The deaths of 57 more people from Ebola in west Africa have pushed the overall fatality toll from the epidemic to 729, the World Health Organization said Thursday.

The 57 deaths were recorded between Thursday and Sunday last week in Guinea, Liberia, Nigeria and Sierra Leone, the U.N. health agency said in a statement.

Sierra Leone leader Ernest Bai Koroma declared a state of emergency on Thursday and cancelled a planned trip to the US-Africa summit as the country struggled to contain the deadly Ebola epidemic.

Japan's smoking rate has dropped below 20 percent for the first time, according to a new survey, as a recent rise in cigarette prices helped to further discourage the habit.

Drug-resistant malaria parasites are now firmly established in border regions in four Southeast Asian countries, imperiling global efforts to control the disease, experts warned on Wednesday.

The scientist who helped discover the Ebola virus said the outbreak in west Africa was unlikely to trigger a major epidemic outside the region, adding he would happily sit next to an infected person on a train.

Liberia announced Wednesday it was shutting all schools and placing "non-essential" government workers on 30 days' leave in a bid to halt the spread of the deadly Ebola epidemic raging in west Africa.

"All schools are ordered closed following further directives from the ministry of education," President Ellen Johnson Sirleaf said in a televised address to the nation.

Doctors, nurses and hospital workers fighting the Ebola epidemic in west Africa are struggling with a daily burden of exhaustion, shortage of staff and fear for themselves over the deadly virus, specialists say.

Containing an outbreak by a lethal pathogen places big demands on workers in any health system, but this is especially the case in one of the world's poorest regions, they say.

The European Union is equipped and ready to treat victims should the deadly Ebola virus, which has killed hundreds in West Africa, be found in member states, EU sources said Wednesday.

"We cannot rule out the possibility that an infected person arrives in Europe but the EU has the means to track and contain any outbreak rapidly," one EU source said.

The new chairman of the Pacific Islands Forum (PIF) said Wednesday that he was determined to change the unhealthy lifestyle choices that have made his region the fattest in the world.

Palau President Tommy Remengesau said that junk food had become a blight on Pacific island communities, leading to epidemic rates of heart disease, diabetes, and high blood pressure among an increasingly obese population.

The teenager sits quietly in a Mumbai rehab clinic, a victim of India's emerging fad for the drug crystal meth, which experts say is spurred by loopholes in the country's giant chemical industry.