Swine flu is a communicable disease, and public health authorities worldwide believe in much the same way as seasonal flu. People with the swine flu infection spread it when they cough or sneeze. They can also infect a surface after they wipe their nose with their hand and then touch anything such as a doorknob or sink. The tiny particles that get released into the environment also contain the swine flu virus. Anyone coming in contact with these particles, through air or by touching an infected surface can contract H1N1 swine flu disease. Swine flu causes are basically any of those acts or incidents which lead to the spread of the H1N1 virus.
A person with swine flu can be infectious without even showing symptoms and till 7 days after the symptoms. Children can be contagious for a longer duration, up to 10 days. Despite its name, swine flu is not spread by eating pork. This is a misnomer. It came about because the symptoms of this particular disease were found to be similar to those found in pigs. Later studies have shown that this is not entirely correct because genes of avian and seasonal flu are also present in this virus.
With such an incorrect view of swine flu causes leading to a lot of misnomers, authorities decided to start calling it by its bio-chemical nomenclature, i.e. H1N1. The name swine flu seems to have stuck though.
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