Swine flu refers to influenza caused by any strain of the influenza virus prevalent in pigs (also called swine).Swine flu is common in swine and rare in humans. People who work with swine, especially people with intense exposures, are at risk of catching swine influenza if the swine carry a strain able to infect humans.

How Swine Flu Virus Spread?

1.Spread in coughs or sneezes
2.Virus can linger on tabletops, telephones and other surfaces and be transferred via the fingers to the mouth, nose or eyes.

Symptoms of Swine Flue:

chills, fever, sore throat, muscle pains, severe headache, coughing, weakness and general discomfort.

Prevention of Spread in Human:

Frequent washing of hands with soap and water or with alcohol-based hand sanitizers, especially after being out in public.

Note: No possible vaccine is available as of now and it is said that sine flu vaccine are being developed and could be ready as early as June 2009.

Source: http://en.wikipedia.org/wiki/Swine_influenza