Here are some of the latest health and medical news developments, compiled by editors of HealthDay:
Panel: USDA Misled Public About Mad Cow
A Congressional committee has called the credibility of the U.S. Department of Agriculture into question over a key fact in the nation's first case of mad cow disease.
When the USDA announced the case in December, the agency said that the cow was a "downer" when it was slaughtered, meaning that it could no longer walk. But a month-long inquiry by the House Committee on Government Reform found three eyewitnesses to the slaughter who testified that the cow was not a "downer" and didn't appear to be sick at all, according to the Washington Post.
The rebuke was bipartisan, the paper reports. Thomas M. Davis III (R-Va.), the committee's chairman, and its ranking Democrat, Rep. Henry A. Waxman (Calif.), sent a letter to Agriculture Secretary Ann Veneman, warning that this information "could have serious implications for both the adequacy of the national [mad cow] surveillance system and the credibility of the USDA."
The Post quotes committee spokesman David Marin as saying that if it's true the only infected cow was able to walk, "then clearly it's not safe to assume that all infected cattle will be downers."
USDA spokeswoman Julie Quick told the paper that the department wouldn't comment on the letter, but that the agency wanted to get to the bottom of the issue.
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Flu Shot to Change Next Year
Two of the three strains of virus in next year's flu vaccine will be replaced, and will include one that is responsible for the outbreak of influenza this season.
Experts at the World Health Organization recommended the changes last week, and the U.S. Food and Drug Administration is expected to adopt them on Thursday, the New York Times reports.
Decisions about flu vaccine for the following year must be made many months in advance because of the time it takes to prepare it. Each vaccine has three strains, according to the Times account.
The new vaccine will include the Fujian strain that has infected people in the United States and Europe this winter. When the decision to develop this season's vaccine was made, experts knew that the strain was circulating but didn't have enough time or information to include it, the Times reports.
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Scan May Improve Brain Cancer Therapy
A new type of brain scan will allow doctors to determine at a much faster pace whether tumors are responding to chemotherapy.
The BBC reports that the technology, called nuclear magnetic resonance, enabled cancer specialists to predict weeks earlier than what is currently possible whether the tumors, called gliomas, were being destroyed by the drug temozolmide.
Currently, doctors learn whether the treatment is effective months after it is started. With the scan, they can detect subtle changes in the tumor. If they find the drug isn't working, they can change to another, the BBC reports.
"We were able to identify chemical changes using the machine which were early indicators that the drug was working," the study's lead researcher, Dr. Andrzej Dzik-Jurasz of the Institute of Cancer Research, told the network.
The results appear in the British Journal of Cancer.
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Asian Bird Flu Claims 2 More Lives
The human death toll from bird flu rose to 22 Wednesday when two young children, one each from Vietnam and Thailand, were added to the count.
Both victims from the only two nations reporting human cases were 4-year-old boys , the Associated Press reports. Fifteen deaths have been counted so far in Vietnam and seven in Thailand.
Ten Asian nations have reported outbreaks of the deadly virus among fowl, and at least 80 million birds have been ordered slaughtered, the wire service says. Fearful of the disease's spread, virus-free Singapore slaughtered 5,000 healthy chickens Wednesday in a practice cull.
The United Nations Food and Agriculture Organization says it will hold an emergency meeting Feb. 26-28 in Bangkok to discuss common ways to fight the disease, the AP reports.
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Elderly Drivers Have Greater Accident Risk: Study
A new AAA-sponsored study appears to confirm a common perception that elderly drivers are more likely to die in car crashes than younger drivers.
Drivers over 85 were nearly four times as likely to be involved in a fatal accident than middle-aged drivers, the Associated Press reports of the study released Wednesday. As expected, older drivers were increasingly likely to have impaired judgment and reflexes, and were more likely to die once involved in an accident due to their frail physical conditions, the survey found.
While not suggesting any new mandatory regulations, AAA recommends that seniors consider taking driving refresher courses. Some 35 states offer insurance discounts for people who take such courses, the AP reports.
AAA says cars can be modified with larger mirrors and brighter dashboard displays to help older drivers. An agency spokeswoman also recommends better lighting and signs at intersections, and protected left-hand turn lanes.
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One-Fifth of American Adults Have Tried Low-Carb Diets
Twenty percent of American adults say they've tried a low-carbohydrate diet in the past two years, a new poll finds.
Eleven percent of American adults -- 24 million of them -- are currently on anti-carb regimens, according to the survey of 1,800 people by Massachusetts-based Opinion Dynamics Corp. And 19 percent of respondents who aren't on low-carb fare say they are "very" or "somewhat" likely to try such a diet in the next two years, the polltakers say in a prepared statement.
A recent downturn in American orange juice consumption seems almost entirely attributable to a greater-than-expected adoption of low-carb diets, the survey company's statement adds.
Two-thirds of respondents on these regimens say they rely "very much" or "somewhat" on low-carb brand labels and advertising when making purchasing decisions, the poll also finds.
