In the 1950s the 3-foot-long guinea worm ravaged the bodies of an estimated 50 million people, forcing victims through months of pain while the worm exited through a swollen blister on the leg, making it impossible for them to tend to cows or harvest crops. By 1986, the number dropped to 3.5 million. Last year only 3,190 cases were reported.

Today the worm is even closer to being wiped out. Fewer than 1,700 cases have been found this year in only four countries — Ethiopia, Ghana, Mali and Sudan, where more than 95 percent of the cases are. The worm's near-eradication is thanks in large part to the efforts of Carter and his foundation.

Vanderbilt University economist Kip Viscusi studied the net costs of smoking-related spending and savings and found that for every pack of cigarettes smoked, the country reaps a net cost savings of 32 cents.

Cases of Guinea worm disease — a horrifying infection that culminates in worms coming out of a victim's skin — have reached an all-time low worldwide, former U.S. President Jimmy Carter announced Friday.

Only 4,410 cases were reported worldwide during the first ten months of this year, all in six African countries. Nearly 80 percent were in Sudan, according to The Carter Center, a nonprofit founded by Carter and his wife that helps fight disease and champions voting and human rights around the world.

That total is a dramatic drop from the 3.5 million cases in 20 nations that were reported when The Carter Center's eradication campaign began in 1986. It's also less than half the 9,585 cases reported by individual nations in 2007.

After the three months, the men had changes in activity in about 500 genes -- including 48 that were turned on and 453 genes that were turned off.

The activity of disease-preventing genes increased while a number of disease-promoting genes, including those involved in prostate cancer and breast cancer, shut down, according to the study published in the journal Proceedings of the National Academy of Sciences.

The research was led by Dr. Dean Ornish, head of the Preventive Medicine Research Institute in Sausalito, California, and a well-known author advocating lifestyle changes to improve health.

"It's an exciting finding because so often people say, 'Oh, it's all in my genes, what can I do?' Well, it turns out you may be able to do a lot," Ornish, who is also affiliated with the University of California, San Francisco, said in a telephone interview.

Of more than 2,000 doctors surveyed, 59 percent said they support legislation to establish a national health insurance program, while 32 percent said they opposed it, researchers reported in the journal Annals of Internal Medicine.

The 2002 survey found that 49 percent of physicians supported national health insurance and 40 percent opposed it.

Now researchers at Yale University have found that a virus that's in the same family as rabies effectively kills an aggressive form of human brain cancer in mice. Using time-lapse laser imaging, the team watched vesicular stomatitis virus (VSV) rapidly home in on brain tumors, selectively killing cancerous cells in its path, while leaving healthy tissue intact. What's more, Anthony Van den Pol, lead researcher and professor of neurosurgery and neurobiology at Yale, says that VSV is able to self-replicate and produce secondary lines of defense.

- A woman in her late teens died from an acute asthma attack triggered by secondhand cigarette smoke shortly after arriving at her job as a waitress in a bar in Michigan, researchers reported on Friday.

They said it was the first reported case of an immediate death caused by secondhand smoke.

In a paper published online Monday in the Public Library of Science Medicine journal, Dutch researchers found that the health costs of thin and healthy people in adulthood are more expensive than those of either fat people or smokers.

France, Japan and Australia rated best and the United States worst in new rankings focusing on preventable deaths due to treatable conditions in 19 leading industrialized nations, researchers said on Tuesday.

Coffee vs. tea: Benefits and risks

While tea lovers revel in tea?s likely health benefits, coffee drinkers worry that anything as deliciously stimulating as java must be unhealthful. But research shows that coffee is generally safe in moderate amounts and might have surprising benefits of its own: Large observational studies have linked regular coffee consumption with reduced risks of type 2 diabetes, gallstones, and possibly Parkinson?s disease. Still, both green and black tea trump coffee for protection against cancer, heart disease, and possibly osteoporosis.

Even though we still live in a sea of rabies and even though we have rabies viruses circulating among raccoons and foxes and bats, the dog rabies virus, which is the most responsible for dog-to-dog transmission and which is still the greatest burden to humans ... it is that virus that has been eliminated."

In men, caffeine consumption didn't correlate with scores on mental-performance tests. However, women reporting heavy caffeine consumption typically exhibited less of a decline during the 4-year-study in their scores on an Isaacs test. This exam challenges an individual to retrieve verbal material. For instance, participants might be asked to name all the animals they can think of in 90 seconds.

Women consuming the most caffeine were also less likely than those in other groups to suffer declines in their scores on a test of visual recall. Here, volunteers viewed a shape and later had to pick it out from a field of disparate shapes.

Drinking water is the best alternative, Perle says, but if you're not willing to make the switch, consider rinsing with it after consuming acidic foods or beverages.

Why switch to the mouth? Surgeon's answer: "Since only half the population has vaginas we were looking for a more universal platform."

Researchers on Thursday published the genome -- a map of all the DNA -- of the mosquito species Aedes aegypti, a connoisseur of human blood that spreads disease in tropical and sub-tropical locales worldwide.

People with migraines also may be suffering from some brain damage as brain cells swell and become starved of oxygen -- a finding that may help explain why migraine sufferers have a higher risk of stroke, researchers reported on Sunday.

Previous studies have linked early childhood exposure to bacteria to protection against allergies and asthma in adulthood. The new finding take this idea, called the "hygiene hypothesis," a step further, and suggests bacteria-exposure not only boosts our immune systems, but alters our vulnerability to conditions such as depression as well.

"These studies help us understand how the body communicates with the brain and why a healthy immune system is important for maintaining mental health," Lowry said. "They also leave us wondering if we shouldn�t all be spending more time playing in the dirt."

Beta carotene and vitamins A and E, antioxidant supplements taken by millions to fight disease, may actually raise the risk of death, a review of 68 studies on nearly a quarter-million people said on Tuesday.

Interesting. Aging may be a untoward result of our cancer defenses. -peaches

These results support a hypothesis Campisi has developed over the past few years. Natural selection favors anticancer proteins such as p16, but only in moderation. If these proteins become too aggressive, they can create their own threats to health by making bodies age too quickly. ?It?s still a working hypothesis,? Campisi admits, ?but the data are looking stronger and stronger.?   

Six Ways to Cope with Holiday Jet Lag

During the holiday season, many of us will find ourselves on planes, traveling to see family and friends. One unfortunate aspect of modern travel can be jet lag. So how can you get over it quickly?