The devastating effect of Alzheimer's disease on bilingual people has been thrown into focus in Canada, where the sudden loss of a second language can leave sufferers feeling like strangers in their own country.

Despite increasing evidence that bilingualism can actually delay the onset of dementia, those grappling with the ravages of the disease often find themselves isolated by the lack of essential services in their language of choice.

The hunt for an HIV vaccine has gobbled up $8 billion in the past decade, and the failure of the most recent efficacy trial has delivered yet another setback to 26 years of efforts.

With the next attempts expected to be years away, top researchers now say there is a "void" or a "gap" in current clinical trial efforts to test whether a vaccine may be safe and effective in people.

Aid organisation Oxfam warned on Monday that the warmer weather will increase health-related risks for hundreds of thousands of Syrian refugees in Jordan and Lebanon, and appealed for urgent funds.

With temperatures set to soar up to 40 degrees Celsius (104 Fahrenheit), and as refugees continue to flee to Jordan and Lebanon, "the health risks must be urgently addressed," Oxfam said in a statement.

China's human H7N9 bird flu outbreak has cost the country's poultry industry more than 400 billion yuan ($65 billion) as consumers shun chicken, government officials said according to state media Monday.

The sector has been losing an average of one billion yuan a day since the end of March, the Beijing Times said, citing Li Xirong, head of the National Animal Husbandry Service.

Lawyers for the founder of French firm PIP whose faulty breast implants sparked a global health scare denied wrongdoing Friday as the court said it would deliver a verdict in December.

In closing arguments, the defence called for a lighter sentence than the four-years imprisonment requested by prosecutors.

Europe's medicines watchdog said Friday the benefits of acne drug Diane-35, also widely used as a contraceptive, outweigh the risk of developing blood clots in the veins -- when correctly prescribed.

The clot risk was "low", said a European Medicines Agency (EMA) ruling on a French-initiated review of the drug's safety.

A new case of the deadly coronavirus has been detected in Saudi Arabia where 15 people have already died after contracting it, the health ministry announced on Saturday on its Internet website.

"One new case of novel coronavirus recorded in the Eastern Region" where most of the kingdom's cases have been registered, said the ministry, which this week created a special web page dedicated to the outbreak.

A Nigerian court on Friday sentenced two officials from a pharmaceutical company to seven years in prison over the sale of an adulterated teething drug which killed 84 babies in 2008.

Children between two months and seven years-old, died from renal failure after taking the painkiller which was found to contain high levels of diethylene glycol, a poisonous solvent mostly used in brake fluid and as an engine coolant.

Big names in medicine are set to give an upbeat assessment of the war on AIDS on Tuesday, 30 years after French researchers identified the virus that causes the disease.

Scientists will pay tribute to the astonishing success of AIDS drugs and highlight steps being taken towards a cure -- a goal once deemed all but out of reach.

The World Health Organization says a yellow fever booster vaccination given 10 years after the initial shot isn't necessary.

The U.N.'s global health agency said Friday that its expert group on immunization believes a single dose of vaccination is sufficient to confer lifelong immunity against the disease.