World's experts to hold emergency summit on fears over man-made lethal mutant bird flu

* H5N1 bird flu virus kills half of humans that contract it
* Experts say to find treatments research must continue

By Damien Gayle

Bird flu experts meet at the World Health Organisation this week to decide how to continue with genetic research that risks creating a catastrophic pandemic.

The urgent summit is an attempt to settle a row over the censoring of two studies which show how make a highly contagious mutant H5N1 bird flu virus.

Far deadlier than normal flu, H5N1 kills roughly half of humans that contract it, but so far the virus has been mainly restricted to poultry

Experts warn that whatever the outcome of the meeting, censorship will not stop scientists getting the tools to create and release a pandemic H5N1 virus if they were intent on doing so.

'It doesn't matter how much you restrict scientists from doing good, bad people can still do bad things,' said Wendy Barclay, an expert in flu virology at Imperial College London.

The WHO called the 'closed door' meeting, set to begin Friday in Geneva, to break a deadlock between scientists and U.S. biosecurity chiefs.

American officials want to censor the work of two research teams, one in the Netherlands and one in the U.S., who have found that just a small number of mutations would allow deadly H5N1 to spread between mammals like ordinary flu.

The United Nations health body has said it is 'deeply concerned about the potential negative consequences' if the findings were to make their way into the public domain.

On January 20, flu scientists from around the world declared a 60-day moratorium on any research involving H5N1 that could produce more contagious forms of the virus.

At this week's meeting, the researchers who made the findings and the editors of Science and Nature, the two journals asked to withhold publication, will meet officials from the U.S. National Science Advisory Board for Biosecurity (NSABB) which asked for the papers to be censored.

Keiji Fukuda, the WHO's Assistant Director-General for Health Security and Environment, who will chair the meeting, says he would like to secure agreement on whether the studies should be published, in full or part, and who should have access to them.

The findings are seen as vital for scientists to be able to develop vaccines, diagnostic tests and anti-viral drugs that could be deployed in the event of an H5N1 pandemic.

'It is important that research on these viruses should continue,' Mr Fukuda told Reuters. 'They do pose a risk. There's a lot of things we don't know about them.

'The question is not really should we continue to do research ... but under what conditions can we do it so we don't unnecessarily create fears and risks.'

First detected in Hong Kong in 1997, the H5N1 virus remains entrenched among poultry in many countries, mainly in Asia, but so far remains hard for humans to catch.

It is known to have infected nearly 700 people worldwide since 2003, killing half of them, making it far more deadly than the H1N1 swine flu which caused a pandemic in 2009/2010.

Ron Fouchier, the scientist leading the Dutch team that gave H5N1 various genetic mutations and made it transmissible in mammals, argues the research must be published.

He says it could help public health officials better prepare for a scenario where the virus mutates and becomes more deadly, spreading from person to person via coughs and sneezes.

He has also said other research teams around the world are close to the same findings, some of them inadvertently, and should be warned in advance how the virus could become airborne.

In the short term, most scientists agree the moratorium is 'a good gesture,' as flu expert and former WHO health security adviser David Heymann describes it, one that offers the research community space to think.

Still, Mr Heymann, Ms Barclay and many other scientists argue that stopping this type of research into flu viruses and other potentially lethal pathogens would set a dangerous precedent.

Although adding and deleting genes can create super-strains that put the entire world at risk, Heymann said, the work is vital to developing effective vaccines and diagnostic tests which will be needed quickly if a pandemic hits.

Stopping the research would prevent researchers from using all possible scientific options to prepare for naturally occurring, or deliberately caused, outbreaks.

John Edmunds, head of infectious disease epidemiology at the London School of Hygiene and Tropical Medicine, says studies on mutations of H5N1 are 'important work' that must go on.

'This flu strain has the potential to cause such enormous damage, and it's important to know how far away we are from a horrible event like that,' he said.