In the year 2000, measles was eliminated! This was defined as absence of sustained transmission of the virus for more than 12 months. Unfortunately in 2019, 555 cases of measles have already been confirmed. The measles vaccine is 97% effective after 2 shots!
Epidemiology
Measles is one of the most contagious viral infections
Transmission is airborne, person to person via respiratory droplets. Droplets can hang in the air for about 2 hours!
Humans are the only natural host
The transmission rate from a patient amongst an exposed group of healthy individuals is about 90% in the absence of vaccination
The period of infectivity is typically 4 days prior to the onset of the rash and lasting up to 5 days following its appearance. The infectivity prior to the onset of rash is really important because patients are going to be infecting people before anyone really knows they’ve got an infectious disease
Signs and Symptoms
Incubation period is 10-14 days then you get a prodrome of high fever and URI symptoms along with the 3 C’s. Cough, coryza and conjunctivitis, these appear 2 – 4 days before the rash.
Rash is described as Erythematous maculopapular-to-confluent and starts up top (forehead and behind ears) then spreads downward.
Measles Complications
Pneumonia – the leading cause of measles-related deaths
Keratoconjunctivitis (Measles can exacerbate vitamin A deficiency and lead to blindness)
Acute Disseminated Encephalomyelitis (ADEM) and Measles Inclusion-Body Encephalitis – these result in permanent brain damage
Subacute Sclerosing Panencephalitis (SSPE) is a degenerative disease of the brain caused by measles, that can occur 7 – 10 years after measles virus infection.
Mortality: Two of every 1000 children infected with measles will die from respiratory or neurologic complications
Clinical Keys
Febrile patient? Ask about their vaccination status and exposures and consider testing
Fever and rash? ISOLATE. Ask about vaccination status, where they live and remember to keep isolated while you test if you suspect measles
Testing
IgM antibody in serum and measles RNA by real-time polymerase chain reaction (RT-PCR) from a throat swab (or nasopharyngeal swab).
Urine samples may also contain virus and when feasible, collect both a respiratory and urine sample to increase the likelihood of detecting the virus.
Management
There is no specific antiviral for Measles so treatment is supportive.
If severe disease in children treat with vitamin A for prevent of keratoconjunctivitis.
50,000 IU for infants younger than 6mos of age
100,000 IU for infants 6 – 11 months of age
200,000 IU for children 12 months of age and older
