Procedure for Collecting Nasopharyngeal Swabs to Test for Influenza:
Use only sterile Dacron or rayon swabs with plastic shafts. Do not use calcium alginate swabs or swabs with wooden sticks, as they may contain substances that inactivate some viruses and inhibit PCR testing.
Insert swab into the nostril parallel to the palate. Leave the swab in place for a few seconds to absorb secretions. Swab both nostrils.
Swab the posterior pharynx and tonsillar areas, avoiding the tongue.
Place the swabs immediately into sterile vials containing 2 ml of viral transport media. Break the applicator sticks off near the tip to permit tightening of the cap. Label each specimen container with the patient’s ID number and the date the sample was collected. If shipping domestically, use cold packs to keep sample at 4 degrees C. If shipping internationally, pack in dry ice.