A new and potentially deadly infectious disease emerges somewhere in the world every year, threatening "devastating consequences" across the globe, warns the Lords intergovernmental organisations committee. Its report, published today, criticises Britain's "poorly coordinated" disease control systems.

Reform of the World Health Organisation (WHO) is "essential", as the global health agency is "dysfunctional" and lacking the organisation and resources to curb a major outbreak, it says.

The committee calls for new international disease surveillance systems in developing countries. The report says peers were given the following "sobering" advice by government ministers: "While there has not been a pandemic since 1968, another one is inevitable … Estimates are that the next pandemic will kill between 2 million and 50 million people worldwide and between 50,000 and 75,000 in the UK. Socio-economic disruption will be massive."

Three-quarters of new human diseases originate from animals, but experts have warned they are currently identified only after people are infected. The committee chairman, Lord Soley, said: "The last 100 years have seen great advances in public health and disease control through the world, but globalisation and changes in lifestyles are giving rise to new infections and providing opportunities for them to spread rapidly.

"We are particularly concerned about the link with animal health."

More than 30 countries have reported outbreaks in the past year, in most cases involving wild birds such as swans.

The virus has killed at least 201 people since 2003, according to the WHO. Countries with confirmed human deaths are: Azerbaijan, Cambodia, China, Egypt, Indonesia, Iraq, Laos, Nigeria, Thailand, Turkey and Vietnam.

In total, the virus is known to have infected 329 people since 2003, according to the WHO. Many of the dead are children and young adults.

The WHO says that Vietnam and Indonesia have the highest number of cases, accounting for 132 of the total deaths.

The H5N1 virus is not new to science and was responsible for an outbreak of highly pathogenic avian influenza in Scotland in 1959. Britain confirmed new cases in birds in Scotland in April 2006 and in eastern England in February 2007.

H5N1 is not the only bird flu virus. There are numerous strains. For example, an outbreak in 2003 of the H7N7 bird flu virus in the Netherlands led to the destruction of more than 30 million birds, around a third of the country's poultry stock. About 2.7 million were destroyed in Belgium and around 400,000 in Germany. In the Netherlands, 89 people were infected with the H7N7 virus, of whom one (a veterinarian) died.

The H5N1 virus made the first known jump into humans in Hong Kong in 1997, infecting 18 people and killing six of them. The government ordered the immediate culling of the territory's entire poultry flock, ending the outbreak.

Symptoms of bird flu in humans have ranged from typical influenza-like symptoms, such as fever, cough, sore throat and muscle aches, to eye inflammations (conjunctivitis), pneumonia, acute respiratory distress, viral pneumonia, and other severe and life-threatening complications.

A mathematical analysis has confirmed that H5N1 avian influenza spread from person to person in Indonesia in April, U.S. researchers reported on Tuesday.

They said they had developed a tool to run quick tests on disease outbreaks to see if dangerous epidemics or pandemics may be developing.

Health officials around the world agree that a pandemic of influenza is overdue, and they are most worried by the H5N1 strain of avian influenza that has been spreading through flocks from Asia to Africa. Photo

It rarely passes to humans, but since 2003 it has infected 322 people and killed 195 of them.

Most have been infected directly by birds. But a few clusters of cases have been seen and officials worry most about the possibility that the virus has acquired the ability to pass easily and directly from one person to another. That would spark a pandemic.

The cluster contained a chain of infection that involved a 10-year-old boy who probably caught the virus from his 37-year-old aunt, who had been exposed to dead poultry and chicken feces, the presumed source of infection. The boy then probably passed the virus to his father. The possibility that the boy infected his father was supported by genetic sequencing data. Other person-to-person transmissions in the cluster are backed up with statistical data. All but one of the flu victims died, and all had had sustained close contact with other ill family members prior to getting sick -- a factor considered crucial for transmission of this particular flu strain.

In an attempt to contain the spread of the virus, the local health authorities eventually placed more than 50 surviving relatives and close contacts under voluntary quarantine and all, except for pregnant women and infants, received antiviral medication as a precaution.

"The containment strategy was implemented late in the game, so it could have been just luck that the virus burned out," Longini said. "It went two generations and then just stopped, but it could have gotten out of control. The world really may have dodged a bullet with that one, and the next time we might not be so lucky," he said.

The world is years away from stamping out bird flu in poultry, and the threat of a human pandemic will remain until it does, the head of the World Health Organization (WHO) said on Monday.

Addressing the U.N. agency's 34-state executive board, WHO Director-General Margaret Chan said that in the past three years the H5N1 bird flu virus had proven virulent.

"As long as the virus continues to circulate in birds, the threat of a pandemic will persist. The world is years away from control in the agricultural sector," she said.

"Influenza viruses are notoriously sloppy, unstable and capricious. It is impossible to predict their behavior," she told the board, which meets twice a year.

"The message is straightforward: we must not let down our guard," she said.

Half of the cases occurred in people under the age of 20 years; 90% of cases occurred in people under the age of 40 years.

The overall case-fatality rate was 56%. Case fatality was high in all age groups but was highest in persons aged 10 to 39 years.

The case-fatality profile by age group differs from that seen in seasonal influenza, where mortality is highest in the elderly.

The overall case-fatality rate was highest in 2004 (73%), followed by 63% to date in 2006, and 43% in 2005.

Assessment of mortality rates and the time intervals between symptom onset and hospitalization and between symptom onset and death suggests that the illness pattern has not changed substantially during the three years.

Deaths from the disease surged in the winter for the last three years, the report released Friday said, so a rise in fatal cases can be expected late this year even if the virus does not mutate into a form more easily transmitted.

Moreover, the report warned, the risk of the virus becoming more transmissible remains high "because of the widespread distribution of the H5N1 virus in poultry and the continued exposure of humans."

About 13 000 people were quarantined in the Romanian capital on Monday as troops and police sealed off streets in response to the city's second bird-flu outbreak, said officials.

The mayor of the southern fourth district, Adrian Inimaroiu, said residents would be cut off and all businesses in the area would be closed during the quarantine period of up to three weeks.

The move came after the agriculture ministry earlier on Monday confirmed the presence of the H5 bird-flu virus in dead chickens found in the neighbourhood, the latest of dozens of outbreaks of avian flu in Romania this spring.

Inimaroiu said, urging residents to stay calm, that "about 40 streets have been blocked" in the Luica quarter.

All seven people infected with bird flu in a cluster of Indonesian cases can be linked to other patients, according to disease trackers investigating possible human-to-human transmission of the H5N1 virus.

A team of international experts has been unable to find animals that might have infected the people, the World Health Organization said in a statement today. In one case, a 10-year- old boy who caught the virus from his aunt may have passed it to his father, the first time officials have seen evidence of a three-person chain of infection, an agency spokeswoman said. Six of the seven people have died.

Almost all of the 218 cases of H5N1 infections confirmed by the WHO since late 2003 can be traced to direct contact with sick or dead birds. Strong evidence of human-to-human transmission may prompt the global health agency to convene a panel of experts and consider raising the pandemic alert level, said Maria Cheng, an agency spokeswoman.

"Considering the evidence and the size of the cluster, it's a possibility," Cheng said in a telephone interview. "It depends on what we're dealing with in Indonesia. It's an evolving situation."

"There's no supporting evidence to suggest that this is a continuing environmental source that we've uncovered yet in the investigation," said WHO spokesperson Dick Thompson.

"The investigation is still ongoing. We wouldn't discount the possibility that it is human-to-human transmission."

Limited spread of the virus among people is believed to have happened on several previous occasions. But in each of these suspected cases, transmission of the virus petered out. Sustained human-to-human spread of the virus would be needed to trigger a pandemic.

Meanwhile, an Indonesian official revealed that the man who died Monday refused treatment and fled from authorities after falling ill - behaviour that highlights the difficulties of disease containment in settings where an unfamiliar disease is extracting a high death toll.

In North America we have an expression: "Give it the old college try."

In other words, when the other team is leading and the game is almost lost, don't give up. Make one more attempt to score a goal and win the game.

Since last summer, health authorities have considered the chance of smothering a pandemic outbreak in its cradle: Identify a real human-to-human spread. Send in an army of medical experts. Give Tamiflu or some other antiviral to every human being you meet in the neighbourhood. Kill every duck and chicken. Then hope you stamped it out.

Given the ominous outbreaks in Tanah Karo and Surabaya, I can well imagine that the Americans would ship Tamiflu to Indonesia. It would probably do more good there than in Los Angeles or Miami.

The UK's chief veterinary officer, Debbie Reynolds, said bird flu could stay in Britain for some time.

"We simply don't know, but of course that's why we've got our programme of wild bird surveillance.

"It's been very extensive; over 3,000 wild birds tested already this year, and over 400 swans.

"There are more under way, being tested at the moment, and any wild swan that's reported found dead should be collected and tested," Dr Reynolds said.

"So the arrival of one bird in Scotland does not really add to the risk of this virus emerging as a human strain.

"I will be eating chicken tonight but it will be well-cooked chicken. The evidence from the Food Standards Agency is that in properly cooked meat the virus is killed."

Following the detection of bird flu, the Afghan government has put an immediate ban on poultry imports from neighbouring Pakistan.

Nine hundred chicken farms have been closed in Jalalabad and the government and the UN plan to begin culling birds in the affected areas.

The BBC's Bilal Sarwary in Kabul reports that chicken has started disappearing from markets in Jalalabad and Kunar but are available elsewhere in Mazar-e-Sharif and Herat.

UN and Afghan government officials say a public awareness campaign about the virus is going to be launched.

In testimony to a congressional panel on his agency's budget for combating a possible avian flu outbreak among humans, Leavitt told senators that no one knows when or if the virus will pose a threat to people. But, he said, "it's just a matter of time -- it may be very soon" when wild birds and possibly poultry flocks contract the disease.

Leavitt said that infection of birds alone in the United States with the H5N1 virus would not create a public health emergency. Such an emergency would occur if the disease mutated so that it became easily transferred from human to human.

Nevertheless, Democrats on the Senate Budget Committee criticized the Bush administration's preparedness, saying not enough federal funds were being allocated for vaccine production, stockpiling other medical supplies, disease detection and community readiness.

"It could be the disaster of our time. Two billion dollars is not enough," North Dakota Sen. Kent Conrad (news, bio, voting record), the senior Democrat on the committee, told Leavitt.

Conrad was referring the $2.3 billion in additional emergency funds the Bush administration has requested from Congress. Late last year, Congress approved a first injection of more than $3 billion in emergency money.

The study, prepared for the Sydney, Australia-based Lowy Institute think tank, says there are "enormous uncertainties" about whether a flu pandemic might happen, and where and when it might happen first.

But it says even a mild pandemic could kill 1.4 million people and cost $330 billion.

In its "ultra" or worst-case scenario, Hong Kong's economy is halved, the large-scale collapse of Asian economic activity causes global trade flows to dry up, and money flows out to safe havens in North America and Europe. Deaths could top 28 million in China and 24 million in India.

Dr Nabarro said the WHO was anticipating further outbreaks in other parts of Africa.

"If it's in Nigeria it might also be in other countries that are less well-equipped."

He said governments and ordinary people would have to take "very, very strong precautions" to protect themselves and stop the disease spreading.

"We've got to have all countries, particularly in West Africa, being very vigilant for bird die-offs, which are the indicator of bird flu being in the population."