Indeed, apart from an 18-year-old and his 10-year-old sister, the four other cases were isolated infections and the victims lived far apart from one another.

For an 18-year-old man from Surabaya in east Java, his work -- sorting feathers in a factory churning out shuttlecocks -- brought him close to possible sources of infection.

And in the case of a 39-year-old man from Jakarta in west Java, he had cleared pigeon feces blocking the roof gutters on his house before falling sick. Pigeons are among the dozens of bird species known to have been infected with H5N1.

Nevertheless, the cases have drawn concern in the scientific community because Indonesia is one of the few places in the world where there has been a steady rise in the number of H5N1 human infections, which is still essentially a disease among birds.

"Of course I am worried, the problem has not improved at all in Indonesia, it's not a good situation. The government and the WHO has to monitor it very closely," said Leo Poon, a microbiologist and H5N1 expert with the University of Hong Kong.

"Surveillance is obviously no good and for such a big country, maybe there should be more education to teach people how to prevent it," he said.

VACCINATIONS MASK VIRUS

Experts say the more entrenched the virus is in people, the greater the chance that it will mutate and learn how to spread efficiently among humans: a necessary precursor to any pandemic.

Soon after the first H5N1 outbreak in chickens in Indonesia in late 2003, the government launched a program to vaccinate chickens with the aim of getting rid of the virus in poultry.

This should logically remove the single biggest, potential source of H5N1 infection for its citizens as many Indonesians live very close to chickens. But that has not happened.

Although the number of chicken deaths from H5N1 has fallen sharply since vaccination began, experts say the virus is now endemic in nearly all of the country's 33 provinces.

Forty-nine people have been infected with the disease and 36 of them have died. Thirty-three of the infections were in 2006.

Bayu Krisnamurthi of the National Committee on Avian Influenza Control and Pandemic Influenza Preparedness said vaccination has helped protect chickens from dying, but not from infection -- and possibly spreading the virus -- a development that is more commonly known as "masking".

"If you vaccinate the chicken, it will survive but the virus is still in the chicken," he said. "Even if you see a healthy chicken, the virus is there."

Such a problem has also been observed in small numbers of chickens in southern China. It is a serious problem because, in the absence of any signs of disease, people are unlikely to take precautions and could therefore be susceptible to infection.

Indonesia's battle with the H5N1 is also made harder because of its massive 1.2 billion to 1.3 billion chicken population.

Chickens roam freely, from the countryside to the heart of its capital, Jakarta, and "backyard chickens" are commonly reared by locals for food and for their livelihood.

The scientists, at the Hebrew University of Jerusalem, examined the DNA of 148 healthy male and female university students and compared the results with questionnaires asking for the students' self-descriptions of their sexual desire, arousal and sexual function. They found a correlation between variants in a gene called the D4 receptor and the students' self-reports on sexuality.

The results suggest that low sexual desire might be a normal biological condition rather than a psychological problem, the researchers say. Further, it might be possible to develop drugs to alter sexual desire based on the new findings.

The research was led by Richard Ebstein and was published in the online version of the journal Molecular Psychiatry.

UNAIDS on Tuesday was scheduled to launch a 630-page report that takes stock of where the world currently stands with nearly 40 million people living with HIV/AIDS. It documents countries' progress and failures, and projects what must happen to keep some regions from experiencing disaster. The report was set to be released a day ahead of a High Level Meeting on AIDS in New York, a week prior to the 25th anniversary of the first documented AIDS cases on June 5, 1981.

"It won't go away one fine day, and then we wake up and say, 'Oh, AIDS is gone,'" Piot said. "I think we have to start thinking about looking at the next generations. There's an increasing diversity in how the epidemic looks."

Piot said that there is still time to stop it from worsening, but action is needed now on a number of fronts.

"Ultimately, it depends on how the leadership reacts, how the international community will continue to respond and how ready communities are to face the problem," Piot said. "Intervention is very low ... for many critical populations in many countries. We need to really intensify the response to AIDS."

Piot said the picture is not hopeless, with examples of progress in nearly every part of the world. He said Thailand and Uganda were two of the only previous examples where exploding epidemics were curbed, but a handful of other countries, including Kenya and Zimbabwe, are also starting to show promise.

Epidemics are diversifying, Piot said, with some driven by unprotected sex, others by dirty needles and some a combination of the two overlapping each other. Those trends must be identified and targeted.

Currently, about 1.3 million people in poor countries have access to antiretroviral treatment, but about 80 percent still are not receiving drugs.

Sub-Saharan Africa continues to be the epicenter of the virus, Piot said. The overall percentage of adults infected in some of the hardest-hit countries continues to climb, with several rates reaching double digits.

"In think in Africa, it is only comparable in demographic terms to the slave trade regarding the impact it has had on the population," Piot said. "In southern Africa, HIV prevalence continues to go up, and they're already the world record."

Piot said that the sheer population of Asia, home to most of the world's population, makes it a potential problem because even small gains in overall per capita infections equal huge numbers - especially in countries like China and India, with over 1 billion people each. More than 5 million people are infected in India alone.

The Asia-Pacific region has 8.3 million people living with the virus, the second-highest after sub-Saharan Africa.

Papua New Guinea, which shares an island north of Australia with Indonesia's easternmost Papua province, has one of the region's worst epidemics in a country plagued by political instability, poverty and rampant sexual violence against women. Piot said it's the only place in the region that resembles an Africa-style epidemic.

Piot said Eastern Europe and Central Asia have become a new front where infections have expanded as people have access to more money and started buying injecting drugs - instead of just shipping them through - from countries like
Afghanistan.

"Absolute numbers are still low, but when you look at the spread of the disease, we know from experience where that leads," Piot said. "The Middle East is the last part of the world where HIV is not spreading rapidly."