A Japanese pharmaceutical company said Monday it will begin therapeutic testing of a drug it hopes will slow the decline in quality of life for some people with Down's syndrome.

The firm will trial its "Aricept" donepezil hydrochloride drug, commonly used to treat some of the symptoms of Alzheimer's disease, on people between the ages of 15 and 39 who have Down's syndrome.

Australian researchers said Tuesday they were closing in on a potential vaccine against malaria, with a study showing their treatment had protected mice against several strains of the disease.

Michael Good, from Queensland's Griffith University, said the vaccine led to naturally existing white blood cells, or T-cells, attacking the potentially deadly malaria parasite which lives in red blood cells.

New potentially life-saving HIV drugs are "beyond reach" due to restrictive patents, Doctors Without Borders (MSF) said Tuesday, even though basic medication for the disease has become cheaper.

The international medical humanitarian organisation said it was good news that the price of drugs used as first- and second-line treatments had fallen by 19 and 28 percent respectively since last year.

Virologists are casting a worried eye on this year's Islamic hajj pilgrimage to Saudi Arabia as they struggle with the enigmatic, deadly virus known as MERS which is striking hardest in the kingdom.

Little is known about the new pathogen, beyond the fact that it can be lethal by causing respiratory problems, pneumonia and kidney failure. It can be transmitted between humans, but unlike its cousin, the SARS virus, which sparked a scare a decade ago, it does not seem very contagious.

Mothers and fathers aren't the only ones urging adult children to visit their parents. China's lawbooks are now issuing the same imperative.

New wording in the law requiring people to visit or keep in touch with their elderly parents or risk being sued came into force Monday, as China faces increasing difficulty in caring for its aging population.

U.N. health officials are urging Asian governments to get rid of what they say are punitive laws that hinder the battle against HIV and AIDS by discriminating against high-risk groups and deterring them from seeking treatment.

Steven Kraus, the UNAIDS director for Asia and the Pacific, said laws that punish same-sex activities and impose harsh drug sentences have prompted a rise in new transmissions in parts of Asia.

Despite economic crises and dwindling aid, the U.N. said Monday huge progress had been made towards meeting the so-called Millennium Development Goals, including its bid to slash world hunger in half between 1990 and 2015.

"Given reinvigorated efforts, the target of halving the percentage of people suffering from hunger by 2015 appears within reach," said a U.N. progress report on its eight Millennium goals.

Two genes that are resistant to fungal wheat disease may help ward off a growing epidemic of stem rust that threatens crops in Africa, the Middle East and beyond, researchers said Friday.

International scientists have spent years trying to pin down the sections of the wheat genome that are resistant to Ug99, a pathogen that was first found to be killing wheat crops in Uganda in the late 1990s and has since appeared in Kenya, Ethiopia, Sudan, Yemen and Iran.

Britain took a step closer on Friday to becoming the first country to allow radical treatment that uses DNA from three parents to create an embryo.

The government backed an IVF-based technique designed to avoid serious mitochondrial diseases inherited on the maternal side, such as muscular dystrophy and cardiac problems.

Malawi is distributing free AIDS drugs to half a million people after years of nationwide HIV tests by the poor southern African nation, President Joyce Banda said Friday.

"Half of the population has so far been tested for HIV and half a million people are now on free drugs," Banda was quoted by state television as telling the first meeting of the UNAIDS and Lancet Commission in the administrative capital Lilongwe.