Transmission
The highly contagious virus is spread by coughing and sneezing, close personal contact or direct contact with infected nasal or throat secretions. It can be transmitted by an infected person from 4 days prior to the onset of the rash to 4 days after the rash erupts.
Standard definition
Any person with fever 38°C or higher, generalised maculopapular rash lasting 3 or more days and/or cough, coryza, conjunctivitis and Koplik’s spots.
Laboratory diagnosis
Measles PCR is the test of choice from nasopharyngeal swabs. Measles virus is detectable from 3 days prior to rash onset to between 7-14 days after rash onset. The PCR can distinguish between wild-type and vaccine strain.
Measles IgG and IgM antibodies become positive 1-7 days after rash onset.
Positive Measles IgG with a negative Measles IgM is indicative of previous vaccination or infection.
Genotyping
Molecular epidemiology is used to complement and extend case and outbreak investigation. Respiratory or other samples from measles IgM positive cases are used for measles virus culture and molecular geneotyping (measles virus strain identification).
Quality Assurance
The WHO Measles IgM quality assurance program distributed by the VIDRL (Melbourne) is participated in annually.
The WHO Global Measles and Rubella Molecular eQA Proficiency Panel is participated in annually.
The RCPA Measles Quality Assurance Programme is participated in bi-annually.

Source: www.vidrl.org.au/labsandunits/measles
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