In this video, Dr. Joe Bresee, with CDC's Influenza Division, describes the
symptoms of swine flu and warning signs to look for that indicate the need
for urgent medical attention.
Swine Flu Outbreak
The 2009 swine flu outbreak or H1N1 outbreak is the spread of a new strain of H1N1 influenza virus that was first detected by public health agencies in March 2009. Local outbreaks of an influenza-like illness were first detected in three areas of Mexico, but the new strain was not clinically identified as such until a month later in Texas and California, whereupon its presence was swiftly confirmed in various Mexican states and Mexico City; within days isolated cases elsewhere in Mexico, the U.S., and several other Northern Hemisphere countries were also identified. By April 28, the new strain was confirmed in Canada, Spain, the United Kingdom, New Zealand and Israel and suspected in many other nations, including South Korea and Austria, with over 2,500 candidate cases, prompting the World Health Organization (WHO) to raise their pandemic alert level to 4. A level 4 warning officially means that the WHO considers that there is "sustained human to human transmission"; whereas levels 5 and 6 represent "widespread human infection".