Dont just blame the chickens for flu
Mon, 24 Mar 2008 21:45:50 GMTBy KEVIN FREKING, Associated Press Writer
WASHINGTON - Intensive rice farming and large duck populations — not the number of chickens raised — may be the best predictors of where bird flu might develop in Southeast Asia, according to researchers reviewing outbreaks in Vietnam and Thailand.
About 140 million birds in Southeast Asia have been killed in recent years to prevent the H5N1 virus from spreading. Researchers are trying to understand what factors have contributed to continued outbreaks despite significant control efforts.
By isolating those factors, policymakers can better target efforts to stem or prevent future outbreaks. For example, they could limit the movement of ducks into the rice paddies at certain times of the year, which would reduce the prospects of the virus being exchanged between domestic ducks and wild birds.
Researchers reviewed three outbreaks in early 2004 through late 2005. They looked at five variables: duck abundance, human population, chicken numbers, elevation and rice cropping intensity.
The researchers concluded that monitoring duck populations for H5N1 and tracking rice paddies by satellite were the best ways to predict where outbreaks were most likely to occur. They said that chickens are no longer a "highly significant predictor" of the presence of the H5N1 virus for Vietnam and Thailand.
"Essentially, is so pathogenic in chickens that it kills them before they can spread it," said Marius Gilbert of the Free University of Brussels, Belgium.
The outbreaks were most concentrated in regions where rice is cultivated two or three times a year.
"Rice paddy fields are an important habitat of free-ranging ducks, but also for wild waterfowl exploiting the same food resource in the wintering season," the researchers said. "Thus, they may form a critical risk factor in ... virus introduction, persistence and spread."
The researchers described the predictive power of their models as "moderate." They also said that their work appeared to warrant development of maps in other Southeast Asian countries identifying those areas most susceptible to future bird flu outbreaks.
Since 2003, bird flu has killed at least 236 people. Although it has been hard for people to catch, experts worry the virus could mutate into a form that passes easily among humans, sparking a pandemic. So far, most human cases have been linked to contact with infected birds.
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On the Net:
Proceedings of the National Academy of Sciences of the United States of America:
http://www.pnas.org
Tapwater salmonella inquiry narrows
Tue, 25 Mar 2008 02:03:11 GMTALAMOSA, Colo. - Officials said Monday they have ruled out wastewater contamination, disgruntled workers and terrorism as sources of salmonella bacteria in drinking water that have sickened more than 200 people.
A plan to disinfect the municipal water system will begin Tuesday as crews start running chlorine through it, Lisa Stigall, a spokeswoman with the state emergency response team, said Monday.
The roughly 8,500 residents of the southern Colorado town won't be able to drink the water until the chemical is washed out. That could take three weeks.
The number of cases was 217, with 68 confirmed through lab tests, said state health department spokeswoman Lori Maldonado. Nine people have required hospital treatment, and one remains in the hospital.
Test results Monday confirmed earlier findings of salmonella in the city's tap water.
The aquifer that's the town's water source appeared to be fine, Stigall said.
"There are many unknowns," Stigall said. "Many questions will be answered as they move through this process."
The first salmonella victim began showing symptoms around March 8, and state health officials became aware of the outbreak a week later, said Ned Calonge, the health department's chief medical officer.
Alamosa residents were told March 19 that they should not drink the water but that they could bathe in it if they didn't ingest it. Neighboring communities, businesses and the Colorado National Guard have trucked in bottled water and tankers.
The bacteria are typically spread by food. Salmonella can cause diarrhea, fever and stomach pain. Victims generally recover on their own, but the elderly, infants and people with impaired immune systems may require treatment.
Alamosa is about 160 miles south of Denver.
UN chief urges global fight against TB
Mon, 24 Mar 2008 21:44:50 GMTBy EDITH M. LEDERER, Associated Press Writer
UNITED NATIONS - The U.N. secretary-general on Monday urged stepped-up action to stop the global tuberculosis epidemic that is killing 4,000 people every day.
In a message marking World TB Day, Ban Ki-moon said "the man-made multi-drug resistant strain and its even more lethal form, extensively drug-resistant TB, are both spreading."
"That is why the theme of this year's day is `I Am Stopping TB'," he said. "This is a fight that can be won only with the collective commitment of millions of individuals — donors and researchers, doctors and health care workers, patients and family members."
Tuberculosis is an infectious disease caused by bacteria that attack the lungs. It is spread through the air and typically requires six to 18 months of treatment. The extensively drug-resistant strain is virtually untreatable in poor countries.
In a report last week, the World Health Organization said the fight to control TB has slowed. It said the rate of new cases fell by less than 1 percent between 2005 and 2006, which WHO called "very modest."
"Thanks to a broad coalition of partners working to stop TB, the proportion of people who become ill with the disease is slowly falling," Ban said. "But this progress is not keeping pace with population growth, so more and more people are becoming infected with tuberculosis."
"World TB Day is an occasion to urge action to stop tuberculosis, a disease which still kills an appalling 4,000 people every day," he said.
In 2006, there were an estimated 9.2 million new tuberculosis cases and 1.5 million deaths, the WHO said. India and China report the most cases, followed by Indonesia, South Africa and Nigeria.
Mon, 24 Mar 2008 21:49:05 GMT
By MARIA CHENG, AP Medical Writer
LONDON - Britain plans to force pharmaceutical companies to share more information with regulators about clinical trials after an investigation recently concluded that GlaxoSmithKline PLC deliberately withheld information about an antidepressant.
The four-year probe by the Medicines and Healthcare products Regulatory Agency, completed earlier this month, said the British company should have revealed more quickly that Seroxat sometimes increased the suicide risk in teenagers — by more than six times.
But without stronger legislation in place, the MHRA admitted there is no chance of prosecuting the company for what the agency perceives as an ethical lapse.
"I remain concerned that GSK could and should have reported this information earlier than they did," MHRA chief executive Kent Woods said in a statement.
GlaxoSmithKline rejected the suggestion that it withheld information.
"We firmly believe we acted properly and responsibly," said Dr. Alastair Benbow, the company's European medical director.
British legislation only obliges companies to report side effects in patients for which drugs are officially recommended.
Because Seroxat was only recommended for adults, GlaxoSmithKline was not required to report on any dangerous side effects it found in adolescents.
But Seroxat can still be given to adolescents if prescribed by a doctor. About half of psychiatric drugs are prescribed "off-label," meaning that doctors give them to patients for whom the drug is not strictly intended.
The MHRA said it sifted through more than 1 million pages of evidence after requesting details of clinical trials held between 1994 and 2002.
In response, Britain's government declared that by the end of the year, it will tighten laws forcing companies to share all their relevant safety research with regulators.
"Companies that conduct clinical trials should not compromise people's health by withholding information," public health minister Dawn Primarolo said. The new laws will require companies to disclose a drug's side effects in all patients tested, Primarolo said.
The GlaxoSmithKline case underlines a growing concern among many health experts that drug companies' tendency to hide damaging data could have disastrous consequences.
"If we make the wrong licensing decisions for whatever reasons, then patients may be put at risk," said Dr. Hans-Georg Eichler, senior medical officer at the European Medicines Agency, which licenses drugs across Europe.
Others warn that without more complete information from drug companies, consumers might see similar unpleasant surprises in the future.
"It would be unwise to assume that this particular case was anomalous," said Dr. Ike Iheanacho, editor of the Drug and Therapeutics Bulletin, an independent publication of the British Medical Journal that tracks drug treatments.
"It's perfectly reasonable for people to be anxious about what other drugs on the market might be questionable," he said.
Patients could be taking drugs they do not need or do not work, said Irving Kirsch, a professor of psychology at Britain's University of Hull and lead author of a study that concluded antidepressants like Prozac are mostly ineffective.
Kirsch and colleagues analyzed data about popular antidepressants after submitting a Freedom of Information Act request to the U.S. Food and Drug Administration. They found that depressed patients taking drugs did not actually do much better than those taking fake pills.
GlaxoSmithKline, makers of numerous antidepressants, responded in a statement that Kirsch's conclusions were incorrect because they evaluated only "a small subset of the data available."
But Kirsch and colleagues looked at nearly all the research submitted to the FDA. If that was only a small subset, experts wonder what other data might be out there.
"If we don't know what companies are doing, how do we know what's being reported?" said Davina Ghersi, coordinator of the World Health Organization's clinical trials registry platform.
Britain's National Institute for Clinical Excellence, the agency responsible for deciding what the health system pays for, issued guidelines on antidepressants in 2004. At the time, it did not have access to all the trial data.
"I shared with them the studies I had, but they did not have sufficient information to do a complete review," said Kirsch, then a consultant to the agency.
In recent years, once-blockbuster drugs, such as the painkiller Vioxx and the diabetes pill Avandia, have revealed worrying side effects, including significantly boosting the risk of a heart attack, years after being on the market.
"If we had seen all of the data in the first place, people might have realized that the claims being made for the drug were overblown and coy to the point of being fraudulent," said Dr. David Healy, a professor of psychiatry at Cardiff University in Wales.
But scapegoating of the drug companies may be too simplistic.
"A drug may turn out to be unsafe not because anyone has done anything wrong, but because new knowledge surfaces," Eichler said. Until a drug has been used by millions of people, the rarest and deadliest side effects may remain unknown.
Licenses are granted for drugs based on limited testing, Eichler said. Post-license monitoring should help sort out which drugs may be particularly risky, he said.
Without more data, people should be wary of what medications they take, experts say.
"If we had an overall picture, we might have a very different view about how good certain drugs are," Healy said. "There's an awful lot of people taking drugs that we don't know everything about."
Obese Women Less Likely to Be Tested for Some Cancers
Tue, 25 Mar 2008 03:47:04 GMTBy Randy Dotinga
HealthDay Reporter
MONDAY, March 24 -- A new review of 32 studies suggests that obese women -- particularly white women -- are more likely than others to skip screenings for breast and cervical cancer.
No one knows why extra pounds heighten the likelihood that women will avoid mammograms or Pap smears. And it's not known why obesity seems to have no significant effect on colorectal screening, the researchers said.
However, the findings do point to a problem that deserves attention in the doctor's office, said study lead author Sarah S. Cohen, a graduate student in the department of epidemiology at the University of North Carolina at Chapel Hill.
"Because obesity is becoming an increasing problem in our health-care system, encouraging women who are overweight and obese to be screened may be especially important," she said. "It's important for physicians to address it and encourage women to be screened."
According to Cohen, the screening rates for breast and cervical cancer are fairly high. About 75 percent of American women receive mammograms every year or two after the age of 40, she said, while about 85 percent of women get Pap smears to test for cervical cancer.
The screening rates for colorectal cancer are much lower, perhaps around a third of women, she said.
The new review, published in the May 1 issue of the journal Cancer, examined 32 studies looking at breast cancer , cervical cancer and colorectal cancer . The studies typically defined obese women as those having a body mass index [BMI, a ratio of weight to height] of 30 or above. That means they were more than merely overweight as defined by national guidelines.
Overall, obese women were 10 percent to 40 percent less likely to be screened for breast and cervical cancer compared to other women, Cohen said. Black women, however, seemed to be much less affected by obesity when it came to the screenings.
There are many theories why heavier women might be less likely to undergo health screenings, Cohen said. "It may be related to patients' emotional barriers, things like embarrassment and fear of being weighed. It may be provider-bias, physicians having a bias against obese patients. And [obese women] have other health-care needs, like dealing with high cholesterol."
Another possibility is that medical equipment may not be sized properly to accommodate larger patients, Cohen said. "None of this has been studied in any quantitative way," she added.
Dr. Massimo Cristofanilli, an associate professor in the department of breast medical oncology at the University of Texas M.D. Anderson Cancer Center in Houston, said another possibility was that "women with low-incomes choose high-caloric foods and have difficulty in being particularly careful with their lifestyle. They may also be largely uninsured and have minimal access to screening programs."
"We should recognize that prevention of obesity is a critical issue," Cristofanilli added. "Education about a healthy lifestyle should start at school and continue through media and in the family."
More information
To calculate your BMI, visit the U.S. National Heart, Lung, and Blood Institute.
Sex Ed Can Help Prevent Teen Pregnancy
Tue, 25 Mar 2008 03:46:57 GMTMONDAY, March 24 -- Comprehensive sex education may help reduce teen pregnancies without increasing levels of sexual intercourse or sexually transmitted diseases.
So find U.S. researchers who reviewed data from a 2002 national survey of more than 1,700 heterosexual teens, ages 15 to 19.
There is ongoing debate about whether abstinence-only education or comprehensive sex education is best for students.
Study lead author Pamela Kohler, a program manager at the University of Washington in Seattle, and colleagues found that about 25 percent of teens received abstinence-only education and about two-thirds received comprehensive sex education. About 9 percent -- particularly teens from poor families and those in rural areas -- received no sex education at all.
The researchers found that teens who received comprehensive sex education were 60 percent less likely to get pregnant or to get someone pregnant than those who received no sex education.
Other results -- not statistically significant, however -- suggested that comprehensive sex education, but not abstinence-based sex education, slightly reduced the likelihood of teens having vaginal intercourse. Neither approach seemed to reduce the likelihood of reported cases of sexually transmitted diseases.
The findings, published in the April issue of the Journal of Adolescent Health, support comprehensive sex education, Kohler concluded.
"There was no evidence to suggest that abstinence-only education decreased the likelihood of ever having sex or getting pregnant," she said in a prepared statement.
This study offers "further compelling evidence" about the value of comprehensive sex education and the "ineffectiveness" of the abstinence-only approach, said Don Operario, a sex education expert and professor at Oxford University in England.
More information
The Nemours Foundation has more about teen sexual health.
Free Drug Samples Hike OutofPocket Costs
Tue, 25 Mar 2008 03:47:02 GMTBy Steven Reinberg
HealthDay Reporter
MONDAY, March 24 -- Patients who receive free drug samples from their doctors end up having significantly higher out-of-pocket costs for their prescription drugs than people who don't receive free samples, a new study finds.
In fact, patients who received free samples spent about $166 in out-of-pocket costs on prescription drugs in the six months before receiving the samples, $244 for the six months in which they received samples, and $212 for the six months following receipt of the free drugs, the study found.
But patients who didn't get free samples spent about $178 on prescription drugs over six months.
"This is a curious finding because one would think, intuitively, that if you receive a free sample, one's out-of-pocket prescription cost would be lower, not higher," said lead researcher Dr. G. Caleb Alexander, an assistant professor of medicine at the University of Chicago Medical Center.
There are several possible explanations for the finding, Alexander said. One is that patients who receive free samples may be sicker than patients who don't get samples.
"The second possibility is that patients who receive free samples may go on to receive and fill prescriptions for the very same medicine that were initially begun as free samples," Alexander said. "We know that drugs that are available as free samples are those that are being widely marketed and promoted and these drugs are more expensive than their older, less promoted counterparts."
The study findings are published in the March 24 issue of the journal Medical Care.
For the study, Alexander's team collected data on 5,709 patients who had participated in the Medical Expenditure Panel Survey. The survey was done by the U.S. Agency for Healthcare Research and Quality and the patients were followed for up to two years.
Seventy-six percent of the patients had private health insurance. During the study period, 14 percent of them were given at least one drug sample. A total of 2,343 samples were distributed during the period, the researchers found.
Patients who received free samples were more likely to be younger and have private insurance, while patients with Medicaid were less likely to receive samples, the researchers noted.
The findings follow earlier research, reported in the February issue of the American Journal of Public Health, in which Harvard University researchers showed that more than 80 percent of free drug samples were given to wealthy and insured patients, not to uninsured and poorer patients.
Alexander said there are many ways doctors and patients can work together to reduce drug costs, but giving away free samples may not be the best one.
"Doctors and patients both should be encouraged to consider alternative ways to reduce patients' out-of-pocket costs," he said. "There are many other strategies doctors can use, such as prescribing a three-month rather than a one-month supply, such as using greater numbers of generic medicines, and discontinuing non-essential medicines."
Dr. David Katz, director of the Yale University School of Medicine's Prevention Research Center, said free samples aren't designed to help lower drug costs, but rather to sell newer and more expensive drugs.
"Almost every clinician's office is stocked with drug samples," he said. "For patients and providers alike, these free drugs can take on the aura of Halloween goodies. Passing them out feels like giving a gift."
But, Katz added, "free samples are by no means a long-term solution to high prescription drug costs. Rather, they are at least, in part, a marketing device, a chance to sample the wares."
The pharmaceutical industry had this to say: "Free pharmaceutical samples are beneficial to patients of all income levels. Patients are able to try out a new therapy - gaining valuable first-hand experience of its benefits and side effects - without making a co-payment," said Pharmaceutical Research and Manufacturers of America senior vice president Ken Johnson.
"What's more, contrary to statements made by critics, America's physicians prescribe medicines based on a wide range of factors, not simply receipt of free prescription drug samples," Johnson added in a prepared statement.
More information
For more on prescription drug trends, visit the Kaiser Family Foundation.
Health Tip Sports Safety for Kids
Tue, 25 Mar 2008 03:47:05 GMT- Kids need to take special care to prevent injuries to growing bones and muscles while playing sports.
Here are safety guidelines for kids, courtesy of the American Academy of Orthopaedic Surgeons:
- Prepare for sports by getting into good physical shape.
- Learn all the rules of the sport.
- Always wear appropriate protective equipment, and learn how to use it correctly.
- Always warm up and stretch before you play.
- If you feel pain or you are too tired, avoid playing until you feel better.
Therapeutic Cloning Works in Mice With Parkinson39s
Tue, 25 Mar 2008 03:46:58 GMTBy Alan Mozes
HealthDay Reporter
MONDAY, March 24 -- Therapeutic cloning successfully treated Parkinson's disease in mice, researchers report.
Using the process to develop dopamine-producing neurons with an identical genetic profile to each mouse being treated allowed scientists to significantly improve the neurological performance of the diseased animals, without provoking any evidence of immune system rejection.
"This is the first time that anyone has done this kind of cloning experiment to show the therapeutic aspect of the process in this customized way," said study author Dr. Viviane Tabar, an associate professor of neurosurgery in the department of neurosurgery at the Memorial Sloan-Kettering Cancer Center in New York City.
The finding -- which has not yet been replicated in human trials -- was published in the March 23 online issue of Nature Medicine.
Parkinson's is a neurodegenerative disorder that severely impairs motor skills and speech. According to the National Parkinson Foundation, 1.5 million Americans suffer from the disease, and men and women over 65 are at the greatest risk of developing the debilitating condition.
The illness is sparked by the breakdown of nerve cells in the brain and a resulting drop in the production of the dopamine -- a chemical key to the proper function of muscles and movement. In recent years, the effort to slow or halt dopamine loss has focused on the promise of therapeutic cloning.
Controversy over the ethical ramifications of cloning has led many researchers to draw a clear distinction between therapeutic cloning and reproductive cloning.
Both processes begin with the removal of the nucleus from a single cell taken from any part of the body of a living adult organism. In the laboratory, this isolated nucleus is then inserted into an egg cell that has been stripped of its own nucleus. This egg cell is then stimulated to grow and divide into an increasing number of cells that are all an identical genetic match to those of the original host.
At that point, the two procedures part company. On the one hand, reproductive cloning continues the cell division process to the birth of a whole new organism possessing the exact same DNA as the host. In the absence of any human reproductive cloning to date, the 1996 birth of Dolly the sheep -- the first animal ever to be cloned -- is perhaps the most famous example of this process.
Therapeutic cloning is limited to the generation of a very early-stage embryo comprised of a small collection of undifferentiated stem cells. These malleable cells are then stimulated to develop into specified cells that could be reintroduced into the body of the original host to treat any number of diseases. Such an approach circumvents a patient's natural immune response.
Tabar and her Sloan-Kettering colleague Lorenz Studer joined researchers at the RIKEN Center for Developmental Biology in Kobe, Japan, to test the viability of therapeutic cloning in mice that had been induced to develop Parkinson's.
The research team extracted cells from the tail tips of each of 24 young mice and therapeutically cloned 187 distinct stem cell lines --including at least one DNA-specific line per mouse.
After inducing the stem cells to develop into dopamine neurons, each Parkinson's mouse was "treated" with the insertion of only those neurons derived from its own cells.
Subsequent behavioral tests revealed that this one-to-one therapeutic cloning technique significantly improved the neurological function of the mice without any adverse immune response. The observed improvement was found to be much better than that achieved by a group of control mice that were given dopamine cells cloned from a single mouse line, as in prior studies.
Compared with the one-to-one treated mice, the non-matched mice had poorer immune responses, poorer motor control improvements, and a mild degree of inflammation.
"It had been thought that this process would be way too cumbersome to carry out," said Tabar. "But this validates that it is feasible and superior to using non-matched genetic material."
Michael Jakowec, an assistant professor of neurology with the George and MaryLou Boone Parkinson's Disease and Movement Disorders Research Center at the University of Southern California Keck School of Medicine in Los Angeles, cautioned that the leap to humans might be "gigantic."
"You see a lot of failures in studies that try to translate success from rodents to humans," Jakowec said. "So, it may be premature to take this to human trial just yet. Perhaps it should first be replicated in primates. But it certainly does open up a new avenue of therapeutic strategy, which may ultimately benefit patients down the road."
More information
For more on Parkinson's treatment options, visit the National Parkinson Foundation.
Many Phase 3 Cancer Drug Trials Yield Effective Medicines
Tue, 25 Mar 2008 03:46:52 GMTMONDAY, March 24 -- From 25 percent to 50 percent of new cancer treatments tested in phase 3 randomized clinical trials are eventually found to be effective, say American researchers who analyzed data from 624 phase 3 trials involving more than 216,000 patients.
The trials were all conducted by U.S. National Cancer Institute-funded cooperative groups since 1955.
Dr. Benjamin Djulbegovic, of the H. Lee Moffitt Cancer Center and Research Institute at the University of South Florida in Tampa, and colleagues found that 30 percent of the trials had statistically significant results.
In 80 percent of those trials, new treatments were found to be superior to established treatments. The risk-benefit ratio favored new treatments in 41 percent of comparisons, and favored standard treatments in 59 percent of comparisons.
"The real effects of new treatments compared with standard treatments in terms of patient outcomes such as survival is best measured by quantitative pooling of data," the study authors wrote. "When done this way, new treatments are, on average, found to be slightly superior to standard treatments, with a five percent relative reduction in the death rate. This, of course, should not be understood as the average effects of new discoveries being equally spread among all patients."
The researchers also found that breakthrough therapies were discovered in 15 percent of the trials and, in two percent of cases, the breakthroughs reduced the death rate by more than 50 percent.
The study was published in the March 24 issue of the journal Archives of Internal Medicine. Two of the study co-authors received consulting fees and grant support from drug makers Sanofi-Aventis, AMGEN, and Eli Lilly and Company.
"In conclusion, society has received a good return on its investment in the cooperative oncology group system," which funds the trials, the study authors wrote. "The public can expect that about 25 percent to 50 percent of new cancer treatments that reach the stage of assessment in clinical trials will prove to be successful. This pattern of successes has become more consistent over time. However, our results also indicate that the absolute number of discoveries might be improved if the proportion of inconclusive trials is reduced."
Cancer is the second leading cause of death in the United States. Over the years, there have been continuous improvements made in survival and other outcomes, in large part due to the introduction of new treatments tested in clinical trials, according to background information in the study.
More information
The U.S. National Cancer Institute has more about cancer clinical trials.
