Visit the CDC or MDH website for more information as it becomes available.
Contact MDH at (651) 201-5414 or (877) 676-5414 for consultation and questions.
Detection of SARS-CoV-2 to assist in the diagnosis of COVID-2019 infections
For medical purposes only; not for travel screening
Please have patient blow their nose prior to NP and nasal collections. Excessive mucus is known inhibitor/interfering substance for molecular testing.
There are no food or drink restrictions prior to collection of nasopharyngeal or oropharyngeal samples for COVID-19 testing
COVID-19/Coronavirus sample collection kit containing viral transport media (VTM), universal transport media (UTM), or phosphate buffered saline (PBS).
Kits have been assembled by the Central Lab to include an NP or OP swab and transport media. Note that the contents of the kits may vary as supply inventory is fluctuating.
Effective 11/2022 - For Allina Health Clinic Ambulatory patients only:
Hologic Direct Load Tube
Use the mini-tip NP swab included in the COVID-19 test kit.
New England Journal of Medicine video on NP swab collection: Nasopharyngeal Swab Collection Video
For Allina Health Clinic Ambulatory patients:
The Hologic Direct Load Tube allows for Nasal/OP collection using the pink proprietary swab.
Nasal collection
OP Collection
COVID-19 sample collection kit
Hologic Direct Load Tube - Allina Health Clinic Ambulatory Patients only
Oropharyngeal swab
Swab placed in phosphate buffered saline (PBS)
Bronchial specimens/sputum
Screw cap plastic container (sterile); do not add viral transport media
Oropharyngeal (OP) swab:
Sputum:
Collect only if the patient has a productive cough, or it is being collected for other clinical reasons
Swab placed in phosphate buffered saline (PBS)
Screw cap plastic container (sterile)
Allina Health Laboratory:
Covid -19 Sample kit
Hologic Direct Load Tube - (Allina Health Clinic Ambulatory)
LabCorp:
Frozen (preferred) - specimens must be frozen if they will not reach the testing laboratory within 72 hours of collection
Refrigerated - 72 hours
Ambient - 24 hours
Varies/multiple
Not detected
Nasopharyngeal (NP) vs oropharyngeal (OP) collections
There is a severe swab shortage. When an NP swab isn’t available, an OP or anterior nares swab is acceptable. The OP swabs can also be used for anterior nares but not for NP (there is no support for using an OP swab as an NP swab).There are some short swabs that can also be used for nares but are too short for OP.
For consistency’s sake and per Mayo’s recommendation for OP as the next step, Allina Health is using OP when NP isn’t available.
Sensitivity
We don’t have a clear answer on sensitivity as there are too many confounding factors. Swabs aren’t the only factor – the viral load is highest for the first few days after symptom onset – swabs collected too early or later in the disease course will have lower sensitivity. This is a confounding factor for published studies that don’t take into account the point in the disease course when the swab was taken.
The most important factor in sampling is to get adequate upper respiratory epithelial cells (where the virus proliferates), and not just secretions.
COVID PCR Lab Testing List for Inpatients and Outpatients
Result reporting
Results are reported to the appropriate state health department based upon the patient's address.
Excessive mucus is a known inhibitor/interfering substance for molecular tests. Review specimen tab for patient preparation.