Many primary care providers have reached out seeking guidance about how to conduct point of care (POC) testing in their offices. Current data indicate that most rapid point of care tests have decreased sensitivity compared to hospital/laboratory-based PCR assays, especially in asymptomatic individuals.
Although POC tests may be useful in some circumstances, a negative POC test in a child with a high pretest probability (such as known exposure or consistent symptoms) should be verified by a more sensitive laboratory-based PCR assay.
Get more information about POC testing from the CDC and CDPHE.
How to collect a nasopharyngeal swab specimen in your office and send it to our lab
For community providers who are interested in collecting patients’ nasopharyngeal (NP) swab samples and couriering them to Children’s Colorado for processing, please refer to the information below.
All testing must be accompanied by a lab order with matching patient details (spelling of names and DOB) between specimen and paperwork or testing will be held or discarded.
NP swab testing instructions
For information on how to collect a nasopharyngeal swab, download the NP Swab Collection (.pdf) document.
Provider office specimen collection details
The table below is in order of preferred specimen type. All specimens are required to have parafilm around the top of the specimen to ensure they do not leak and should be placed in a biohazard bag with the paperwork in the outside pocket.
||Viral, UTM, amies or sterile saline
|Nasal MT swab
||Viral, UTM, amies or sterile saline
|Bronchoalveolar lavage (BAL)
- At-home collections are not permissible for SARS-CoV-2 testing.
- Any specimen types besides NP swab, MT swab, nasal wash, tracheal aspirate or BAL could have decreased sensitivity.
Sending specimens to the Children’s Colorado laboratory
- Please utilize a courier service to have specimens delivered to:
- Children’s Hospital Colorado
Attn: Clinical Lab – Microbiology
13123 E. 16th Ave, RM B0200
Aurora CO 80045
- Couriers will enter our facility through our dock and be screened daily before being allowed to come into the lab.
Ordering information and requirements
- In Epic/PedsConnect/ChildrensConnect:
||Lab order to use/indicate:
|Respiratory Pathogen Panel (RPP)
|SARS-CoV-2/Influenza A/Influenza B/RSV PCR (Flu-VID )
- The RPP automatically includes SARS-CoV-2 testing. There is no longer a need to order both tests.
- RPP can now be ordered with NP swab and MT swab sources. No exceptions.
- If you do not have access to Epic/PedsConnect/ChildrensConnect please reach out to LabClientServices@childrenscolorado.org for a lab requisition.
- We are required to report all patient demographics (including address and phone number); please be sure to include a face or demographic sheet with all specimens. This is a requirement.
- A diagnosis code is a requirement, so please provide the code (not a description) with all submissions.
- Please make sure all patient information is legible. If the spelling of the patient name does not match between the specimen and the paperwork, the specimen could be rejected or results could be delayed.
Children’s Colorado mobile collection details
All patients need an appointment and order placed before arriving at a testing site.
The North Campus, South Campus and Anschutz Medical Campus mobile testing sites are no longer in operation.
For primary care practices: saliva testing drop-off
Practices can drop off samples at the outpatient labs at the following locations. We accept saliva samples from primary care practices only.
South Campus: 7 a.m. – 5:30 p.m., Monday to Friday and 8 a.m. to 12 p.m., Saturday
North Campus: 7 a.m. – 5:30 p.m., Monday to Friday and 8 a.m. to 12 p.m., Saturday
What testing platforms are available at Children’s Colorado for SARS-CoV-2 detection?
- All the testing platforms used at Children’s Colorado are polymerase chain reaction (PCR) based assays that detect viral RNA.
- Since Oct. 6, 2021, we have been running four platforms for respiratory PCR testing. All tests include a SARS-CoV-2 target:
- Abbot m2000 Real-Time will perform SARS-CoV-2-only testing. This platform detects RdRp and N genes of SARS-CoV-2.
- DiaSorin Simplexa will perform Flu-VID testing, which includes SARS-CoV-2, influenza A, influenza B, and RSV targets. This platform detects ORF1ab and S genes of SARS-CoV-2.
- Cepheid Xpert Xpress will perform Flu-VID testing, which includes SARS-CoV-2, influenza A, influenza B, and RSV targets. This platform detects the E and N genes of SARS-CoV-2.
- Biofire RPP 2.1 includes a SARS-CoV-2 target and detects the S and M genes.
- All platforms utilize two different gene targets, which provide optimal sensitivity and minimizes potential for missing detection of virus due to potential new mutations.
Turnaround times (TAT) and resulting process:
|Type of Test
||Turnaround Time from receipt in Microbiology Laboratory
|SARS-CoV-2 / Influenza A / Influenza B / RSV PCR (Flu-VID) PCR
|RPP (Respiratory Pathogen Panel, includes SARS-CoV-2) PCR
- Providers with Epic/PedsConnect/ChildrensConnect should check their inbox or the patient’s chart to see results.
- Providers without Epic/PedsConnect/ChildrensConnect and have submitted a paper requisition for orders will receive results via faxing [make sure fax number is correct on lab order].
- If it has been more than the TAT indicated above for the specific test ordered from sample receipt in the lab and the patient's chart does not have a result or a fax has not been received, please email LabClientServices@childrenscolorado.org.
- If emailing, include patient's first and last name, DOB and the fax number and a result or update will be sent to you within two hours during business hours (Monday through Friday from 8 a.m. to 4 p.m.)
- We highly recommend encouraging patients to sign up for MyChart. Negative results will be uploaded in the system after completion and positive results will be uploaded within the TAT times specified above.
- Our lab is not calling positive results to external providers or their patients. The provider's office will need to notify their patients.
Can I request a specific testing platform when placing an order?
- No. To optimize workflow processes in the laboratory and due to the equivalency between assays, samples will be run when received on the next available platform. Our goal in the Microbiology Laboratory is to provide optimum results in the least amount of time that supports isolation and medical decisions for the patient.
What is the sensitivity and specificity of our SARS-CoV-2 assays?
- All currently available assays for the detection of SARS-CoV-2 RNA have been granted FDA EUA (Emergency Use Authorization) or FDA clearance. For tests that have FDA EUA, no clinical trials have been conducted and there is no available data regarding the overall clinical sensitivity and specificity of these assays. Currently, there is no gold standard diagnostic test of comparison studies to determine the sensitivity and specificity of individual assays. In lieu of definitive clinical sensitivity data, the limit of detection data has been provided as a proxy measure. Similar to other viral detection methods, PCR has become the gold standard for the detection of the virus in respiratory, gastrointestinal and sterile fluids.
- To assess overall performance, the manufacturers of all the assays we are using conducted studies using approximately 100 contrived samples (Abbott – used RNA spiked into samples) or comparator clinical sample (DiaSorin – utilized samples from three different sites in Italy). All assays had 100% negative percent agreement and 100% positive percent agreement, which are terms that describe analytical sensitivity and specificity, respectively, when a new test is evaluated by a comparator assay that is not a diagnostic gold standard.
- The manufacturers of these assays also conducted studies to assess specificity by running samples that were known to be positive for the other six known human coronaviruses and a diverse panel of other common respiratory pathogens, and all assays demonstrated no cross-reactivity, thereby confirming excellent specificity.
- In addition to the manufacturer’s studies, we conducted our own internal verification studies, which demonstrated assay performance that is in accordance with the manufacturer’s claims.
Effectiveness of MT swab testing
Accumulating evidence in the literature indicates that the sensitivity and specificity of a MT swab is relatively similar to an NP swab.
What is the limit of detection for the testing platforms that detect SARS-CoV-2 at Children’s Colorado?
- The limit of detection for our assays is in the range of 100 – 500 viral genomic RNA copies/mL, which is considered extremely low (meaning the assays can detect a very small amount of virus).
What do we know about SARS-CoV-2 viral load in clinical specimens?
- In one study of symptomatic adults with COVID-19, the mean viral load in nasal swabs from positive patients was 1.4 x 106 (1,400,000) copies/mL. Another study in symptomatic adults demonstrated viral loads in nasal swabs ranging from 1.5 x 104 to 1.5 x 107 copies/mL, depending on the day of illness.
- Viral loads are higher earlier in the course of the disease.
- Viral loads are highest in nasopharyngeal (NP) swab specimens.
- Some studies have suggested that adults with more severe disease tend to have higher viral loads.
- Patients with milder disease tend to have earlier viral clearance.
- In pediatric patients, generally, viral loads are known to be higher in symptomatic patients compared to asymptomatic patients.
What is the risk of a “false negative” test result?
- All our assays have excellent performance characteristics. Provided that a sample contains virus in the amount greater than our limit of detection, the risk of a false negative is extremely low.
- Clinical false negatives are usually not a result of test performance. Reasons for clinical false negatives could include:
- Poor sample collection.
- Degradation of viral RNA during shipping or storage of samples (rare).
- Intermittent shedding of virus.
- Stage of infection – very early in the course of an infection (during the incubation period, likely prior to contagiousness), or late in the course of disease viral loads may be undetectable.
- Type of specimen –– some studies have demonstrated that in patients with severe lower respiratory tract disease, upper respiratory tract specimens (NP swabs/nasal washes) may be negative. For these patients, a tracheal aspirate (TA) or bronchoalveolar lavage (BAL) should be considered for testing if the NP swab or nasal wash specimen is negative.
- Although only recommended in certain circumstances, the ability to detect the presence of virus in asymptomatic compared to symptomatic patients should be equivalent.
How will our patients be charged?
- We will bill your patient’s insurance directly, so please provide a diagnosis code along with insurance information (i.e. payor, plan type, subscriber ID, subscriber DOB, etc.) for your patients.
- Please also provide us with a good contact to reach out to if we have questions regarding the information we have been provided or if we have issues getting the insurance approved.
Who can we contact if we have questions?
- For results, please email Lab Client Services and include your patient's first and last name and DOB. Or during normal business hours (Mon. – Fri. 8 a.m. – 4 p.m.) you can call 720-777-6711.
- For details on sending specimens, billing or other inquiries please reach out to the Supervisor of Lab Client Services, Amber Rodriguez, at Amber.Rodriguez@childrenscolorado.org or 720-777-2723.
- Email will provide a quicker response, so please include a good phone number.
- Please remember that our teams are doing the absolute best that we can to manage a significant volume of specimens and maintain a 24-hour TAT. We ask that you be patient with our teams and utilize our Lab Client Services email for inquiries so that our lab techs can focus on testing.
- Casto A, et al. “Comparative Performance of SARS-CoV-2 Detection Assays using Seven Different Primer/Probe Sets and One Assay Kit .” medRxiv, 2020.
- Kam K-Q, et al. “A Well Infant With Coronavirus Disease 2019 With High Viral Load.” CID, 2020.
- Kim J.Y. et al. “ Viral load kinetics of SARS CoV-2 infection in first two patients in Korea. J. Korean Med Sci., 2020.
- Liu Y, et al. “Viral Dynamics in Mild and Severe Cases of COVID-19.” Lancet Infectious Diseases, 2020.
- Pan Y, et al. “ Viral Load of SARS-CoV-2 in Clinical Specimens.” Lancet Infectious Diseases, 2020.
- Patel R, et al. “Report from the American Society for Microbiology COVID-19 International Summit, 23 March 2020: Value of Diagnostic Testing for SARS–CoV-2/COVID-19.” mBio, 2020.
- Theravajan I, et al. “Breadth of concomitant immune responses prior to patient recovery: a case report of non-severe COVID-19.” Nature, 2020.
- Wang W, et al. “Detection of SARS-CoV-2 in Different types of Clinical Specimens.” JAMA, 2020.
- Wolfel, R. “Virological assessment of hospitalized cases of coronavirus disease 2019.” medRxiv, 2020.
- Xi, H, et al. “Temporal Dynamics in Viral Shedding and Transmissibility of COVID-19.” medRxiv, 2020.
- Yang Y, et al. “Evaluating the Accuracy of Different Respiratory Specimens in the Laboratory Diagnosis and Monitoring the Viral Shedding of 2019-nCoV Infections.” medRxiv, 2020.
- Zou L, et al. “SARS-CoV-2 Viral Load in Upper Respiratory Specimens of Infected Patients.” NEJM, 2020.