Here are some of the latest health and medical news developments, compiled by the editors of HealthDay:
Teens Opting for Real Pot
While U.S. teens are staying away from synthetic marijuana, they're smoking more of the natural version, a new survey of more than 40,000 students shows.
USA Today reported Wednesday that high school seniors who said they smoked synthetic drugs such as K2 and Spice dropped from 11 percent in 2012 to 8 percent in 2013.
However, one in 15 seniors reported smoking marijuana daily in 2013, a sharp increase from only one in 50 reporting daily use two decades ago.
The survey, supported by the U.S. National Institute on Drug Abuse and conducted by University of Michigan researchers, included students in grades 8, 10 and 12.
The investigators also found that fewer teens see marijuana as risky -- from 75 percent nearly 20 years ago to 44 percent last year and 40 percent this year, USA Today reported. When marijuana use is perceived as safe, its usage tends to increase, a study researcher noted.
About one-fourth of seniors said they'd smoked pot in the previous month, the report indicated. Meanwhile, 36 percent of seniors, 30 percent of sophomores and 12 percent of 8th graders reported smoking marijuana in the past year.
"Young people are getting the wrong message from the medical marijuana and legalization campaigns. If it's continued to be talked about as a benign substance that has no ill effects, we're doing a great disservice to young people in giving them that message," Gil Kerlikowske, director of National Drug Control Policy, told USA Today.
New Mosquito-Borne Virus in Caribbean: CDC
A travel advisory for Americans going to St. Martin has been issued after the Caribbean island reported the first cases in this part of the world of a mosquito-borne virus called chikungunya, the U.S. Centers for Disease Control and Prevention said Wednesday.
There have been 10 confirmed human cases on the French side of St. Martin and testing to confirm other cases is ongoing. Outbreaks of chikungunya have occurred in some parts of Africa, Europe, Asia and the Pacific, but this is the first time that the disease has been reported among non-travelers in the Western Hemisphere, the CDC said.
This suggests that the virus is now present in populations of mosquitoes on St. Martin and is being spread locally. It's possible that the virus will spread to other Caribbean islands and to surrounding mainland areas in coming months and years. The mosquitoes that transmit the virus are also found in some areas of the United States, the CDC said.
Infection with the chikungunya virus -- which cannot be spread from person to person -- is rarely fatal but it can cause severe and debilitating joint pain. There is no vaccine for the virus and no specific treatment for the infection. Patients recover in about a week, but some have long-term joint pain. Once a person has been infected, they're believed to have lifelong immunity to the virus, according to the CDC.
Chinese Woman Killed by Bird Flu Strain New to Humans
A Chinese woman has died from a bird flu strain that has never before affected humans, and the World Health Organization called the case "worrisome."
The 73-year-old woman in the city of Nanchang was infected with the H10N8 bird flu virus and died Dec. 6, health officials said. They added that she had been in contact with live poultry and had underlying health problems that weakened her immunity, the Associated Press reported.
The H10N8 virus has not previously been found in people. WHO and Chinese officials are working to learn more about the virus, according to Timothy O'Leary, spokesman for the WHO's regional office in Manila.
He said the source of the virus in this case remains unknown, but birds are known to carry it and it wouldn't be surprising if there is another case of a person infected with H10N8.
"It's worrisome any time a disease jumps the species barrier from animals to humans. That said, the case is under investigation and there's no evidence of human-to-human transmission yet," O'Leary told the AP.
This is the second new bird flu strain to appear in humans this year in China. An outbreak of H7N9 bird flu that began in late March infected 140 people and killed 45.
Pesticides Tied to Bee Deaths May Also Harm Humans: EU Officials
A newer class of pesticides linked to the deaths of large numbers of honey bees might also pose a threat to human health and should be more tightly controlled, European Union food regulators say.
They recommended that the European Commission further restrict the use of nicotine-derived neonicotinoids. Earlier this year, the commission temporarily banned the use of some of these pesticides on many flowering crops in Europe that attract honey bees, The New York Times reported.
The food regulators now say these pesticides may affect the developing nervous system of children, and were safe to use only in smaller amounts than currently allowed.
One of the most popular of this class of pesticides is called imidacloprid, which was developed by Bayer and is the active ingredient in products such as Bayer Advanced Fruit, Citrus & Vegetable Insect Control. It can be bought at stores in many countries, including Home Depot in the United States, The Times reported.
Colorado Meat Company Expands Recall
A Colorado meat company is expanding a recall of meat and poultry products that were produced in unsanitary conditions that included rodent activity, the U.S. Department of Agriculture said Monday.
The products in the expanded recall have the establishment number "Est. 20309" inside the USDA Mark of Inspection and include "Old Style Sausage" brand smoked Kielbasa sausage, "Old Style Sausage" brand smoked andouille sausage and "Corner Post Meats" brand hams and bacon, the Associated Press reported.
All of the recalled products from Yauk's Specialty Meats in Windsor are in retail-ready packages of various sizes and were produced between April 1, 2013 and Dec. 5, 2013. They were sold in Colorado, Nebraska, New Mexico, Utah and Wyoming.
No illnesses have been reported and the USDA's investigation is continuing, the AP said.
Doctors Keep Man's Severed Hand Alive by Attaching it to Ankle
A man's severed hand was saved by grafting it to his ankle, Chinese doctors say.
It wasn't possible to reattach Xiao Wei's right hand to his arm immediately after he lost the hand in a work accident. Instead, doctors kept the hand alive by stitching it onto Wei's left ankle and using arteries in the leg to supply the hand with blood, BBC News reported.
A month later, the hand was removed from the ankle and reattached to the arm. Wei will have to undergo several more operations but doctors say they're hopeful that he will regain full function of his hand.
"His injury was severe. Besides ripping injuries, his arm was also flattened," the surgeons said, BBC News reported. "We had to clear and treat his injuries before taking on the hand reattachment surgery."