Pandemic (2009) H1N1 (also known as Novel or Swine-Origin) Influenza A Virus

Mayo Medical Laboratories is committed to offering timely updates and information regarding laboratory testing options for influenza A. After an initial resurgence in 2009, the Pandemic (2009) H1N1 Influenza A is now circulating only at low levels throughout the United States and much of the world. It remains the predominant influenza A strain, but a small number of seasonal influenza A viruses are also being detected.

For detection of both Pandemic (2009) H1N1 and Seasonal influenza A viruses, clients may order the Mayo Medical Laboratories #88544 Influenza Virus Type A and Type B RNA by Rapid PCR.  This is the test of choice for detecting acute illness with any of the influenza viruses. If the result is positive, it indicates that influenza A is present in the sample, but it does not differentiate Pandemic (2009) H1N1 influenza from other seasonal influenza A subtypes.

Alternative Influenza Tests

Although alternative influenza A tests such as culture and serology are available, they are not recommended for primary detection of the Pandemic (2009) H1N1 strain. Rapid antigen detection tests may be available to some clients in their own health care settings, but the sensitivity and specificity of these tests are highly variable, and confirmation of negative results using culture or PCR may be recommended.

To learn more about influenza A and the pandemic (2009) H1N1 strain, utilize the following link:

• CDC H1N1 Web Site