Info for Laboratories about Coronavirus (COVID-19)


Revisions had been made on November 30, 2020 to mirror the next:

  • Added Nasopharyngeal (NP) and Nasal mid-turbinate (NMT) infographics to the Respiratory Specimens part.

Revisions had been made on November 3, 2020 to mirror the next:

  • Clarification on language for the gathering of anterior nasal specimens.

Revisions had been made on October 8, 2020 to mirror the next:

  • Clarification on language for the gathering of specimens and to incorporate the addition of saliva language.

Healthcare suppliers* and well being division workers contemplating ordering testing of individuals with attainable an infection of SARS-CoV-2 ought to work with their state, tribal, native, and territorial (STLT) well being departments to coordinate testing by public well being laboratories, or work with business or medical laboratories utilizing molecular and antigen checks. The kind of specimen collected relies on the check you’re utilizing and its producer’s directions. Among the specimen sorts listed under won’t be applicable for all checks.

CDC has steerage for who needs to be examined, however choices about who needs to be examined are on the discretion of STLT well being departments and/or healthcare suppliers. Testing for different pathogens by the supplier needs to be carried out as a part of the preliminary analysis, as indicated, however shouldn’t delay testing for SARS-CoV-2, the virus that causes COVID-19.

All SARS-CoV-2 check outcomes, together with positives, negatives and inconclusive findings, needs to be reported to the STLT well being division. Learn CDC’s Information and Reporting FAQ for Laboratories.

Scientific laboratories ought to NOT try viral isolation from specimens collected from folks suspected to have COVID-19 except that is carried out in a BSL-3 laboratory.

*Pharmacists are thought of healthcare suppliers on this steerage.

Specimen Kind and Precedence

All testing for SARS-CoV-2 needs to be carried out in session with a healthcare supplier. Specimens needs to be collected as quickly as attainable as soon as a choice has been made to pursue testing, whatever the time of symptom onset. The steerage under addresses choices for assortment of specimens.

For preliminary diagnostic testing for SARS-CoV-2, CDC recommends accumulating and testing an higher respiratory specimen. Please contact the testing laboratory to substantiate accepted specimen sorts. Please be aware that nasopharyngeal and oropharyngeal specimens will not be applicable for self-collection. The next are acceptable specimens relying on the approved SARS-CoV-2 viral check used:

  • A nasopharyngeal (NP) specimen collected by educated healthcare personnel; or
  • An oropharyngeal (OP) specimen collected by educated healthcare personnel; or
  • A nasal mid-turbinate swab collected by educated healthcare personnel or by a supervised onsite self-collection (utilizing a flocked tapered swab); or
  • An anterior nares (nasal swab) specimen collected by educated healthcare personnel, or self-collected and noticed by healthcare personnel, or by dwelling or onsite self-collection (utilizing a flocked or spun polyester swab); or
  • Nasopharyngeal wash/aspirate or nasal wash/aspirate (NW) specimen collected by educated healthcare personnel; or
  • A saliva specimen collected by the individual being examined, both at dwelling or at a testing web site beneath supervision.

Swabs needs to be positioned instantly right into a sterile transport tube containing 2-3mL of both viral transport medium (VTM), Amies transport medium, phosphate buffered saline, or sterile saline, except utilizing a check designed to research a specimen immediately, (i.e., with out placement in VTM), comparable to some point-of-care checksexterior icon. If VTM shouldn’t be out there, see the usual working process for public well being labs to organize viral transport mediumpdf icon in accordance with CDC’s protocol.

The NW specimen and the non-bacteriostatic saline used to gather the specimen needs to be positioned instantly right into a sterile transport tube.

Testing decrease respiratory tract specimens can be an choice. For sufferers who develop a productive cough, sputum will be collected and examined when out there for SARS-CoV-2. Nevertheless, the induction of sputum shouldn’t be advisable. When beneath sure medical circumstances (e.g., these receiving invasive mechanical air flow), a decrease respiratory tract aspirate or bronchoalveolar lavage pattern needs to be collected and examined as a decrease respiratory tract specimen.

Amassing and Dealing with Specimens Safely

For healthcare personnel accumulating specimens or working inside 6 toes of sufferers suspected to be contaminated with SARS-CoV-2, keep correct an infection management and use advisable private protecting gear (PPE), which incorporates an N95 or higher-level respirator (or facemask if a respirator shouldn’t be out there), eye safety, gloves, and a robe, when accumulating specimens.

For healthcare personnel who’re dealing with specimens, however will not be immediately concerned in assortment (e.g. self-collection) and never working inside 6 toes of the affected person, observe Normal Precautions. Healthcare personnel are advisable to put on a type of supply management (face masks) always whereas within the healthcare facility.

PPE use will be minimized by affected person self-collection whereas the educated healthcare personnel maintains at the very least 6 toes of separation.

Dealing with Bulk-Packaged Sterile Swabs Correctly for Higher Respiratory Pattern Assortment

Sterile swabs for higher respiratory specimen assortment could also be packaged in considered one of two methods:

  • Individually wrapped (most well-liked when attainable)
  • Bulk packaged

Bulk-packaged swabs could also be used for pattern assortment; nevertheless, care have to be exercised to keep away from SARS-CoV-2 contamination of any of the swabs within the bulk-packaged container.

  • Earlier than partaking with sufferers and whereas sporting a clear set of protecting gloves, distribute particular person swabs from the majority container into particular person sterile disposable plastic luggage.
  • If bulk-packaged swabs can’t be individually packaged:
    • Use solely recent, clear gloves to retrieve a single new swab from the majority container.
    • Shut the majority swab container after every swab elimination and go away it closed when not in use to keep away from inadvertent contamination.
    • Retailer opened packages in a closed, hermetic container to reduce contamination.
    • Preserve all used swabs away from the majority swab container to keep away from contamination.
  • As with all swabs, solely grasp the swab by the distal finish of the swab, utilizing gloved arms solely.
  • When sufferers are self-collecting their swabs beneath medical supervision:
    • Hand a swab to the affected person solely whereas sporting a clear set of protecting gloves.
    • The affected person can then self-swab and place the swab in transport media or sterile transport machine and seal.
    • If the affected person wants help, you may assist the affected person place the swab into transport media or a transport machine and seal it.

Basic Pointers

Correct assortment of specimens is an important step within the laboratory analysis of infectious ailments. A specimen that’s not collected appropriately could result in false destructive check outcomes. The next specimen assortment tips observe commonplace advisable procedures. For extra data, together with illustrations and step-by-step steerage, see the CDC Influenza Specimen Assortmentpdf icon directions. Observe that these directions are relevant for respiratory viruses normally, and never particular for less than influenza virus.

I. Respiratory Specimens

A. Higher respiratory tract

Nasopharyngeal specimen assortment /Oropharyngeal (throat) specimen assortment

Use solely artificial fiber swabs with plastic or wire shafts. Don’t use calcium alginate swabs or swabs with picket shafts, as they could comprise substances that inactivate some viruses and will inhibit molecular checks. CDC is now recommending accumulating solely the NP specimen, though OP specimen stay an appropriate specimen kind. If each NP and OP specimens are collected, they need to be mixed in a single tube to maximise check sensitivity and restrict use of testing sources.

Directions for accumulating an NP specimen: Tilt affected person’s head again 70 levels. Gently and slowly insert a minitip swab with a versatile shaft (wire or plastic) by the nostril parallel to the palate (not upwards) till resistance is encountered or the space is equal to that from the ear to the nostril of the affected person, indicating contact with the nasopharynx. Swab ought to attain depth equal to distance from nostrils to outer opening of the ear. Gently rub and roll the swab. Depart swab in place for a number of seconds to soak up secretions. Slowly take away swab whereas rotating it. Specimens will be collected from either side utilizing the identical swab, however it’s not crucial to gather specimens from either side if the minitip is saturated with fluid from the primary assortment. If a deviated septum or blockage create problem in acquiring the specimen from one nostril, use the identical swab to acquire the specimen from the opposite nostril.

For a visible information, see the Nasopharyngeal (NP) Specimen Assortment Steps infographic pdf icon.

OP specimen: Insert swab into the posterior pharynx and tonsillar areas.  Rub swab over each tonsillar pillars and posterior oropharynx and keep away from touching the tongue, tooth, and gums.

Nasal mid-turbinate (NMT) specimen

Use a flocked tapered swab. Tilt affected person’s head again 70 levels. Whereas gently rotating the swab, insert swab lower than one inch (about 2 cm) into nostril parallel to the palate (not upwards) till resistance is met at turbinates. Rotate the swab a number of instances in opposition to nasal wall and repeat in different nostril utilizing the identical swab.

For a visible information, see the Nasal mid-turbinate (NMT) Specimen Assortment Steps infographic pdf icon.

Anterior nasal (nares) specimen

Utilizing a flocked or spun polyester swab, insert all the absorbent tip of the swab (normally ½ to ¾ of an inch (1 to 1.5 cm) contained in the nostril and firmly pattern the nasal wall by rotating the swab in a round path in opposition to the nasal wall at the very least 4 instances. Take roughly 15 seconds to gather the pattern. You’ll want to gather any nasal drainage that could be current on the swab. Pattern each nostrils with similar swab.

For a visible information, see the How To Gather Your Anterior Nasal Swab Pattern For Covid-19 Testing infographic.pdf icon

Nasopharyngeal wash/aspirate or nasal wash/aspirate

Connect catheter to suction equipment. Have the affected person sit with head tilted barely backward. Instill 1 mL-1.5 mL of non-bacteriostatic saline (pH 7.0) into one nostril. Insert the tubing into the nostril parallel to the palate (not upwards). Catheter ought to attain depth equal to distance from nostrils to outer opening of ear. Start mild suction/aspiration and take away catheter whereas rotating it gently. Place specimen in a sterile viral transport media tube.


Gather 1-5 mL of saliva in a sterile, leak-proof screw cap container. No preservative is required.

B. Decrease respiratory tract

Bronchoalveolar lavage, tracheal aspirate, pleural fluid, lung biopsy

Gather 2-3 mL right into a sterile, leak-proof, screw-cap sputum assortment cup or sterile dry container.

Because of the elevated technical ability and gear wants, assortment of specimens aside from sputum from the decrease respiratory tract could also be restricted to sufferers presenting with extra extreme illness, together with folks admitted to the hospital and/or deadly circumstances.


Educate the affected person concerning the distinction between sputum and oral secretions (saliva). Have the affected person rinse the mouth with water after which expectorate deep cough sputum immediately right into a sterile, leak-proof, screw-cap assortment cup or sterile dry container.

Observe: That is an aerosol producing process and more likely to generate greater concentrations of infectious respiratory aerosols. Aerosol producing procedures doubtlessly put healthcare personnel and others at an elevated danger for pathogen publicity and an infection. Healthcare personnel ought to apply Normal Precautions and put on an N95 or equal or higher-level respirator, as a substitute of a face masks, eye safety, gloves, and a robe, when accumulating specimens.

II. Storage

Retailer specimens at 2-8°C for as much as 72 hours after assortment. If a delay in testing or transport is predicted, retailer specimens at -70°C or under.

III. Delivery

If crucial, and with advance approval, samples could also be shipped to CDC if repeated testing outcomes stay inconclusive or if different uncommon outcomes are obtained. Please contact CDC at previous to submitting samples to substantiate.

If transport samples to CDC: If specimens will ship at once, retailer specimens at 2-8°C, and ship in a single day to CDC on ice pack. If a delay in transport will lead to receipt at CDC greater than 72 hours after assortment, retailer specimens at -70°C or under and ship in a single day to CDC on dry ice. Further helpful and detailed data on packing, transport, and transporting specimens will be discovered at Interim Laboratory Biosafety Pointers for Dealing with and Processing Specimens Related to Coronavirus Illness 2019 (COVID-19).

Specimens have to be packaged, shipped, and transported in accordance with the present version of the Worldwide Air Transport Affiliation (IATA) Harmful Items Rules exterior iconexterior icon.

Label every specimen container with the affected person’s ID quantity (e.g., medical file quantity), distinctive CDC or state-generated nCov specimen ID (e.g., laboratory requisition quantity), specimen kind (e.g., serum) and the date the pattern was collected. Full a CDC Type 50.34 for every specimen submitted. Within the higher left field of the shape, 1) for check requested choose “Respiratory virus molecular detection (non-influenza) CDC-10401” and a pair of) for At CDC, deliver to the eye of enter “Unit 84 (Non-flu Resp Virus)”.

Please discuss with our instruction steerage for submitting CDC Type 50.34 discovered right here: Pointers For Submitting Specimens to CDCpdf icon.

For added data, session, or the CDC transport tackle, contact the CDC Emergency Operations Heart (EOC) at 770-488-7100.

Further Sources

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