Key points
- CDC recommends the collection and submission of samples for all suspected measles cases.
- Nasopharyngeal or throat swabs are preferred over urine specimens.
- Get information about collection, storage, and shipment of U.S. or international specimens.
Types of tests
Serology testing:
Detection of specific IgM antibodies in a serum specimens collected within the first few days of rash onset can provide presumptive evidence of a current or recent measles virus infection. Serology uses serum specimens.
Real-time RT-PCR:
Detection of measles RNA in a clinical specimen can provide laboratory confirmation of infection. Real-time RT-PCR has the greatest diagnostic sensitivity when specimens are collected at first contact with a suspected case. Real-time RT-PCR uses nasopharyngeal, throat swabs, and urine specimens.
Specimen collection
CDC's Infectious Diseases Laboratories provide guidance for various specimen collection, storage, and shipment, including for measles. Refer to the Infectious Diseases Laboratories Test Directory entry for each test.
Preferred specimens
CDC recommends that either a nasopharyngeal swab, throat swab, or urine specimen as well as a blood specimen be collected from all patients with clinical features compatible with measles.
Nasopharyngeal or throat swabs are preferred over urine specimens.
Submitting specimens
In addition to the information found on the CDC Infectious Diseases Laboratories Test Directory entry for each test, follow the guidance below for specimen collection and shipping. The instructions also include points of contact for the tests.
Contact health department first
Instructions for test types
Serologic testing
Collect the first (acute-phase) serum specimen as soon as possible upon suspicion of measles disease. If the acute-phase serum specimen collected ≤3 days after rash onset is negative, and the case has a negative (or not done) result for real-time RT-PCR (rRT-PCR), a second serum specimen collected 3–10 days after symptom onset is recommended. This is because the IgM response is not detectable in some cases until 3 days after symptom onset.
Measles RNA detection by RT-PCR
- Measles detection instructions (Test CDC-10543)
- Measles vaccine virus detection instructions (Test CDC-10528)
Detection of measles RNA is most successful when specimens are collected on the first day of rash through the 3 days following onset of rash. Detection of measles RNA by rRT–PCR may be successful as late as 10–14 days after rash onset.
Collect throat or nasopharyngeal swab specimens as soon as measles disease is suspected. rRT-PCR has the greatest diagnostic sensitivity when specimens are collected at first contact with a suspected case.
Specimen shipping to CDC
If instructed to send specimens to CDC from within the Unites States, you must download and complete the CDC Specimen Submission Form (50.34). Please fill out a form for each specimen submitted. Submitters are encouraged to use the CDC Specimen Test Order and Reporting (CSTOR) Web Portal to submit specimens.
Provide the following for domestic and international shipments:
- Contact name with telephone number and email address
- Case ID and specimen ID from the submitting laboratory associated with the specimen
- Type of virological specimen (throat swab, nasopharyngeal swab or urine), transport media (if applicable), and date collected
- Date serum specimen collected
- MMR vaccination history [date(s) if known]
- Clinical signs and symptoms
- Patient's date of birth or age
- Rash onset date
- Any previous test results (if known)
Shipping internationally
For international submissions, please contact Dr. Paul Rota, Dr. Bettina Bankamp, or Dr. Stephen Crooke.
For international shipments, refer to the Infectious Diseases Laboratories Test Directory entry for each test.
Programs
CDC Measles Virus Laboratory:
CDC's Measles Virus Laboratory provides serologic testing for measles as a national reference laboratory. It also provides technical assistance to state public health laboratories for the collection and shipment of clinical specimens for molecular diagnostics and genetic analysis. The Measles Virus Laboratory Team works closely with the Epidemiology Team to coordinate laboratory support for public health laboratories during outbreaks and investigations of suspected spread cases following an importation of measles.
The Measles Virus Laboratory acts both as a Regional Reference Laboratory within the laboratory network in the Region of the Americas (Pan American Health Organization) and as a Global Specialized Laboratory.
Methods and protocols for measles and rubella diagnosis and viral surveillance have been developed for the Laboratories in the WHO Global Laboratory Network.