Pakistan, the world's number-one exporter of polio, has seen a rush on vaccines and angry scenes at hospitals after new World Health Organization guidelines aimed at halting the crippling disease caused widespread confusion.

The WHO declared a "public health emergency" at the start of May after new polio cases began surfacing and spreading across borders from countries including Pakistan.

Australian researchers unveiled on Tuesday a Twitter tool to map moods around the world in real-time to help improve the allocation of mental health services.

The online tool, called "We Feel", analyses up to 32,000 tweets per minute -- about 10 percent of all English-language tweets -- for 600 words that are then linked to emotions such as love, joy, surprise, anger, sadness and fear.

A man from Saudi Arabia who is one of three patients diagnosed with an infection from a Middle East respiratory virus in the United States has been released from an Orlando, Florida, hospital.

Officials from the state health department and Dr. P. Phillips Hospital said in a news release Monday that the 44-year-old unidentified man has been discharged.

An airborne toxin that is blown into Japan from northeast China could be the cause of the mysterious Kawasaki disease, a childhood illness that mostly affects the very young, researchers said Monday.

Kawasaki disease occurs worldwide but is most common in Japan and causes fever, rash, peeling fingernails and in about 25 percent of cases it can also lead to coronary aneurysm, a life-threatening ballooning of arteries that supply the heart.

The secret to the Mediterranean diet may be in the salad.

Eating unsaturated fats, like those in olive oil, along with leafy greens and other vegetables creates a certain kind of fatty acid that lowers blood pressure, scientists said Monday.

The lives of three million women and babies can be saved every year by 2025 for an annual investment of about a dollar per head in better maternity care, researchers said Tuesday.

About 8,000 newborn babies die and another 7,000 are stillborn every day -- 2.9 million and 2.6 million per year respectively, according to a review of data from 195 countries published in The Lancet medical journal.

At least nine people have died in a cholera outbreak in war-torn South Sudan, scores of others are sick and the epidemic looks set to worsen, the World Health Organization said on Monday.

"There have been nine deaths and 138 cases so far," WHO spokesman Tarik Jasarevic told Agence France Presse in Geneva.

A court in Uganda has sentenced a nurse to three years in jail after finding her guilty of criminal negligence in a case stemming from allegations she intentionally tried to infect her patient with HIV.

The nurse, Rosemary Namubiru, maintained her innocence throughout the trial.

Saudi health authorities reported Monday new deaths from the MERS coronavirus, taking to 173 the overall number of fatalities from the disease in the world's worst-hit country.

The health ministry said on its website that five people have died, including a 28-year-old woman in the port city of Jeddah, and a 32-year-old man in northern Tabuk.

New York raised the minimum age to buy cigarettes to 21 on Sunday, in its latest initiative to encourage healthier behavior among residents.

The law, signed November 19 shortly before former mayor Michael Bloomberg finished his second term, had a six-month waiting period before it came into effect -- but its impact can already be clearly felt.