More than 100 people in the central state of Indiana have tested positive for HIV in an outbreak linked to the sharing of intravenous needles, and officials said Friday they're trying to combat unfounded fears among drug users that they could be arrested if they take part in a needle-exchange program created to stem the spread of the virus.

The state's Joint Information Center said there had been 95 confirmed HIV cases and 11 preliminary positive cases tied to the outbreak as of Thursday. That's up from last week's 84 confirmed HIV cases and five preliminary positive cases.

Real progress is being made in the fight against Ebola, but the deadly outbreak in west Africa remains a major international health emergency, the World Health Organization said Friday.

The U.N. health agency said after its fifth emergency meeting on the haemorrhagic fever that the situation in the worst-hit countries of Guinea, Liberia and Sierra Leone remained a "public health emergency of international concern".

The U.N.'s World Health Organization on Friday warned that too many women in developing and wealthy countries alike are resorting unnecessarily to Caesarean sections to give birth.

Other pregnant women with a real medical need for a C-section simply do not have access to the operation, the WHO added.

Austria on Friday finally decided to ban smoking in cafes and restaurants from 2018 after years of debate in a country famed for its cafe culture.

"We have at last joined Europe in terms of protecting non-smokers," Health Minister Sabine Oberhauser said.

An American clinician has been cured of Ebola and was discharged from a hospital near the US capital, officials said Thursday.

The man, whose identity has not been revealed, was sickened with the often deadly virus while working in Sierra Leone, and was flown to the United States for treatment last month.

An extremely premature Polish infant weighing just 820 grams (1.8 pounds) has become the world's smallest and youngest patient to escape death thanks to an artificial kidney, according to the doctor who oversaw the treatment.

Born 15 weeks early, Kamil nearly died from organ failure a few days later and conventional methods used to keep preterm babies alive proved ineffective.

People who are obese in middle age run a lower risk of developing dementia later, said a large and long-term study Friday whose findings challenge the prevailing wisdom.

On the other end of the scale, however, being underweight in the 40-55 age bracket was associated with a higher risk, the researchers found.

Drug-resistant tuberculosis is a major health challenge across much of Africa, but a new medicine being pioneered in South Africa could be a breakthrough after decades of frustration.

Bedaquiline is being made available to 3,000 people suffering side effects of the usual drug-resistant tuberculosis treatment, or who have developed complete drug resistance.

Short people face a greater lifetime risk of clogged arteries, according to a study out Wednesday that confirmed the long-known link between height and heart disease by examining genetics.

The study is the first to show that the higher risk is primarily due to a variety of genes that influence whether a person is tall or short, and not potentially confounding factors like poverty or poor nutrition.

Canadian health officials broadened a quarantine around two turkey farms to nine Wednesday, after H5 bird flu was detected in one of them.

The virus was detected on a farm near Woodstock, Ontario, about 100 kilometers southwest of Toronto, after the sudden deaths of birds over several days.