Viral Swab Collection Procedure for Infants
For infants requiring viral testing, a nasopharyngeal (NP) swab collected by a healthcare professional using a flocked, synthetic fiber mini-tip swab with plastic or wire shaft is the recommended procedure, as it provides the most reliable specimen for diagnosis. 1
Proper Collection Technique
Nasopharyngeal (NP) Swab - Primary Recommendation
- Tilt the infant's head back gently (approximately 70°) 2
- Insert a flexible shaft mini-tip swab through the nares parallel to the palate (not upwards) until:
- Resistance is met, OR
- Distance is equivalent to that from the infant's ear to nostril 2
- Gently rub and roll the swab to absorb secretions 2
- Leave the swab in place for several seconds 2
- Slowly remove while rotating the swab 2
- Immediately place in sterile tube containing viral transport medium 1
Alternative: Nasal/Anterior Nares Swab
- Insert swab about 1 cm (0.5 inch) inside nares (less depth for infants) 2
- Rotate swab and leave in place for 10-15 seconds 2
- Using same swab, repeat for other nares 2
- Immediately place in sterile tube containing transport medium 1
Equipment Requirements
- Use only: Flocked, synthetic fiber mini-tip swabs with plastic or wire shafts 2, 1
- Never use: Calcium alginate swabs or swabs with wooden shafts, as they may interfere with nucleic acid amplification 2, 1
- Transport medium: Use appropriate viral transport medium as specified by the testing laboratory 1
Additional Specimen Collection Based on Clinical Presentation
For comprehensive viral diagnosis in infants, multiple specimen types may be required:
- For respiratory symptoms: NP swab (primary) or nasal swab 2, 1
- For suspected enterovirus: Consider throat and rectal swabs in addition to respiratory specimens 2
- For vesicular lesions: Collect vesicle fluid using appropriate swabs 2
- For systemic illness: Consider blood samples in addition to respiratory specimens 2
Specimen Handling
- Transport specimens on ice within 1-2 hours after collection 1
- If immediate processing isn't possible, refrigerate specimens 1
- Follow laboratory-specific requirements for transport medium 1
Treatment Considerations
Treatment depends on the identified virus and clinical presentation:
- For respiratory viruses: Most viral respiratory infections require supportive care only 3
- For influenza: Early antiviral therapy may be indicated if testing positive 3
- For suspected HSV or severe viral infections: Empiric antiviral therapy may be initiated while awaiting test results 2
Common Pitfalls to Avoid
- Improper swab type: Using incompatible swabs can interfere with viral detection 1
- Inadequate depth: Insufficient insertion depth may result in false negatives 1, 4
- Delayed processing: Prolonged time to laboratory processing can degrade viral material 1
- Improper technique: Poor collection technique can lead to insufficient sample material 1, 5
- Swab breakage: Excessive force during collection can lead to swab breakage and nasal foreign body complications 4