British scientists are to travel to south east Asia to investigate how an outbreak of deadly bird flu could be tackled in the future.
A contingency plan for bird flu is to be announced
Experts from the Medical Research Council (MRC) will visit the region where the virus has claimed 60 lives.
The Chief Medical Officer, Sir Liam Donaldson, warned a bird flu pandemic could kill 50,000 people in the UK.
He said a deadly outbreak would come when bird flu mutated with human flu but was unlikely to happen this winter.
Meanwhile, a laboratory at Weybridge is expected to announce on Monday whether Romania has another cluster of bird flu.
It will confirm whether the virus is to blame for the deaths of swans in fish ponds near the village of Maliuc, in the Danube Delta.
Scientists from the MRC, in a team led by Professor Colin Blakemore, are expected to visit China, Vietnam and Hong Kong.
Their findings on how to tackle an outbreak of the virus will be presented to an international conference in London in December.
The organisation, which discovered the flu virus in 1933, is considered a world leader in the field.
Sir Liam told the BBC that bird flu would probably kill about 50,000 people in the UK and a death toll of 750,000 was "not impossible".
"In a normal winter flu year... flu actually kills in excess of 12,000 people," he said.
But the epicentre of any new strain was likely to be in East Asia, Sir Liam added.
The UK has so far stockpiled 2.5m doses of anti-viral drugs - and may restrict travel if there is an outbreak.
On Saturday, UK tests confirmed a case in Romania of a strain of bird flu which is potentially deadly to humans, sparking fears avian flu could spread to the UK through migrating birds.
Sir Liam said it was "less likely" that any new flu strain would come this year.
However he said that if the flu first emerged in another part of the world it would give UK scientists time to try to create an effective vaccine against the virus before it arrived in the UK.
He said a contingency plan was being released on Thursday, outlining the steps the government would take in the event of an outbreak.
Dr Martin Wiselka, consultant in infectious diseases at Leicester Royal Infirmary, said a death toll of 50,000 was a "complete guess".
"It could be worse, it could be better. I think initially it could be worse than that," he said.
"When a new strain arrives it tends to be more virulent but then it slows down. But the honest answer is we don't know."