The primary test for measles is a molecular test, specifically real-time reverse transcription polymerase chain reaction (RT-PCR). This test detects measles viral RNA in samples like nasopharyngeal and throat swabs, and urine. It's most effective when samples are taken early in the infection. Additional testing methods include serological testing, which checks for antibodies to the measles virus in the blood, indicating past infection or immunity.
Types of Measles Tests:
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Real-time RT-PCR: This is the most sensitive method for detecting active measles infection. It directly detects the measles virus's genetic material (RNA). As noted in the provided text, "Real-time RT-PCR uses nasopharyngeal, throat swabs, and urine specimens." (Reference: Real-time RT-PCR)
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Serological Testing: This test detects antibodies to the measles virus in a blood sample. It can indicate past infection or vaccination-induced immunity. The CDC's Measles Virus Laboratory provides this type of testing. (Reference: Laboratory Testing for Measles | Measles (Rubeola) | CDC) This method is less effective for diagnosing an acute infection compared to RT-PCR.
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Other specimen types: Throat or nasopharyngeal swabs are commonly used for testing. (Reference: Measles Laboratory Testing Guidance).
When is testing necessary?
Testing is recommended for individuals presenting with clinical features consistent with measles, including fever and rash. (Reference: Measles Laboratory Testing FAQS, Should I Test For Measles?) Laboratory confirmation is crucial for accurate diagnosis and to guide public health response. (Reference: Lab Testing for Measles at the MDH Public Health Laboratory) The purpose of testing can be either to diagnose a current infection or to determine immunity. (Reference: Measles and Mumps Tests: MedlinePlus Medical Test)
