Final answer:
The 2009 Human H1N1 strain's origin is uncertain but is believed to have started in Mexico. It is less deadly than the 1918 H1N1 strain, and effective global health responses helped mitigate its impact.
Step-by-step explanation:
The 2009 Human H1N1 flu strain was identified during an outbreak that generated a global pandemic. While the exact origins are unknown, epidemiologists traced the pandemic's first apparent signs to Veracruz, Mexico, where factory-style hog farming might have created ideal conditions for this new virus to emerge around January 2009.
Historically, the most lethal influenza pandemic was the 1918 flu, also caused by an H1N1 virus, which resulted from an antigenic shift involving the recombination of avian and human viruses. The 2009 H1N1 strain, although genetically related to its 1918 predecessor, was less deadly, thanks in part to the worldwide response from health organizations.
The Centers for Disease Control and Prevention (CDC) and other public health agencies played a crucial role in monitoring the spread of the 2009 H1N1 pandemic. Using computer models, GIS technologies, and data from previous outbreaks, health officials were able to predict the spread of the virus and effectively allocate resources and vaccines to areas with the highest risk.