As football fans from around the world arrive in South Africa to cheer on their favourite team in the 2010 FIFA World Cup, we must not lose sight of one unwelcome guest'€”HIV. By Michel Sidibé, UNAIDS Executive Director

OPINION: "I've written this article to argue that FIFA, as the world's football authority, has an ethical responsibility for social action, in fact, it owes the soccer-playing world - effectively all of humanity - a massive sustainable and measurably successful longitudinal social project starting from THIS World Cup, a moral imperative on which millions of lives will hang in the balance. By Richard Witzig