hot & spotty #2…

Measles.

The most common vaccine-preventable cause of death among children.

Epidemiology.

• A highly contagious, endemic viral infection.
  • Single-stranded RNA paramyxovirus.
• Peak incidence: Winter to Spring.
  • Transmission via respiratory droplets.
• Rare in infants < 6-8 months (2* maternal antibodies)
• Incubation period ~ 10 days (post exposure)
• Infectious period:
  • 1-2 days before prodrome
  • ~ 4 days after rash appears.

The Vaccine.

• MMR vaccine. Two-dose schedule.
• Decreased by 99% since vaccine introduction in the 60’s.
  • > 95% immunity required to prevent epidemics.

Clinically.

• Prodrome ~ 3-4 days.
  • High fevers & URTI symptoms.
    • “Cough, coryza & conjunctivitis”
  • Associated malaise, photophobia, eyelid oedema & myalgias.
• Exanthem develops ~ 14 days post-exposure.
  • Centrifugal pattern: central to peripheral.
  • Hairline –> face –> chest –> abdomen –> feet.
  • Reddish-brown, erythematous maculopapular rash –> confluence (morbilliform).
  • May have desquamation during healing phase.
  • Resolves within 6-7 days.
• Koplik spots (seen above).
  • Pathognomonic exanthem.
  • ~1mm white lesions (with bright red base) on buccal mucosa, opposite lower molars.
  • Present 1-2 days prior to rash.

• Rubella
• Scarlet Fever
• Enterovirus
• Roseola
• Erythema Infectiosum (“slapped cheek”)
• Kawasaki disease

• Measles IgM.
  • If positive –> confirms disease.
  • Detectable for ~ 1 month after rash onset.
• Viral culture.
  • from nasopharynx, blood or urine.

Meningoencephalitis / Encephalomyelitis.

• 1:1000 cases.
• 40% die or have severe neurologic injury.
• Symptoms:
  • Ataxia, agitation, vomiting & seizures.

Subacute sclerosing panencephalitis.

• a progressive neurodegenerative disorder
• behavioural disturbance, myoclonus, seizures, pyramidal signs…
• Thankfully RARE.
  • ~5:100,000 cases.
• 2-10 years after measles infection.
• Fatal in 1-3 years.

Others.

• Leukopenia
  • < 2000 is a marker of poor prognosis
• Thrombocytopenia
• Jaundice (rare)
• Bronchiolitis
• Pneumonia (+ giant cell pneumonia)
• Croup
• Cervical adenitis
• Myopericarditis

• Supportive care.
• Vitamin A.
  • Increased morbidity/mortality with Vitamin A deficiency
  • Consider in children 6-24 months (needing admission).

• Isolate all suspected cases as soon as they are identified
• Maintain standard & airborne precautions.
• If staff have no prior immunity, vaccine provides permanent protection & may prevent disease if given within 72 hours of exposure.
  • 0.25mL/kg (max 15mL)
  • Preferable to IG (which can be given up to 6 days post-exposure), as this immunity is temporary.
• All suspected cases MUST be reports to Public Health for contact tracing etc.

“Do we need to keep the kids away from her ?” Mum asks…

The short answer is YES !!

Risk to Pregnant Females.

• Exposure can lead to miscarriage, premature labour or stillbirth.
• Consider use of measles immunoglobulin.
  • Does not prevent complications, but may attenuate disease severity.
• Do NOT have MMR vaccine if you are already pregnant.

If in doubt, the auntie should see her GP as soon as possible.

1. Tintinalli’s Emergency Medicine: A Comprehensive Study Guide. 7th Edition.
2. Rosenʼs Emergency Medicine. Concepts and Clinical Approach. 7th Edition.
3. PEMsoft “Measles (Rubeola)” via CIAP