According to the World Health Organization (WHO), 5% to 20% of the world's population is infected each year with an influenza virus. In March 2009, a new strain of flu – H1N1 – appeared in Mexico, and then quickly spread around the world through human-to-human transmission. The sudden appearance of the virus, its capacity for human-to-human transmission, and its rapid worldwide expansion led the World Health Organization to declare a state of pandemic.
In spite of widespread concern about the impact of H1N1, it is important not to panic! This module will tell you about simple steps you can take to stay healthy and prevent the spread of the virus.