Further information:
2009 flu pandemic in Mexico
The virus was first reported in two U.S. children in March 2009, but health officials have said that it apparently infected people as early as January 2008 in
Mexico.
[28] The outbreak was first detected in
Mexico City on March 18, 2009,
[29] immediately after the outbreak was officially announced, Mexico requested material support from the U.S., and within days of the outbreak
Mexico City was "effectively shut down."[
citation needed] Some countries canceled flights to Mexico while others halted trade.[
citation needed] Calls to close the border to contain the spread were rejected.[
citation needed]
Mexico already had hundreds of cases before the outbreak was officially recognized, and was therefore in the midst of a "silent epidemic".
[30] As a result, Mexico was reporting only the most serious cases, possibly leading to a skewed initial estimate of the case fatality rate."
[29]