Men who are obese in their early 20s are twice as likely as peers of average weight to die before reaching the age of 55, a study said Tuesday.

Writing in the journal BMJ Open, a team of researchers reported on a 33-year study of 6,500 Danish men who were 22 years old in 1955.

Children born outside the United States have a lower risk of asthma, skin and food allergies, and living in the United States for a decade may raise a person's allergy risk, said a study on Monday.

The research in the Journal of the American Medical Association suggests that certain environmental exposures could trigger allergies later in life, overcoming the protective effects of microbial exposure in childhood.

The deadly H7N9 bird flu strain claimed a new victim on Monday when a hospital patient died in China, state media reported, bringing the death toll from the recently identified virus to 24.

A patient surnamed Chen died in the eastern city of Shanghai after 12 days of medical treatment failed, Xinhua news agency said. China has recorded more than 120 cases of H7N9 infection so far.

Chinese health officials say the 4-year-old son of a man infected with a new strain of bird flu has also caught the virus.

Shandong province's health department says there is no evidence of human-to-human transmission, and that the boy is in stable condition at a hospital.

They sweep. They swab. They sterilize. And still the germs persist.

In U.S. hospitals, an estimated 1 in 20 patients pick up infections they didn't have when they arrived, some caused by dangerous 'superbugs' that are hard to treat.

Gene analysis of malaria parasites has pinpointed western Cambodia as the hotspot of strains that are dangerously resistant to artesiminin, the frontline drug against the disease, scientists said on Sunday.

An international consortium of researchers unraveled the genetic code of 825 samples of the Plasmodium falciparum parasite from Burkina Faso, Gambia, Ghana, Mali, Thailand, Vietnam and from northeastern and western Cambodia.

Plastic surgery to remove fat and excess skin on the upper arms has gained appeal in the United States, where the procedure has exploded in popularity since the year 2000, experts said Monday.

More than 15,000 U.S. women had the procedure known as arm lifts, or brachioplasty, done last year, at a cost of $61 million nationwide, according to the American Society of Plastic Surgeons.

A fire that killed 36 patients at a dilapidated wooden psychiatric facility has exposed Russia's failure to move on from the old Soviet system of punitive psychiatry used against political dissidents.

Two staff and 36 patients -- apparently too sedated or disorientated to escape from their mass dormitory with barred windows -- perished in the fire that broke out on Friday.

China's deadly outbreak of H7N9 bird flu has spread to a province in the country's south, the government said Friday, marking the second announcement in two days of a case in a new location.

The local health bureau in the southeastern province of Fujian said a 65-year-old man was confirmed to have the virus.

More than 100 doctors from around the world have signed a letter decrying the high cost of cancer drugs which reach $100,000 per year or more, and calling for pharmaceutical companies to ease prices.

The United States represents the "extreme end of high prices," leading to healthcare costs that amounted in 2011 to 2.7 trillion, or 18 percent of U.S. GDP, compared to six to nine percent in Europe, the doctors wrote in the journal Blood.