British officials are proposing to increase the UK’s stockpile of antiviral drugs by up to six times as they reinforce preparations against a future flu pandemic.

Based on computer simulations of the likely spread of the virus, experts believe it might be worth increasing stocks of the drug Tamiflu, made by Roche, the Swiss-based pharmaceutical group, to between 60m and 90m courses, or up to 1.5 packets for every UK resident.