Measles

Measles is a highly contagious acute viral infection, transmitted by the airborne route (inhalation of respiratory droplets spread by infected individuals). The disease mainly affects children under 5 years of age and can be prevented by immunization.

For more information, refer to the guide Management of a measles epidemic, MSF.

Clinical features

The average incubation period is 10 days.

Prodromal or catarrhal phase (2 to 4 days)

• High fever (39-40 °C) with cough, coryza (nasal discharge) and/or conjunctivitis (red and watery eyes).
• Koplik’s spots: tiny bluish-white spots on an erythematous base, found on the inside of the cheek. This sign is specific of measles infection, but may be absent at the time of examination. Observation of Koplik's spots is not required for diagnosing measles.

Eruptive phase (4 to 6 days)

• On average 3 days after the onset of symptoms: eruption of erythematous, non- pruritic maculopapules, which blanch with pressure. The rash begins on the forehead then spreads downward to the face, neck, trunk (second day), abdomen and lower limbs (third and fourth day).
• As the rash progresses, prodromal symptoms subside. In the absence of complications, the fever disappears once the rash reaches the feet.
• The rash fades around the fifth day in the same order that it appeared (from the head to the feet).

The eruptive phase is followed by skin desquamation during 1 to 2 weeks, very pronounced on pigmented skin (the skin develops a striped appearance).

In practice, a patient presenting with fever and erythematous maculopapular rash and at least one of the following signs: cough or runny nose or conjunctivitis, is a clinical case of measles.

Complications

Most measles cases experience at least one complication:

• Respiratory and ENT: pneumonia, otitis media, laryngotracheobronchitis
• Ocular: purulent conjunctivitis, keratitis, xerophthalmia (risk of blindness)
• Gastrointestinal: diarrhoea with or without dehydration, benign or severe stomatitis
• Neurological: febrile seizures; rarely, encephalitis
• Acute malnutrition, provoked or aggravated by measles (post-measles period)

Pneumonia and dehydration are the most common immediate causes of death.

Case management

• Admit as inpatient children with at least one major complication:
  • Inability to eat/drink/suck, or vomiting
  • Altered consciousness or seizures
  • Dehydration
  • Severe pneumonia (pneumonia with respiratory distress or cyanosis or SpO₂ < 90%)
  • Acute laryngotracheobronchitis (croup) a Citation a. Symptoms (hoarse crying or voice, difficulty breathing, a high-pitched inspiratory wheeze [inspiratory stridor], characteristic "barking" cough) are caused by inflammation and narrowing of the larynx. Croup is considered benign or “moderate” if the stridor occurs when the child is agitated or crying, but disappears when the child is calm. The child should be monitored during this period, however, because his general and respiratory status can deteriorate rapidly. Croup is severe when the stridor persists at rest or is associated with signs of respiratory distress.
  • Corneal lesions (pain, photophobia, erosion or opacity)
  • Severe oral lesions that prevent eating
  • Acute malnutrition
• Treat as outpatient children with no major complications, no complications or minor complications:
  • Pneumonia without severe signs
  • Acute otitis media
  • Purulent conjunctivitis (no corneal lesions)
  • Diarrhoea without dehydration
  • Oral candidiasis that does not interfere with eating

If in doubt, keep the child under observation for a few hours.

• Isolation
  • Isolation of hospitalized patients
  • Measles cases treated as outpatients should be kept at home during this period.

Treatment

Supportive and preventive treatment

• Treat fever: paracetamol (Fever, Chapter 1).
• Make the child drink (high risk of dehydration).
• Give smaller, more frequent meals or breastfeed more frequently (every 2 to 3 hours).
• Clear the nasopharynx (nose-blowing or nasal lavages) to prevent secondary respiratory infection and improve the child’s comfort.
• Clean the eyes with clean water 2 times daily and administer retinol on D1 and D2 (see Xerophthalmia, Chapter 5) to prevent ocular complications.
• In children under 5 years: amoxicillin PO for 5 days as a preventive measure (reduction of respiratory and ocular infections).
• In the event of watery diarrhoea without dehydration: oral rehydration according to WHO Plan A (see Dehydration, Chapter 1).
• Insert a nasogastric tube for a few days if oral lesions prevent the child from drinking.

Treatment of complications

Prevention

• No chemoprophylaxis for contacts.
• Vaccination:
  • Between 9 and 12 months: one dose of 0.5 ml. The WHO recommends a second dose between 15 and 18 months. Respect an interval of at least 4 weeks between doses.
  • Where there is high risk of infection (overcrowding, epidemics, malnutrition, infants born to a mother with HIV infection, etc.), administer a supplementary dose from 6 months of age then continue vaccination schedule.
  • Children under 15 years who have missed either one or both doses of routine vaccination should be vaccinated when they come in contact with health services. Check national recommendations.