Specimens for measles PCR should be obtained within five days of rash onset (0-9 days max). Viral RNA is more likely to be detected when the specimen is collected as soon as possible after rash onset.
Specimen Types Vary:
- On day 0-5 of rash, collect a throat swab*
- On day 6-9 of rash, collect a throat swab and a urine specimen**
*If a throat swab cannot be collected, a nasopharyngeal specimen can be sent instead; however, a throat swab is the preferred specimen IF case is clinically compatible and reports an exposure to measles or has had recent travel, attempt collection of all three specimens (throat, nasal and urine).
**If date of specimen collection is already more than nine days past rash onset, PCR is not valid.
A throat swab is preferred. Nasal/NP swabs or washes are acceptable but not preferred.
Throat swab: Swab tonsillar areas and posterior nasopharynx. Use tongue blade to depress tongue to prevent contamination of swab with saliva. Place swab into 2-3 ml of viral transport media. (Same as the SHL flu kit)
Urine specimen: Collect 10-40 ml of urine in a sterile urine specimen container. Have patient void directly into container, collecting from the first part of the urine stream if possible. First-morning voided specimens are ideal, but any urine collection is adequate.
Appropriate swabs and media:
- Dacron swabs, flocked swabs
- Viral transport medium (VTM)
- Wood-tipped applicators, Cotton-tipped swabs, Calcium-alginate tipped swabs, Charcoal swabs, Gel swabs
- Dry swabs are not acceptable
Ship specimens on cold packs.