Britain's GlaxoSmithKline has already benefited from fears that there could be a flu pandemic. In the first three months of this year governments around the world ordered about £220 million worth of Glaxo's flu drug Relenza, outstripping for the first time orders placed for Swiss rival Roche's Tamiflu, according to data supplied by both companies.
About £182 million of Tamiflu was ordered and the switch in demand came after experts warned that the flu strain H1N1, which includes swine flu, was becoming resistant to Tamiflu. James Knight, analyst at Colins Stewart, said Relenza still has "upside", predicting peak sales of £250 million a year.