Governments have rushed to defend their citizens against possible attacks with weapons such as anthrax, but experts at a two-day forum in Tokyo warned on Wednesday that diseases targeting livestock and crops could expose many countries to potential economic ruin.

Scientists and policy makers from around the world wrapped up the forum on Wednesday, urging nations to create a better international framework, possibly modeled after the World Health Organisation, to contain global outbreaks of diseases that might be triggered by a biological weapons attack.

They said genetic engineering has already advanced to the level of making new viruses, and may soon be harnessed to spawn deadly bacteria as well.

One problem in containing biological weapons is that they are difficult to detect because they piggyback on the same technology used to produce regular medicines, the experts said.

Carolyn Leddy, a senior adviser at the US State Department's Bureau of International Security and Nonproliferation, said: "We need to create a new toolbox to deal with the new threats that we face".

"We need to create a new toolbox to deal with the new threats that we face"

Carolyn Leddy,
Adviser,
US State Department's Bureau of International Security and Nonproliferation

Several countries also lack basic laws against biological weapons.

MR Dando, of the University of Bradford in Britain, warned that terrorists wanting to unleash economic chaos would be well served by targeting livestock and crops, which have traditionally gone unprotected.

The conference was sponsored by the Tokyo-based Centre for the Promotion of Disarmament and Nonproliferation in conjunction with the Japanese Foreign Ministry.