COVID-19 virus (SARS-CoV-2) – detection

Molecular detection of SARS-CoV-2 virus
Microbiology
Virology
Respiratory: ○ BAL ○ Nasopharyngeal (NP) swab ○ Saliva ○ Sputum ○ Throat swab ○ Tracheal aspirate Other: ○ Products of conception (placenta/conception swab) ○ Breast milk ○ Plasma/serum ○ Stool

○ NP/throat swab: single swab in universal transport medium
○ BAL/ saliva/ sputum/tracheal aspirate : sterile container
○ Plasma: EDTA-blood tube (lavender top) (min volume 5 mL)
○ Serum: serum separator tube/red top tube (min volume 5 mL)
○ Products of conception swab: sterile swab in universal transport medium
○ Stool: sterile container


Respiratory:
BAL:
○ Pass bronchoscope transnasally or transorally (if patient is not intubated) or via endotracheal tube (if patient is intubated). Instill a large volume of 0.85% sterile saline (nonbacteriostatic) into the airway lumen. Discard the initial fluid recovered (likely contaminated). Collect remaining fluid in a clean, sterile container via suction.

Nasopharyngeal swab
○ Insert tip of swab into nostril aiming along the floor of nasal cavity until posterior wall of nasopharynx is reached. Resistance will be felt when reached. Rotate swab for 10-30s. Place swab into transport medium and close tube. Repeat collection with second nostril.

Saliva:
○ Stop patient from swallowing, let saliva pool in mouth. Release and collect saliva in sterile container. Ensure no eating, drinking, smoking, vaping or chewing gum has occurred within 30 min prior to sample collection.
Throat swab:
○ Collect the specimen using a clean, sterile swab by swabbing the posterior oropharynx vigorously and placing it in universal transport medium.

Sputum/tracheal aspirate
○ Collect sputum by expectoration or by tracheal aspiration in sterile container.
○ For endotracheal aspirates, collect aspirated material using a NEW sterile catheter or in-line catheter and aspirate material from the trachea using a syringe or suction device

Products of conception swab
○ Rotate sterile swab over surface between amnion and chorion membranes. Place in transport medium

Plasma/Serum
○ Decontaminate skin with 70% alcohol followed by iodine or chlorhexidine, collect at least 5 mL of blood

Stool
○ Collect stool in a sterile container


Refer to section Sample Processing / Delivery

In-house

○ Up to 48h depending of the priority

416-586-4800 extension 4474

NO

○ Label specimen container. Place specimens in biohazard bag and seal.

○ Specimens should be transported to the UHN/SH Microbiology Laboratory at room temperature (20-25˚C) up to 72h after collection.