A large team of Chinese health workers arrived in Liberia to boost the Ebola fight as a US-based doctor infected in Sierra Leone was described as being "extremely ill".

The 160-strong Chinese deployment to the west African country worst hit by the virus came as the world's most powerful economies vowed to "extinguish" the epidemic, which has claimed more than 5,100 lives.

It should be every child's dream: with the sun blazing on a sweltering afternoon exams are off, lessons have been cancelled and school's out for the summer -- and possibly the rest of the year.

But the opposite is true for Ebola-hit Liberia's children, so bored after months of school closures that they actually visit their teacherless classrooms every day to meet friends.

India's new government has launched a drive to promote the country's ancient therapies as it seeks to cash in on the multi-billion dollar global market for holistic medicine.

India claims to have natural remedies for everything from cancer to the common cold, but ministers say it has failed to capitalise on its traditions as the world has woken up to alternative medicine.

Tainted drugs apparently killed 13 women who underwent sterilization procedures in central India after autopsies ruled out any surgery faults, officials said Saturday.

Amar Agarwal, Chhattisgarh state's health minister, said a preliminary finding suggested that a poisonous chemical compound, zinc phosphate, got mixed with the drugs at the manufacturing firm whose owner has been arrested. Government laboratories are expected to give a final report by Monday.

Senegal has reopened air and sea borders with Guinea, Liberia and Sierra Leone, the countries worst hit by the Ebola virus.

The frontiers had been closed since August 21, but the restriction was lifted with immediate effect, Senegalese Interior Minister Abdoulaye Daouda Diallo said Friday.

Fast-food restaurants in the United States are "disproportionately" targeting black children and kids in middle-income and rural areas, according to a newly published study.

Researchers at Arizona State University and University of Illinois at Chicago looked at 6,716 fast-food outlets nationwide to check the extent of indoor and outdoor marketing aimed at youngsters.

Obesity among workers in the United States is costing the nation $8.65 billion a year in lost productivity, according to a study released Friday.

The study by Yale University researchers is the first to give state-level estimates of the cost of worker absenteeism due to obesity.

More than one in five U.S. high school students smoke, putting themselves at risk of disease and premature death, health authorities said Thursday.

The smoking rate of 23 percent among U.S. adolescents is higher than in the adult population, of whom 18.1 percent smoke, according to the Centers for Disease Control and Prevention.

Sierra Leone's Ebola burial boys wrap the highly-infectious body and present it to the family for dignified last goodbyes before it is taken gently away.

Removal of the dead is a necessarily traumatic experience for those left behind, but the process is a far cry from the way things used to be done.

India has defended a state-run program that offers poor women cash incentives to get sterilized after the deaths of 13 women triggered international condemnation.

Health Minister Jagat Prakash Nadda said it was a "misconception" that India set sterilization targets for local authorities in an effort to control the growth of its billion-plus population.