A new contamination scare hit New Zealand's multi-billion dollar dairy industry on Monday after it was revealed a milk product with excessive nitrate levels had been exported to China.

Both New Zealand's Ministry of Primary Industries (MPI) and the company at the centre of the latest scare, Westlake Milk, insisted the product called lactoferrin did not pose a safety risk.

Young Australians have a reputation for being fit and enjoying a sporty, outdoorsy lifestyle, but research released Monday found they are stacking on more weight than any other age group.

The alarming findings of the Australian Diabetes, Obesity and Lifestyle Study have raised concerns that by putting on so much weight in their 20s and 30s, Australians are at more risk of developing diabetes in middle age.

The British government said Thursday it would lift a ban on staff with HIV working in the state-run National Health Service from carrying out certain procedures on patients.

Staff who are undergoing treatment for HIV will be able to carry out all procedures from which they are currently banned, including surgery and dentistry, provided they are having effective anti-retroviral drug therapy.

Nepal's government on Thursday ordered health workers to cull half a million chickens to combat a major bird flu outbreak on the outskirts of the capital Kathmandu.

The orders come after tens of thousands of birds have already been killed in what government officials describe as one of the Himalayan nation's worst outbreaks of avian flu.

Aid workers in war-torn Somalia are struggling to contain a dangerous outbreak of the crippling polio virus, with rampant insecurity hampering efforts, the United Nations said Friday.

Six years after the Horn of Africa nation was declared free of the virus, at least 105 cases have been confirmed in Somalia, the "worst outbreak in the world in a non-endemic country," the U.N. Office for the Coordination of Humanitarian Affairs said in a statement.

Adult obesity in the U.S. still isn't budging, the latest government survey shows.

The national telephone survey found 13 states with very high rates of obesity last year. Overall, the proportion of U.S. adults deemed obese has been about the same for years now.

When people have a brain injury so severe that they can't squeeze a loved one's hand or otherwise respond, there are few good ways to tell if they have any lingering awareness or are in a vegetative state. Now researchers have created a tool to peek inside the brain and measure varying levels of consciousness.

The work reported Wednesday is highly experimental, not ready for bedside use yet — and if it pans out, a big question is how to use it without raising false hope. No one knows what level of consciousness at a certain point after injury really predicts recovery.

Long-term results from a major U.S. study ease worries about the safety of a hormone-blocking drug that can lower a man's chances of developing prostate cancer.

The drug cut prostate cancer risk by 30 percent without raising the risk of dying of an aggressive form of the disease as earlier results hinted it might.

Faced with falling sales of its diet soda, Coca-Cola is running ads in the United States that say its sugar-free beverages, sweetened with the chemical aspartame, are safe.

The print ads, which began appearing Wednesday in major U.S. newspapers, show a pair of laughing women, one holding a bottle of diet Coke in hand, alongside text that reads: "Quality products you can always feel good about."

People who use Facebook may feel more connected, but less happy.

A study of young adults released Wednesday concluded that the more people used Facebook, the worse they subsequently felt.