Swine flu / H1N1 flu is a type of Influenza A virus causing upper respiratory tract illness. Symptoms are similar to other flu viruses like fever, chills, cough, sore throat, stuffy nose, body ache etc. Severe cases may have difficulty in breathing & chest pain. This virus spreads through air droplets when an infected person talks, breathes & sneezes. Factors that increase your chances of getting infected with H1N1 virus are: age below 2 & above 65 years, people living in crowded places, weak immunity, pregnant females & chronic illness.