A closely-watched prototype therapy to inject corrective genes into the brain to treat Parkinson's disease has cleared an important safety hurdle, doctors said Friday.

Tested on 15 volunteers with an advanced form of the degenerative nerve disease, the technique proved safe and the results were encouraging, they said.

Teenage shoe-shiner Amit contracted polio as a toddler, leaving him with damaged legs and a twisted spine. He has never seen a doctor and the country's eradication of the disease came too late for him.

On Monday, India will mark three years since its last polio case, leaving it on the cusp of being declared free of the ancient scourge in what is arguably its, and one of the world's, biggest health success stories.

Japan's health ministry said Friday it was probing claims falsified data was used in an Alzheimer's disease study involving major pharmaceutical firms, a day after filing an unrelated criminal complaint against Swiss drugs giant Novartis.

Health officials said they were questioning researchers after being told false data was used in clinical testing for the $28 million government-backed Alzheimer's study, aimed at improving diagnosis of the disease.

The French drug safety agency has approved commercial sales of a medicine derived from cannabis for the first time in France.

France's Health Ministry said in a statement Wednesday that sales of Sativex, produced by Britain's GW Pharmaceuticals, will be allowed for the treatment of muscle spasms associated with multiple sclerosis.

The intestine of an American cholera victim from the mid-1800s has yielded new clues to the evolution of the deadly bacterium and may help prevent future outbreaks, researchers said Wednesday.

Using the sample of an intestine, preserved in a jar at a Philadelphia medical museum, scientists reconstructed for the first time the genome of classical cholera, the predecessor of the modern-day strain.

Canada announced Wednesday the first H5N1 avian flu death in North America, of a patient who had just returned from China, and said it was urgently contacting airline passengers on the victim's flights.

It was also the first known instance of someone in North America contracting the illness, Canada Health Minister Rona Ambrose told a press conference, stressing it was an "isolated case."

New York governor Andrew Cuomo announced Wednesday that he will authorize the medical use of marijuana, making his the 21st U.S. state to do so and one of the biggest.

Cuomo, a Democrat who has in the past opposed such a measure, announced a limited pilot program to serve the state of 19.5 million people.

Poland's government on Tuesday unveiled a plan to fight driving under the influence, after a drunk driver killed six pedestrians on New Year's Day.

Poland has one of the worst road safety ratings in the 28-member European Union, and reckless and drunk driving are part of the problem.

More people smoke worldwide today than in 1980, as population growth surges and cigarettes gain popularity in countries such as China, India and Russia, researchers said Tuesday.

For instance, China boasted nearly 100 million more smokers in 2012 than it had three decades ago, even though its smoking rate fell from 30 to 24 percent in that span, said the findings in the Journal of the American Medical Association.

Japan's health ministry will Wednesday file a criminal complaint against the local arm of Swiss pharmaceutical giant Novartis over alleged exaggerated advertising for a popular blood-pressure drug, Kyodo News agency reported.

Novartis Pharma KK has been under fire since a university said the data in clinical studies might have been skewed to promote Valsartan.