There are three ways of diagnosing swine flu which include observation of symptoms, PCR diagnostic test and the rapid diagnostic test. In mild cases of infection which does not need hospitalization, swine flu may be diagnosed by observing the symptoms like fever, cough, runny nose, sore throat, fatigue, headache, body aches and chills. In many cases people suffering from swine flu may also suffer from diarrhea and vomiting. Though these symptoms of flu are not an exact indication of the infection as they may be caused due to various other factors as well, so only a doctor can help you to confirm the infection after diagnosis. PCR diagnostic test is another way of diagnosing swine flu. In this test a nasal swab removes the cells of the inside sinus passage which is send to the laboratory for the testing. Rapid diagnostic test is another way which helps in detecting the influenza A H1N1 virus. This test is generally within 5 days of having symptoms when the person is highly contagious. The definite diagnosis of H1N1 swine flu virus is identified with the help of some particular antigens which are associated with this virus type. The tests for swine flu is not done by all doctors and their laboratories but are only performed at specialized laboratories meant for the same.