Here are some of the latest health and medical news developments, compiled by editors of HealthDay:
U.S. Chief Justice to Miss Start of 2005 Court Session
Chief Justice William Rehnquist, recovering from thyroid cancer, still isn't well enough to open the U.S. Supreme Court's first session of 2005, the court said in a statement issued Friday.
"Continuing secretions caused by his tracheotomy and radiation therapy" will cause the 80-year-old chief justice to miss at least Monday's first day of arguments, the statement said. Rehnquist hasn't attended a court session since Oct. 13, according to the Bloomberg news service.
Rehnquist has undergone a tracheotomy, in addition to chemotherapy and radiation. Experts told the news service that this treatment plan is usually associated with a particularly deadly form of the disease called anaplastic cancer.
Rehnquist, the court's longest-serving justice, was appointed in 1972 and became chief justice in 1986. The nation's high court hasn't had a vacancy since 1994.
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Canada Expands Its Mad Cow Probe
Canadian officials said Friday that cattle potentially infected with mad cow disease may have been eaten by humans, but stressed the chance of contracting a potentially fatal illness is extremely low.
The officials also said that one cow in the suspect herd on an Alberta farm may have been shipped to the United States.
CBC reported that the Canadian Food Inspection Agency was tracking 141 cattle from the farm where an 8-year-old dairy cow was confirmed on Jan. 2 to have the disease, also known as bovine spongiform encephalopathy. Some of these cows may have been made into animal or human food, said an agency spokesman, Dr. Gary Little, at a news conference in Ottawa.
"At least a small number of them have been slaughtered and have entered the human food system, potentially," Little said.
He and other officials downplayed the risk to consumers, even though BSE can cause the human disease of Creutzfeldt-Jakob that killed at least 40 people in Britain in the 1990s, CBC reported.
Little said investigators from his agency are tracking a total of 93 dairy and 48 beef cattle from the farm to see whether the animals could have been exposed. They have quarantined nine dairy cattle born on the farm a year before and a year after the infected animal was delivered in October 1996 and plan to begin killing and testing the animals for BSE next week.
The news may bolster the arguments of several U.S. politicians, who on Thursday unsuccessfully pressed the federal government to delay reopening its border on March 7 to shipments of Canadian cattle and beef.
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Another Study Links Hormone Therapy With Stroke
Use of hormone replacement therapy (HRT) by menopausal women was struck another blow Friday by a new study that showed HRT was found to increase the risk of stroke by almost one-third.
The analysis, reported in the British Medical Journal, pooled results of 28 trials involving nearly 40,000 women. The risk of ischemic stroke, caused by an insufficient supply of blood to the brain, rose by 29 percent in women on HRT, according to an account in the Times of London. Fatal or disabling strokes of all types rose by 56 percent among these women, the newspaper said.
The trials analyzed included a 2002 U.S. Women's Health Initiative study that linked HRT to an increased risk of breast cancer, heart attack, stroke and life-threatening blood clots. That trial, involving some 17,000 women over age 50, found that HRT use boosted participants' risk of stroke by 41 percent, the Times reported.
Researchers who conducted the fresh review from Britain's University of Nottingham advised that patients at higher risk of stroke should stop taking HRT unless there was a strong medical need to do so.
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Age Weighs Heavily on Success of In Vitro Fertilization
A woman's age plays a major role in the success of infertility treatments, including in vitro fertilization, according to a new study by the U.S. Centers for Disease Control and Prevention.
The younger a woman is when assisted reproductive technology (ART) is used, the more likely she is to give birth using her own eggs, the agency said in a statement released Friday. Success rates declined rapidly once a woman reached her mid-30s, the statement added.
Among study participants, 37 percent of ART procedures done in women younger than 35 resulted in live births. This percentage fell to 31 percent among women 35 to 37, to 21 percent among women 38 to 40, to 11 percent among those 41 to 42, and to 4 percent among women older than 42.
ART includes infertility procedures in which both egg and sperm are manipulated in a laboratory, the CDC said, noting that the majority involve in vitro fertilization.
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CDC Warns of Disease Risk Among People With Pet Rats
People who keep rats as pets or handle them in medical labs could contract a potentially fatal disease called rat-bite fever, the U.S. Centers for Disease Control and Prevention said Friday.
The agency issued the warning in its Morbidity and Mortality Weekly Report after investigating two deaths from the rare illness that occurred in 2003. The first person, a 19-year-old Washington state woman, had kept nine rats as pets but had no known animal bites. The second fatality involved a 52-year-old Florida pet store employee who had been bitten on her right index finger.
Both patients died within 12 hours of being hospitalized with symptoms including headache, abdominal pain, diarrhea, extremity pain and fatigue.
Rat-bite fever is caused by Streptobacillus moniliformis, a bacterium carried in rats' upper-respiratory tract. The agency said human infection could result from a bite or scratch, merely handling an infected animal, or ingestion of contaminated food or water.
The agency said people who handle rats should take precautions that include wearing gloves, regular hand washing, and avoiding hand-to-mouth contact when handling rats or cleaning their cages.
