Midnight, 20 October 2008, Geneva: As reports show sharply rising numbers of patients dying from influenza in south-east Asia, the director-general of the World Health Organisation convenes a meeting to raise the pandemic alert to “phase 5”. Governments and companies brace themselves for a heavy economic and human cost as hospitals fill worldwide, travel restrictions are imposed, schools shut and businesses struggle.

The scenario may be alarming but it is all too plausible – and the role the WHO would play in it is key. Driven in part by the awareness the organisation helped create that a pandemic could spread faster and with more severe consequences than ever before, the power of the WHO has grown from that of a technical United Nations agency, little heeded beyond a narrow circle of health experts, to an institution that wields considerable power.