The World Health Organization chief warned Monday that swine flu could return with a vengeance despite Mexico's President Felipe Calderon insisting his country has contained the epidemic. WHO chief Margaret Chan said in a newspaper interview that a second wave of the virus “would be the biggest of all outbreaks the world has faced in the 21st century”, puncturing optimism emanating from the outbreak's epicenter. Diplomatic damage from the epidemic also reverberated with China denying it had discriminated against Mexican nationals after dozens were placed under quarantine over the weekend despite showing no signs of the flu. A Mexican embassy official in Beijing said nearly 70 Mexicans had been quarantined across China including in Beijing, Shanghai and the southern city of Guangzhou even though they had no flu symptoms. China's foreign ministry said in a statement: “The relevant measures are not directed at Mexican citizens and are not discriminatory.” Twenty-five people have died from swine flu, according to the WHO which estimates there are nearly 900 cases in 20 countries. All but one of the deaths has been in Mexico. Calderon said Mexico had managed “to contain the epidemic” and was now “in a position to overcome” the A(H1N1) virus. Mexico's Health Minister Jose Angel Cordova said the epidemic peaked between April 23 and 28 and was “in its phase of decline.” But Chan said the end of the flu season in the northern hemisphere meant that while any initial outbreak could be milder, a second wave could be more lethal, reflecting a pattern seen with the 1918 Spanish flu pandemic that killed up to 50 million people. “We hope the virus fizzles out, because if it doesn't we are heading for a big outbreak,” Chan told the Financial Times, adding it could re-emerge in the months ahead “with a vengeance”. “I'm not predicting the pandemic will blow up, but if I miss it and we don't prepare, I fail. I'd rather over-prepare than not prepare.” The UN agency last week raised its alert level to five, one a scale of one to six, indicating a global pandemic is imminent. In an interview with Spain's El Pais newspaper, Chan said it was important to avoid a “wave of panic” if the alert level was raised to the maximum six, adding that such a move would not mean “the end of the world.”More countries are confirming cases every day with Italy and Colombia the latest to join the list, while France announced two new confirmed cases. Japan tripled the number of quarantine officers at Tokyo's Narita airport to try to detect cases at the start of a holiday week.
