Hygienic Laboratory Influenza Surveillance Testing

2019-2020 Testing Guidance

For the 2019-2020 season, SHL and the Iowa Department of Public Health request the following specimens to be submitted for molecular testing at SHL.

I. Influenza Specimen Collection, Submission and Results

Please submit the patient’s specimen to SHL for testing by real-time PCR (RT-PCR) if it meets the criteria as described in the algorithm. RT-PCR is a molecular method of virus detection that is more sensitive and specific than point of care rapid tests.

Specimen Collection

Patients with influenza-like illness (optimally within three days of symptom onset):

Patients hospitalized with pneumonia or other secondary infections when more than seven days have elapsed from the onset of influenza-like illness:

The following specimens should be considered for patients who are intubated or undergoing bronchoscopy:

If a patient with pneumonia or other secondary infection is not intubated or undergoing bronchoscopy, then a combined nasal swab plus throat swab (two swabs in one tube transport medium) or nasopharyngeal swab should be obtained.

Test Request Form

II. Transportation of specimens to SHL

III. Accessing Your Results

IV. Result Interpretation

All testing is performed using the CDC Human Influenza Virus Real–Time RT–PCR Diagnostic Panel and the results are reported as follows:

If a specimen is positive for Influenza A but negative for all subtypes, it is considered inconclusive. This is most likely due to a weakly positive sample that does not contain sufficient amounts of virus for subtyping, but could also reflect an infection with a novel strain of influenza virus. Any of these unusual results are investigated by SHL.

Influenza surveillance serves the following purposes:

Contact Us:

  • Jeff Benfer, Virology and Molecular Biology Supervisor, 319/335-4276
  • Molecular Section, 319/335-4376
  • Last updated Sept. 19, 2019.