If a doctor suspects a person may have H1N1 or another type of influenza, they may recommend a test to confirm the diagnosis. The most commonly used test for influenza diagnosis is a rapid influenza diagnostic test, which involves taking a sample from the nose or throat with a swab and looking for viral antigens in that sample.

These tests can provide results in about 15 minutes. However, the results are not always perfectly accurate. More accurate rapid molecular assays are also available that can provide quick results. Since there are multiple influenza A virus strains, a positive influenza A test does not necessarily mean the person has the H1N1 virus.

Tests used in the diagnosis of swine flu include:

Nucleic acid amplification tests (RT-PCR)
Rapid antigen tests
Culture – virus isolation
Serological diagnosis (antibody tests)
ELISA

While rapid antigen tests can detect the presence of Influenza A and Influenza B, PCR testing allows for subgroup analysis (H1N1-swine flu).