Swine flu is caused by human version of H1N1 sub-type of influenza A virus. This virus spreads in just the same way as the standard cold and flu viruses (by tiny droplets that are released when a person coughs or sneezes). However as resistance to this new strain lacks in most people, the risk of swine flu infection is increased if they are exposed to the virus.
The virus spreads by tiny droplets that are released when a person coughs or sneezes. The droplets reach a distance of about one metre (3ft). These droplets remain suspended in the air for a short duration, and then settle on a surface. The virus suspended in airborne droplets can infect a person, if the person inhales the contaminated droplet.
Common objects such as door handles, remote control, hand rails and computer keyboards can get contaminated with the virus when the droplet settles on these surfaces. If a person touches these surfaces and places the contaminated hands on their mouth or nose he or she can get the infection. They can spread it further by touching other things. If the droplets land on a hard surface the virus can survive for about 24 hours, and on a soft surface it survives for about 20 minutes.
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