Victims in a flu pandemic will be told to ask a friend to collect their antiviral drugs and deliver them through the letterbox.

The move is one of many being considered for the revised version of Britain’s flu plan, due for release soon.

Health services are likely to be overwhelmed if a pandemic flu strikes, Roy Anderson, of Imperial College, London, told a conference at the Royal Society of Medicine yesterday.

If antiviral drugs are to be effective in reducing symptoms and slowing the spread of the disease, they need to be delivered quickly. So the new plan may call for people to agree to act as couriers for one another.

If one were to fall ill, he or she would contact the other to collect Tamiflu from the GP and deliver it — without shaking hands or touching the victim. The plan means that overworked GPs would be spared from visiting flu victims in their homes, and the patients would not have to go out and so risk spreading the disease.

“Having a friend to help you is a very good idea,” Professor Anderson said.

“The logistics of delivering drugs is hugely important — it’s everything. We learnt that in the foot-and-mouth outbreak. If we are going to have any effect on slowing the spread of flu, you have got to have the drug in 24 hours.

Other plans include including closing schools, but that would be a difficult decision, Professor Anderson said. “Schools are the most extreme mixing environment for respiratory tract infections, but we would have to look at the economic implications. If children stay at home, are we going to bring the country to its knees? My view is that we would have to consider it if the virus is very, very pathogenic.”

Travel restrictions or closing borders was pointless, he said.

To have any useful effect, they would have to close immediately and be 99 per cent impenetrable, which was implausible.

“I do not think people have got to grips with the magnitude of this problem,” he said. “We have had two years at it. A lot of problems have been sorted out but there is a lot more to do.”

Sophisticated mathematical models developed by Professor Anderson’s team can help to predict the spread of pandemic flu.

But until a virus capable of causing such a pandemic emerges, scientists lack two vital pieces of data: the reproductive number (how many people each victim passes the disease on to) and the generation time (the time taken for each infected person, on average, to pass it on). For Sars, the reproductive number was 2.7, but the generation time was long — 17 to 20 days. Victims were at their most infectious almost three weeks after catching it, which meant that isolation was an extremely effective control.

The reproductive number for pandemic flu may well be lower, but the generation time will be two to three days. “So quarantine and isolation will have a very limited effect compared to Sars,” Professor Anderson said. “Sars was a doddle by comparison . . . but it did show what could be done by international cooperation.”

David Reddy, of Roche, the company that makes Tamiflu, said trials had shown that the drug was more than 90 per cent effective in reducing symptoms, but became less efficient the longer the virus remained untreated. “You need to act very early with these drugs. The benefits are great if they are administered early,” he said.

Times Recommends

• Savers left in limbo as Icesave freezes deposits
• Kennel Club changes breeding rules
• Passengers triple risk of fatal crashes