Everything You Need to Know About the Swine Flu Pandemic

Introduction

Swine flu is a human respiratory infection caused by an influenza strain that started in pigs.

The World Health Organization uses the term "(H1N1) 2009 pandemic" when referring to the Swine flu event, and officially adopted the name "A(H1N1)pdm09" for the virus in 2010, after the conclusion of the pandemic.

Swine flu was first recognized in the 1919 pandemic and still circulates as a seasonal flu virus. Swine flu is caused by the H1N1 virus strain, which started in pigs. The April 2009 swine flu outbreak (pandemic) was due to infection with the H1N1 virus and was first observed in Mexico. It began increasing during the summer 2009 and rapidly circulated to the U.S. and to Europe and eventually worldwide. The WHO declared it first fit their criteria for an epidemic and then, in June 2009, the WHO declared the first flu pandemic in 41 years. There was a worldwide concern and people began to improve hand washing and other prevention methods while they awaited vaccine development. Scientists found this virus had originated in pigs as a recombinant form of flu strains from birds and humans. On August 10, 2010, WHO declared an end to the global 2009 H1N1 influenza pandemic. However, (H1N1)pdm09 virus continues to circulate as a seasonal flu virus, and causes illness, hospitalization, and deaths worldwide every year.

Influenza viruses that commonly circulate in swine are called “swine influenza viruses” or “swine flu viruses.”

The incubation period for the disease is about one to four days. Swine flu is contagious about one day before symptoms develop to about five to seven days after symptoms develop; some patients may be contagious for a longer time span. The disease lasts about three to seven days with more serious infections lasting about nine to 10 days.

Swine flu, also known as the H1N1 virus, is a relatively new strain of an influenza virus that causes symptoms similar to the regular flu. It originated in pigs but is spread primarily from person to person. Swine flu made headlines in 2009 when it was first discovered in humans and became a pandemic.