Specimen:

Nasopharyngeal Swab/Aspirate/Wash, Tracheal Aspirate, Bronchoalveolar Lavage, Bronchial Wash

Collection Medium:

Rejection Criteria:

Sputum or dry swab

Testing
Schedule:

0700-1630, 7 days a week, including holidays.

Analytic Time:

Results for respiratory antigen detection by DFA are provided the same 
day if specimen is received in the Microbiology lab by 1430. 
Respiratory virus culture will only be set up if the DFA is negative. 
Culture results are available in 48 h.

Comments:

Screening test for Influenza A (including H1N1) and B, Adenovirus, 
Respiratory Syncytial Virus, Parainfluenza 1, 2, and 3.  Sensitivity of 
the DFA is dependent on adequacy of the specimen. Culture will be 
ordered to confirm negative DFA results.

The influenza A/B antigen detection by DFA and respiratory virus 
culture tests will detect novel influenza A (H1N1) as "influenza A." 
Specimens from hospitalized patients that are positive for influenza A 
will be sent to UHL for subtyping.

Methodology:

Direct Fluorescent Antibody (DFA)

Sample
Processing:

Indicate specimen/fluid type on requisition.
Label transport tube with two patient identifiers, date and time of 
collection.
Maintain sterility and forward promptly to lab.
Specimen should be collected and packaged as close to shipping time as 
possible.
Submit in leakproof container.
Specimen source is required on requisition for processing.

Sample
Storage:

Refrigerate.

Transport
Instructions:

Coolant packs up to 8 hours.
Place coolant packs into styrofoam container.
Place requisition into outside pocket of bag.
Recommend express mail or equivalent if not on courier service.

Instructions:

Collect nasopharyngeal swab in viral transport medium (33595). 
Alternatively, collect tracheal aspirate, bronchoalveolar lavage, 
bronchial wash, or nasopharyngeal wash/aspirate in sterile, leak-proof 
container.

Nasopharyngeal swab: Collect specimen using the flexible minitip 
flocked swab (Hospital Stores #33595).
A. Measure the distance from the patient's nostril to the nasopharynx
   (half the distance from nostril to base of the ear) and hold the
   swab at that location. Do not advance the swab beyond that point.
B. Gently insert the swab along the base of one nostril (straight
   back, not upwards) and continue along the floor of the nasal
   passage until reaching the nasopharynx.
C. Rotate swab 2-3 times and hold in place for 5 seconds. Place swab
   in tube containing viral transport medium. Break off the excess
   length of swab at the score mark to permit capping of the tube.

Nasopharyngeal wash/aspirate:
A. Assemble equipment:
   Sterile specimen trap
   Personal Protective Equipment (gloves, surgical mask, eye
     protection)
   Appropriate size suction catheter (8 fr for infants/children,
     10/12 fr for adults)
   Normal saline vial
   Wall suction
   Bag or cup of ice for specimen transport to laboratory
B. Place patient with the head tilted slightly back.
C. With sterile gloved hand, insert suction catheter into the
   patient's nose to the depth of the nasopharyngeal area (beyond the
   turbinates).  Do not remove catheter until end of procedure.
   (see diagram)
D. With the non-sterile gloved hand, instill approximately 1-2 mL
   normal saline outside the catheter.
E. Apply suction to aspirate nasopharyngeal secretions.
F. Above steps may need to be repeated to obtain 1 mL sample in
   specimen trap.
G. Remove catheter from patient. With specimen trap still in-line,
   rinse catheter with remaining saline to clear secretions.
H. Specimens transported by tube system must be transferred from trap
   to a leak-proof sterile container (be sure the lid is tightly
   secured).

See also:
Viral Culture