David Nabarro, the senior UN system coordinator for avian and human influenza, painted a graphic picture of the effect of such defensive measures to the House of Lords science and technology committee, which he said would make it harder to check the spread of disease.
What could happen was clear from the preparations being made by big companies, he said. "Large multinational companies have started to do their own risk assessments and risk planning," said Dr Nabarro, giving evidence to the committee's inquiry into pandemic influenza.
"I find them very, very scary. They are about closing down, retrenching, locking the doors, one or two months' survival rations ... their own Tamiflu stocks. That sort of response will make the task (of dealing with the pandemic) very, very difficult."
Dr Nabarro, speaking by videolink from the US where George Bush was launching his pandemic flu strategy, said it would be necessary to move very fast once the virus began to spread easily between humans. "It looks as though we really do only have a window of about three weeks to get moving if we are going to delay the pandemic at source," he said.
Not only the health and agriculture ministries but also the defence ministries in each country would be essential to dealing with the pandemic. The military would have to be called upon for help in getting essential professional staff to disease outbreaks quickly.
"I believe it will be necessary to have dialogue with military capability," Dr Nabarro said. "Given that we are going to have very limited time to move staff and we don't know to where that is going to be and there may be difficulties with civilian transport once the first rumours begin, we are going to have to use military transport."
It was important to think about "what steps we can take to try to prevent there being a general lock-down the moment the thing starts", he said. He believed each country should have its own minister responsible for coordinating the response to a flu pandemic, who would be at a higher level than the individual ministers of health, agriculture and defence.
"All the evidence I have had over the last few months is that it is very hard to get government departments and ministers to work together in a joined-up way on contingencies unless they are encouraged by the highest authority," he said.
Earlier, the government's adviser on immunisation revealed that talks were going on with the pharmaceutical companies over the possibility of protecting them from being sued if a fast-tracked flu vaccine had serious side-effects for some people. David Salisbury had been asked by Lord Winston, a member of the Lords' committee, whether it would be possible to indemnify drug companies against "adverse consequences" in the interests of cutting through the bureaucracy involved in the drug licencing process.
"It is certainly being discussed on both sides of the Atlantic because manufacturers feel very vulnerable on the issue of preparing a vaccine that is not going through all the usual steps," said Dr Salisbury, sitting alongside Rosie Winterton, a health minister.
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