Laboratory Testing for SARS

New York State Department of Health

Laboratory Testing for SARS-CoV at the Wadsworth Center

Patients must be reported to the local health department before specimens will be accepted at Wadsworth Center for SARS testing.

I. Which Specimens to Obtain

For the diagnosis of most viral respiratory pathogens like influenza and RSV, specimens should optimally be collected within 72 hours after the onset of symptoms. In contrast, the amount of SARS-CoV in respiratory specimens may be higher later in the course of the illness, peaking between days 10 to 14 post onset. Therefore, it is recommended that specimens be obtained as soon as possible for testing for alternative etiologies, as well as SARS-CoV. When possible, it is preferable to collect multiple specimens for testing. If no alternative etiology is found and the initial SARS tests are negative, additional respiratory, blood and stool specimens should be obtained between 7 and 10 days post onset and a convalescent serology should be obtained at >28 days post onset.

Upper Respiratory Tract

  • Nasopharyngeal wash/aspirate: Collect 1-2 ml from each nostril in sterile vials using non-bacteriostatic saline.
  • Nasopharyngeal or oropharyngeal swabs: Use only sterile dacron or rayon swabs with plastic shafts. Do NOT use calcium alginate swabs or swabs with wooden sticks.
    • Nasopharyngeal swabs - Insert swab into nostril parallel to the palate and leave in place for a few seconds to absorb secretions.
    • Oropharyngeal swabs - Swab both posterior pharynx and tonsillar areas, avoiding the tongue.

Place both swabs immediately into same sterile vial containing 2 ml of viral transport media. Break applicator sticks off near the tip to permit tightening of the cap.

Lower Respiratory Tract

  • Broncheoalveolar lavage, tracheal aspirate, pleural tap: Collect available fluid (at least 2ml) in sterile vials with external caps and internal O-ring seals. If there are no internal O-ring seals, then seal tightly with the available cap and secure with Parafilm®.
  • Sputum: Educate the patient about the difference between sputum and spit. Have the patient rinse the mouth with water then expectorate deep cough sputum directly into a sterile screw-cap sputum collection cup or sterile dry container.

Blood Components

  • Serum for antibody or RT-PCR testing: Acute serum specimens should be collected and submitted as soon as possible. If the patient meets the case definition, convalescent specimens should be collected >28 days after the onset of illness.

Collect 5-10 ml of whole blood in a serum separator tube. Allow blood to clot, centrifuge briefly and collect all resulting sera in vials with external caps and internal O-ring seals. If there are no internal O-ring seals, then seal tightly with the available cap and secure with Parafilm®. Label vials as containing serum with patient name, ID number and date collected. A minimum of 800 microliters of serum is preferred for each test.

Pediatric patients: a minimum of 1cc of whole blood is needed for testing. If possible, collect 1cc in both an EDTA and serum separator tube. However, if only 1cc can be obtained, please use a serum separator tube for collection, spin and remove serum prior to shipping.

  • EDTA blood/plasma for RT-PCR: Collect 5-10 ml of blood in an EDTA (purple-top) tube. Centrifuge briefly and collect all resulting plasma in vials with external caps and internal O-ring seals. If there are no internal O-ring seals, then seal tightly with the available cap and secure with Parafilm®. Label vials as containing plasma with patient name, ID number and date collected.

In order to provide the best quality specimen it is highly preferable to spin blood and remove serum or plasma prior to shipping. If it is not possible to spin blood specimens prior to shipping, ship in original collection tube sealed with Parafilm®.

Stool

Begin collecting stool specimens as soon as possible in the course of the illness. Place 10-50ml stool specimen, in a leak-proof tightly sealed stool cup or urine container. Patients may drape plastic kitchen wrap across the back half of the toilet, under the toilet seat, to facilitate collection of stool specimens. Refrigerate tubes after specimens are placed in them and ship immediately.

Tissue from surgical or autopsy specimens

As well as specimens described above, the CDC recommends collection of formalin fixed or paraffin embedded tissue from all major organs (lung, heart spleen, liver, brain, kidney and adrenals) and fresh frozen tissue from the lung and upper airway. Frozen tissue should be shipped on dry ice.

II. Forms to be submitted with specimens sent to Wadsworth Center

Three forms are required:

  1. Wadsworth Center Virus History Form.
  2. Informed Consent for the RT-PCR assay.
  3. Informed Consent for the EIA assay.

The RT-PCR and EIA assays have been released by the Food and Drug Administration (FDA) under an Investigational Device Exemption and are IRB-approved. Use of both assays requires completion of two informed consent documents, one each for the RT-PCR and EIA assays. The forms are available as at the following websites:
http://www.cdc.gov/ncidod/sars/lab/rtpcr/consent.htm and http://www.cdc.gov/ncidod/sars/lab/eia/consent.htm .

Note: If specimens have been collected prior to informed consent being obtained, the Patient Information Form may be completed instead of the RT-PCR and EIA informed consent forms. This form is available at www.cdc.gov/ncidod/sars/lab/rtpcr/participant.htm .

The completed forms MUST be shipped with the samples. Place the completed forms in a plastic bag on top of the outer shipping container but inside the outer cardboard box before sealing.

III. How to ship specimens to Wadsworth Center

  • Packaging, shipping and transport of specimens from suspect and probable SARS cases must follow the current edition of the International Air Transport Association (IATA) Dangerous Goods Regulations at http://www.iata.org/dangerousgoods/index and US DOT 49 CFR Parts 171-180 (http://hazmat.dot.gov/rules.htm)
  • It is essential that SARS specimens be sent to the Wadsworth Center as soon as possible after collection. If shipped within two days of collection, ship with cold packs to keep sample at 4ºC. Do not use wet ice. If shipment is delayed >2 days, then the specimens should be frozen and shipped on dry ice. Note: Whole blood should never be frozen or sent on dry ice.
  • All specimens must be shipped "Priority Overnight" and received within 24 hours via chosen carrier. Confirm that the selected carrier guarantees next day, morning delivery for diagnostic specimens.
  • Specimens should ONLY be shipped Sunday - Thursday so that appropriate laboratory personnel can be present to accept and accession specimens Monday - Friday. Samples should not be sent to arrive on a public holiday.
  • The Wadsworth Center Viral Reference and Surveillance Laboratory must be contacted via telephone or email prior to shipment. Please notify one of the following that you are shipping SARS specimens and provide patient initials and sample identification number.

Dr. Jill Taylor 518-862-4320, jxt07@health.state.ny.us
Dr. Norma Tavakoli 518-862-4323, npt02@health.state.ny.us
Mr. Ryan Bennett 518-869-4551, rtc03@health.state.ny.us

Samples should be shipped to:

Wadsworth Center, NYSDOH
Griffin Laboratory
Virus Reference and Surveillance Laboratory
5668 State Farm Road (Route 155)
Slingerlands, NY 12159

December 14, 2003