British scientists travelling to Asia to inspect the spread of bird flu said the number of cases reported in humans could be only "the tip of the iceberg".
Since 2003, around 120 people have been diagnosed with the potentially lethal strain of the virus H5N1, leading to 60 deaths. It is feared the deadly virus could genetically mutate into a form that can be passed easily between people, sparking a global pandemic, and as the avian flu spreads from Asia to Europe, human concerns have grown.
The British delegation from the Medical Research Council (MRC) hope their visit to China, Vietnam and Hong Kong will promote collaboration and co-operation on a global scale.
Sir John Skehel, director of the MRC National Institute for Medical Research, said part of the reason for making the trip was to look at the way the disease was being monitored in other countries.
The MRC scientists said it was impossible to predict the chances of bird flu becoming a significant risk to humans.
The British government is furiously stockpiling the antiviral drug Tamiflu at the rate of 800,000 courses of treatment per month. But although Tamiflu might stem the reproduction of H5N1 in humans, it will not be able to cure it.
PA