Measles usually starts with a 2-4 day prodromal illness with fever, cough, coryza, and conjunctivitis.
A maculopapular rash then typically begins on the face and neck and becomes generalised. The fever is usually still present at the onset of the rash.
Measles in previously vaccinated people may present atypically, often with milder symptoms and a slower progression to the rash.
Cases are infectious from the day before the prodrome to four days after the rash onset.
Koplik spots may also be seen - small spots with white or bluish white centres on an erythematous base, on the buccal mucosa.
Common complications from measles include otitis media, pneumonia, and bronchitis.
Measles can cause serious illness requiring hospitalization, even in previously healthy children and adults,.
Severe respiratory and neurologic complications, including encephalitis, occurs in one to three out of every 1,000 children, and can be fatal.
Subacute sclerosing panencephalitis (SSPE) is a rare but fatal degenerative disease of the central nervous system characterized by behavioural and intellectual deterioration and seizures, which generally develop 7 to 10 years after measles infection.
Two doses of a measles-containing vaccine confers protective immunity in 99% of recipients. Measles outbreaks typically include both unvaccinated and under-vaccinated individuals (i.e. received only one vaccine dose).
People born prior to 1966 are generally assumed to be immune to measles following natural infection.
For people born in 1966 or later with no history of measles infection, evidence of protection requires documented evidence of receiving two doses of vaccine, not just from patient or parental recall.
Immunisation programs in Australia from the late 1960's included only one measles vaccine dose. A second dose was introduced in the 1990's so many people will have had only one dose.
Public health unit staff can help check for measles vaccination records on the Australian Immunisation Register (AIR) and the school immunisation database. Call 1300 066 055.
If measles protection is uncertain it is safe to give another measles vaccine dose provided there are no contraindications (such as immunosuppression or pregnancy).
Measles vaccination causes a rash to occur in 2–5 per cent of vaccinees. The rash typically occurs 7–10 days after vaccination and lasts about 2 days.
Measles testing is not required unless the patient has also been exposed to a measles case. In these circumstances a nasopharyngeal swab and urine should be collected and referred to NSW Pathology West - ICPMR or NSW Pathology South - SEALS where PCR testing can distinguish between wild and vaccine-type measles strains.
Consider measles in returning travellers with fever, and in anyone with fever and a maculopapular rash.
Measles remains endemic in many parts of the world, including destinations popular with Australian travellers.
Measles is no longer endemic in Australia but susceptible people can still be exposed to infected visitors or returned travellers.
Discuss vaccination with your patients – consultations prior to overseas travel are opportunities to encourage measles vaccination for any patients with uncertain vaccination histories.
Children aged from 6 months to under 12 months can have an MMR vaccination early if travelling overseas (they will still need their routine doses at 12 and 18 months of age).
