The present H1N1 strain discovered in the spring of 2009, almost 90 years from the onset of the 1918 pandemic, is resurrecting this specter from the past. This novel H1N1 infl uenza strain emerged from a quiet village in Mexico. The Mexican government responded on 24 April 2009, closing schools, canceling public gatherings in Mexico City and surrounding states until 6 May 2009 [4] . This drastic step may have slowed down the regional spread of H1N1 in Mexico, but it had already left the country through international trade and travel. As in past quarantines, this quarantine would fail as well [5] .