The prescription drug methadone is linked to over 30 percent of painkiller overdose deaths, according to a report released by the Centers for Disease Control (CDC) and Prevention Tuesday.

"Death from opioid overdose have increased four-fold in the past decade, and methadone now accounts for nearly a third of opioid-associated deaths," said CDC Director Thomas Frieden.

An epidemic of H1N1 flu has infected almost 900 people and claimed 11 lives in Bolivia, health officials said Tuesday.

Although most of the cases occurred in the last few weeks, the outbreak does not rise to the level of a national epidemic, officials said.

An outbreak of cholera in eastern Cuba has killed at least three people, 130 years after the last known case of the disease was reported on the island.

Health workers have identified 53 people infected with the illness in the coastal town of Manzanillo.

The biggest probe yet into the inherited causes of osteoarthritis has turned up eight genes associated with this painful disease, bringing the tally of suspects to 11, The Lancet reported on Tuesday.

Researchers led by John Loughlin at Newcastle University, northeast England, compared the DNA code of more than 7,400 people with severe hip and knee osteoarthritis against that of more than 11,000 counterparts who did not have the disease.

The Mexican government declared a national animal health emergency on Monday in the face of an aggressive bird flu epidemic that has infected nearly 1.7 million poultry.

More than half the infected birds have died or been culled, the agriculture ministry said of an epidemic that was confirmed on Friday by the U.N.'s Food and Agriculture Organization (FAO).

GlaxoSmithKline was socked with $3 billion in fines by U.S. authorities Monday over charges it marketed drugs for unauthorized uses, held back safety data, and cheated the government's Medicaid program.

In a longstanding case that officials said bared the ugly underside of the U.S. pharmaceutical industry, GSK was also accused of paying kickbacks to doctors, paying for expensive trips and other benefits, to gain their support for the drugs the company was pushing.

Two-thirds of South African teens and adults suffer from a "fear of missing out" on more interesting activities than what they're doing, a study by a pharmaceutical firm showed on Monday.

Over 62 percent of some 3,000 respondents aged between 15 and 50 years said in a nationwide survey that they live in "constant fear" of missing out on something more exciting than what they are doing.

Even for infants born full-term, a little more time in the womb may matter.

The extra time results in more brain development, and a study suggests perhaps better scores on academic tests, too.

All vehicles travelling on French roads must carry a chemical or electronic breathalyzer test from Sunday, under new rules aimed at reducing alcohol-driven accidents.

"Alcohol has been the main cause of mortality on roads since 2006," according to road security authorities.

People who were hit or spanked as children face higher odds of mental ailments as adults, including mood and anxiety disorders and problems with alcohol and drug abuse, researchers said Monday.

The study, led by Canadian researchers, is the first to examine the link between psychological problems and spanking, while excluding more severe physical or sexual abuse in order to better gauge the effect of corporal punishment alone.