When collecting saliva specimens, utilize a polypropylene container with a wide opening such as a 50 mL centrifuge tube, specimen urine cup, or assembled funnel and collection tube. The collection container should be sterile, leak-proof, and, when possible, DNAse and RNAse–Free. Do not use any sampling containers that contain other extraction or stabilizing solutions.
Use PPE (Personal Protective Equipment) including disposable gloves, eye protection gear, a face mask, and lab coat during saliva specimen handling to minimize the risk of exposure to infectious viruses or unknown bacteria.
Subjects should avoid eating, drinking, smoking, chewing gum, brushing teeth, or rinsing with mouthwash at least 2 hours prior to sampling. Steroid inhalers, lotions, or creams such as hydrocortisone should not be used for at least 24 hours before collection. Instruct the subject to remove any dentures or removable orthodontic devices such as Invisalign or retainers and wash his/her hands.
To collect a saliva specimen:
- Instruct the subject to rinse his/her mouth with warm water for approximately 30 seconds. Wait a minimum of 10 minutes after rinsing to avoid sample dilution.
- Uncap the sterile specimen collection container and hand it to the subject. The subject should spit 1–2 mL of saliva into the specimen container and avoid touching the inside of the container or contaminating the outer surface of the container with saliva. Do not allow the subject to cough up sputum into the collection container as it may inhibit the specimen during RT-qPCR processing.
- Immediately cap the container after specimen collection is complete and perform a visual analysis. Discard the specimen if it is not clear or contains any blood.
Saliva specimens can generally be stored at 2–8 ˚C for up to 72 hours after collection and at -70 ˚C or below for long term storage.
Adhere to CDC Interim Guidelines for Collecting, Handling, and Testing Clinical Specimens for COVID-19 prior to specimen processing. For the packaging and transport of specimens, consult the current version of the International Air Transport Association (IATA) Dangerous Goods Regulation and follow shipping regulations for UN 3373 Biological Substance, Category B.
Do not reuse sample collection containers. Handle all containers as potentially hazardous waste and dispose of in accordance with local regulatory guidelines.