Watch the BMJ/The Bureau of Investigative Journalism's video on WHO and disclosure. This video has also appeared on Al Jazeera and guardian.co.uk.

Next week marks the first anniversary of the official declaration of the influenza A/H1N1 pandemic. On 11 June 2009 Dr Margaret Chan, the director general of the World Health Organization, announced to the world’s media: “I have conferred with leading influenza experts, virologists, and public health officials. In line with procedures set out in the International Health Regulations, I have sought guidance and advice from an Emergency Committee established for this purpose. On the basis of available evidence, and these expert assessments of the evidence, the scientific criteria for an influenza pandemic have been met…The world is now at the start of the 2009 influenza pandemic.”

It was the culmination of 10 years of pandemic preparedness planning for WHO—years of committee meetings with experts flown in from around the world and reams of draft documents offering guidance to governments. But one year on, governments that took advice from WHO are unwinding their vaccine contracts, and billions of dollars’ worth of stockpiled oseltamivir (Tamiflu) and zanamivir (Relenza)—bought from health budgets already under tight constraints—lie unused in warehouses around the world.

A joint investigation by the BMJ and the Bureau of Investigative Journalism has uncovered evidence that raises troubling questions about how WHO managed conflicts of interest among the scientists who advised its pandemic planning, and about the …