presents no threat in casual contact comes from studies in families.
If AIDS could spread through casual contact, a patient's home would be a likely breeding ground of infection. The close personal environment of a family household would offer ample opportunities for spreading the virus.
It hasn't happened, however. Studies in U.S. households and among families in Europe, Haiti, and central Africa have all produced the same result. No instance of transmission has occurred among anyone who wasn't the sexual partner or newborn infant of an infected person.
The most comprehensive study is an ongoing, long-term investigation being conducted jointly by the CDC, Montefiore, North Central Bronx Hospital, and Albert Einstein College of Medicine. In 1986, the research group reported its evaluation of 101 people living in households with 39 AIDS patients. None of the 101 household members were sexual partners of the patients, but all lived in close personal contact with the infected person for periods ranging from three months to four years.
"Most of the families in this study were poor and lived in crowded conditions," the researchers reported. "A high percentage of household members assisted the patient with bathing, dressing, and eating." There was close personal interaction, and substantial sharing of household facilities and items likely to be soiled with body secretions. Some of the household members used the same razors and toothbrushes as the patient. Many shared the same combs, eating utensils, plates, and drinking glasses. More than 90 percent used the same toilet, bath, and kitchen facilities as the patient, and 37 percent shared the same bed. Most also engaged in affectionate behavior with the patient, including hugging and kissing on the cheek or lips.
Except for one child infected at birth, all of the 101 households examined were found to be free of any sign of AIDS virus in their blood. The researchers concluded that transmission of the virus through ordinary personal contact "appears to be minimal or nonexistent in the household setting."
The research group has continued its investigation since that report. As of the spring of 1988, it had completed examinations of more than 200 family members in more than 75 households, including reexaminations of the original subjects. None (except the one child) showed evidence of infection.
Similar findings were recently reported from central Africa. A research group in Kinshasa, Zaire, investigated whether the same results reported among household members in Europe and North America apply under conditions common in the developing world.
"Unlike living conditions in the United States and Europe," said the report, "living conditions in households in Kinshasa are more likely to include environmental factors favoring person-to-person transmission of infectious agents." Such conditions, the report said, included "crowding, lack of modern sanitary systems, and substantial numbers of mosquitoes and other arthropods."
The study, which evaluated 204 household members of AIDS patients, found no evidence that the virus was spread by ordinary personal contact. The researchers concluded that transmission by nonsexual personal contact "appears to be very rare, if it occurs at all."
The Kinshasa group also suggested what many American and European epidemiologists have come to realize, with profound relief: Since the AIDS virus isn't spreading in the home, transmission by casual contact in workplaces, schools, or similar settings will probably never occur.
Famous People Who Died of Aids
Rock Hudson (died 1985) – Rock Hudson was an American actor who starred in many films and several TV programmes. He was well renowned for his role in romantic comedies and as a romantic leading man (often acting opposite Doris Day), playing of his masculine looks. He was voted ‘Star of the Year’, ‘Favourite Leading Man’ and many other roles and completed around 70 films over four decades making him something of a Carry Grant-type figure. It was ironic in a way then that for all this time he was hiding his homosexuality and would succumb to, and eventually die of, AIDS at the age of 60.
Kimberly Bergalis (died 1991) – Kimberly Bergalis is an unusual addition to this list as someone whose fame actually came from their experience with AIDS as someone who would become a pivotal symbol in the debate regarding AIDS testing for health professionals. With no celebrity status before her debacle, it was a tragic way to acquire fame.
As the eldest of three daughters, Bergalis was born in 1978 and attended the University of Florida to major in business. Here she had two serious boyfriends but never lost her virginity and had never used any kind of drugs. In 1987 she had two molars removed by her dentist Dr David J Acer. Tragically, Dr Acer had been diagnosed with AIDS that year and shortly after Bergalis began to show symptoms herself. CDC tests suggested that it was Acer who infected Bergalis and several of his other patients. HIV can spread from patient to doctor, doctor to patient or even patient to patient via reusing unsterilized instruments (scalpels, hypodermic needles etc). Today almost all such instruments are disposable.
Freddie Mercury (died 1991) – Lead singer, composer, instrumentalist and front man in the band ‘Queen’, Freddie Mercury was a flamboyant and outwardly gay rock star who had many hits and achieved a high level of fame. Among his most successful hits were Bohemian Rhapsody, Killer Queen, Somebody to Love, Don’t Stop Me Now, We Are the Champions, Crazy Little Thing Called Love. When he was diagnosed as HIV positive he decided to hide this status from the general public and didn’t announce his illness until the day before he died which was a source of controversy among those who though he could raise awareness for illness. However his illness did find its way into the lyrics of his songs with tracks such as ‘The Show Must Go On’ and the never completed album ‘Made in Heaven’ strongly indicating his terminal condition.
Liberace (died 1987) – Liberace was a famous pianist and entertainer of Italian and Polish descent and was the highest paid entertainer in the world around the same time that Elvis and the Beatles. He public denied being homosexual (though it’s highly likely that he in fact was) and it remains a mystery how and when he became HIV positive.
Kimberly Bergalis (died 1991) – Kimberly Bergalis is an unusual addition to this list as someone whose fame actually came from their experience with AIDS as someone who would become a pivotal symbol in the debate regarding AIDS testing for health professionals. With no celebrity status before her debacle, it was a tragic way to acquire fame.
As the eldest of three daughters, Bergalis was born in 1978 and attended the University of Florida to major in business. Here she had two serious boyfriends but never lost her virginity and had never used any kind of drugs. In 1987 she had two molars removed by her dentist Dr David J Acer. Tragically, Dr Acer had been diagnosed with AIDS that year and shortly after Bergalis began to show symptoms herself. CDC tests suggested that it was Acer who infected Bergalis and several of his other patients. HIV can spread from patient to doctor, doctor to patient or even patient to patient via reusing unsterilized instruments (scalpels, hypodermic needles etc). Today almost all such instruments are disposable.
Freddie Mercury (died 1991) – Lead singer, composer, instrumentalist and front man in the band ‘Queen’, Freddie Mercury was a flamboyant and outwardly gay rock star who had many hits and achieved a high level of fame. Among his most successful hits were Bohemian Rhapsody, Killer Queen, Somebody to Love, Don’t Stop Me Now, We Are the Champions, Crazy Little Thing Called Love. When he was diagnosed as HIV positive he decided to hide this status from the general public and didn’t announce his illness until the day before he died which was a source of controversy among those who though he could raise awareness for illness. However his illness did find its way into the lyrics of his songs with tracks such as ‘The Show Must Go On’ and the never completed album ‘Made in Heaven’ strongly indicating his terminal condition.
Liberace (died 1987) – Liberace was a famous pianist and entertainer of Italian and Polish descent and was the highest paid entertainer in the world around the same time that Elvis and the Beatles. He public denied being homosexual (though it’s highly likely that he in fact was) and it remains a mystery how and when he became HIV positive.
HIV Rash – Symptoms, Description and Information
HIV has long been difficult to diagnose with no consistent or obvious symptoms. However in some cases a rash will develop that can help indicate the existence of the HIV virus, while in others it may be the result of the drugs used to control the condition. In both these cases the rash is known as a ‘HIV rash’. Roughly 80% of HIV sufferers will get some kind of rash associated with their condition.
In those cases where the rash is a symptom of the HIV itself, rather than the medication, it will appear during the ‘sero-conversion’ of the infection. This is the point at which antibodies are developed by the body in order to try to combat the infected cells. This will tend to occur around three weeks into the infectio, though in some cases it might be much later.
The rash itself will then appear as a slightly raised area, dark red in colour, and made up of many tiny ‘pauples’ much like many other rashes (for those with a dark skin tone the rash may alternatively be dark brown). This type of rash is known as a maculpapular rash and can occur on any part of the body – usually the face and trunk and occasionally the hands and feet. Sometimes it might also cause ulcers in the mouth. The rash itself is likely to itch making it quite unpleasant.
The significance of the HIV rash is a) that it can indicate the presence of HIV in combination with other symptoms, and b) that it indicates the start of the sero-conversion which means a patient is more likely to test positive for the illness. For all these reasons a HIV rash will significantly increase your chances of diagnosis.
Those other symptoms will mostly be flu-like symptoms along with fever, diarrhoea, enlarged lymph nodes, headaches, oral thrush (which looks like white spots in the mouth) and myalgia (muscle ache). In a recent study of 258 people screened for HIV it was shown that a fever in combination with a rash was the best clinical guide to HIV, presenting the best chance of an accurate diagnosis.
Rashes caused by the HIV medication however are slightly different. These ‘drug eruptions’ will see the patients experience raised reddish lesions that look like rashes which will cover the whole body. This is often a reaction to Co-trimoxazole which is used to treat the PCP pneumonia in HIV sufferers.
If you already have HIV then and you develop a rash similar in description to those described here then this is likely the HIV rash, though you should see your doctor to make sure. If you get one of these rashes and you are not HIV positive as far as you are aware, but have reason to suspect you could be and this coincides with fever and flu like symptoms, then you may be suffering from HIV and should see a doctor immediately.
Unfortunately there is no cure for HIV and the condition can only be managed using highly regular medication. This means that many people are forced to live with the HIV rash as part of themselves. There are however some things you can do to make it more pleasant. For example use over-the-counter medication such as Benadrul or Hydrocortisone Cream which will shrink the rashes and lessen itching. Also try to avoid heat where possible including hot showers and baths and direct sunlight as these can aggravate the rash. If your rash coincides with the beginning of a new course of drugs, foods or soaps, then you might have identified an allergy. If you suspect a particular medication is causing this then you may want to speak to your doctor about alternative medications you can use instead (in other cases the rash will not be enough of an issue to warrant a change of drugs, but where there is an obvious alternative it might).
The HIV rash then is an unpleasant side effect of a serious condition then, but can be an invaluable tool in identifying the condition. While HIV sufferers will likely have to live with the rash there are many ways to help manage it.
In those cases where the rash is a symptom of the HIV itself, rather than the medication, it will appear during the ‘sero-conversion’ of the infection. This is the point at which antibodies are developed by the body in order to try to combat the infected cells. This will tend to occur around three weeks into the infectio, though in some cases it might be much later.
The rash itself will then appear as a slightly raised area, dark red in colour, and made up of many tiny ‘pauples’ much like many other rashes (for those with a dark skin tone the rash may alternatively be dark brown). This type of rash is known as a maculpapular rash and can occur on any part of the body – usually the face and trunk and occasionally the hands and feet. Sometimes it might also cause ulcers in the mouth. The rash itself is likely to itch making it quite unpleasant.
The significance of the HIV rash is a) that it can indicate the presence of HIV in combination with other symptoms, and b) that it indicates the start of the sero-conversion which means a patient is more likely to test positive for the illness. For all these reasons a HIV rash will significantly increase your chances of diagnosis.
Those other symptoms will mostly be flu-like symptoms along with fever, diarrhoea, enlarged lymph nodes, headaches, oral thrush (which looks like white spots in the mouth) and myalgia (muscle ache). In a recent study of 258 people screened for HIV it was shown that a fever in combination with a rash was the best clinical guide to HIV, presenting the best chance of an accurate diagnosis.
Rashes caused by the HIV medication however are slightly different. These ‘drug eruptions’ will see the patients experience raised reddish lesions that look like rashes which will cover the whole body. This is often a reaction to Co-trimoxazole which is used to treat the PCP pneumonia in HIV sufferers.
If you already have HIV then and you develop a rash similar in description to those described here then this is likely the HIV rash, though you should see your doctor to make sure. If you get one of these rashes and you are not HIV positive as far as you are aware, but have reason to suspect you could be and this coincides with fever and flu like symptoms, then you may be suffering from HIV and should see a doctor immediately.
Unfortunately there is no cure for HIV and the condition can only be managed using highly regular medication. This means that many people are forced to live with the HIV rash as part of themselves. There are however some things you can do to make it more pleasant. For example use over-the-counter medication such as Benadrul or Hydrocortisone Cream which will shrink the rashes and lessen itching. Also try to avoid heat where possible including hot showers and baths and direct sunlight as these can aggravate the rash. If your rash coincides with the beginning of a new course of drugs, foods or soaps, then you might have identified an allergy. If you suspect a particular medication is causing this then you may want to speak to your doctor about alternative medications you can use instead (in other cases the rash will not be enough of an issue to warrant a change of drugs, but where there is an obvious alternative it might).
The HIV rash then is an unpleasant side effect of a serious condition then, but can be an invaluable tool in identifying the condition. While HIV sufferers will likely have to live with the rash there are many ways to help manage it.
Cure for HIV
HIV, or 'human immunodeficiency virus', is a serious virus that is most known for its role in causing AIDS – a condition that causes the progressive failure of the immune system and that leads to potentially threatening infections and cancers to occur. Often HIV and AIDS are used interchangeably for this reason, though technically the two are very different conditions. HIV is a very serious condition that is caused through blood transfusions, breast milk, and the exchange of sexual fluids where it is present as a free virus and a virus within infected immune cells.
HIV is a very serious threat and has been the cause of many deaths in the West and particularly in the developing world. It is classed as a 'pandemic' and between its discovery in 1981 and 2006, AIDS was responsible for the deaths of over 25 million people. Many people continue to suffer with HIV and AIDS today, and it currently affects around 0.6% of the population. In 2009 alone it claimed around 1.8 million lives.
All of this means that a potential cure for AIDS would be fantastic news that could change the lives of millions of people each year and prevent millions more deaths. While there is currently no cure for HIV, recent developments and research has meant that people can live with AIDS and HIV much longer than they could ever before, while at the same time further research is looking into promising potential cures that might be available in the future.
While there currently is no cure for AIDS, there are nevertheless many management techniques in place. Treatment will normally consist of 'highly active antiretroviral therapy' which is taken as a combination of three or more drugs which are of particular classes of antiretroviral agent. Therapy should be begun as soon as possible and at the point where the CD4 count falls below 500. When therapy is deferred death rates are twice as high. However these therapies are lifelong commitments and have a range of risks and benefits. If treatment is stopped even temporarily then high levels of HIV-1 often return and are at this point then HAART resistance – so adherence to the medication is highly important. If treatment is started by the time that the CD4 count falls below 350 then the life expectancy is 32 years, though this is higher for those who start earlier. Without HAART, HIV will progress to AIDS after around 9-10 years and at this point life expectancy is only 9.2 months.
The promise of cures being available for HIV in the future then is something that is highly hopeful for patients and that could transform their lives. While there is no cure currently known, studies and research have shown a lot of promise. Here we will look at some of the research that is currently being done into potential cures for HIV and AIDS.
In 2007 Timothy Ray Brown, a 40 year old HIV positive man, was given a bone marrow stem cell transplant in order to treat acute myelogenous leukemia (AML) and after a relapse was given a second transplant. The donor had a CCR5-A32 mutation which gave him resistance to HIV infection. 20 months later and with no other treatments the HIV levels in the patient's blood had dropped to below the limit for detection. Whether this is a cure, or whether the virus remained hidden in the tissue is unsure. While this is potentially very promising, there is a mortality risk currently associated with stem cell transplant, and there is also a lot of difficulty with finding suitable donors.
Immunotherapies are aimed at altering the function of the immune system, and some have shown promise for helping the immune system to recover from HIV such as 'Interleukin 7'. This is a hematopoietic growth factor that is secreted by stromal cells of the red marrow and thymus. Research is currently ongoing. It has currently entered the phrase 2 clinical trial used with two antiretroviral drugs. The hope is that IL-7 can target and destroy latently infected cells, and this could result in the reduction of HIV or even in the total eradication.
HIV is a very serious threat and has been the cause of many deaths in the West and particularly in the developing world. It is classed as a 'pandemic' and between its discovery in 1981 and 2006, AIDS was responsible for the deaths of over 25 million people. Many people continue to suffer with HIV and AIDS today, and it currently affects around 0.6% of the population. In 2009 alone it claimed around 1.8 million lives.
All of this means that a potential cure for AIDS would be fantastic news that could change the lives of millions of people each year and prevent millions more deaths. While there is currently no cure for HIV, recent developments and research has meant that people can live with AIDS and HIV much longer than they could ever before, while at the same time further research is looking into promising potential cures that might be available in the future.
Current Management Techniques
While there currently is no cure for AIDS, there are nevertheless many management techniques in place. Treatment will normally consist of 'highly active antiretroviral therapy' which is taken as a combination of three or more drugs which are of particular classes of antiretroviral agent. Therapy should be begun as soon as possible and at the point where the CD4 count falls below 500. When therapy is deferred death rates are twice as high. However these therapies are lifelong commitments and have a range of risks and benefits. If treatment is stopped even temporarily then high levels of HIV-1 often return and are at this point then HAART resistance – so adherence to the medication is highly important. If treatment is started by the time that the CD4 count falls below 350 then the life expectancy is 32 years, though this is higher for those who start earlier. Without HAART, HIV will progress to AIDS after around 9-10 years and at this point life expectancy is only 9.2 months.
Future Cures
The promise of cures being available for HIV in the future then is something that is highly hopeful for patients and that could transform their lives. While there is no cure currently known, studies and research have shown a lot of promise. Here we will look at some of the research that is currently being done into potential cures for HIV and AIDS.
Stem Cells
In 2007 Timothy Ray Brown, a 40 year old HIV positive man, was given a bone marrow stem cell transplant in order to treat acute myelogenous leukemia (AML) and after a relapse was given a second transplant. The donor had a CCR5-A32 mutation which gave him resistance to HIV infection. 20 months later and with no other treatments the HIV levels in the patient's blood had dropped to below the limit for detection. Whether this is a cure, or whether the virus remained hidden in the tissue is unsure. While this is potentially very promising, there is a mortality risk currently associated with stem cell transplant, and there is also a lot of difficulty with finding suitable donors.
Immunomodulatory Agents
Immunotherapies are aimed at altering the function of the immune system, and some have shown promise for helping the immune system to recover from HIV such as 'Interleukin 7'. This is a hematopoietic growth factor that is secreted by stromal cells of the red marrow and thymus. Research is currently ongoing. It has currently entered the phrase 2 clinical trial used with two antiretroviral drugs. The hope is that IL-7 can target and destroy latently infected cells, and this could result in the reduction of HIV or even in the total eradication.
Subscribe to:
Posts (Atom)