measles

see also:

• viruses
• paediatric exanthems
• acute rashes in adults

• also called rubeola
• measles virus (MV), a negative-sense enveloped RNA virus, is a member of the Morbillivirus genus in the Paramyxoviridae family.
• measles is a highly communicable acute disease spread by airborne spread
• incubation period from exposure to onset of symptoms ranges from 8-12 days
• causes generalised immunosuppression which increases the risk of bacterial otitis media and bronchopneumonia.
  • resets the immune system back to an immature state like a baby's, with only limited ability to fight off new infections
• 0.1% develop acute encephalitis
• rarely, persistent measles infection may result some years later (mean 10.8 years) in subacute sclerosing panencephalitis (SSPE) which causes a chronic degenerative illness characterised by behavioral and intellectual deterioration, and seizures.
• approximately 30 million measles cases are reported annually. Most reported cases are from Africa
• measles caused an estimated 345,000 deaths worldwide in 2005 - 85% in Africa and South East Asia
• at the end of 2005, with the partnership of several global organizations, over 217 million children were vaccinated worldwide, reducing the number of deaths by 75% in Africa.
• highest fatality rates are among infants aged 4-12 months and in children who are immunocompromised because of human immunodeficiency virus (HIV / AIDS) infection or other causes
• risk factors for severe disease and its complications:
  • malnutrition
  • underlying immunodeficiency (eg. HIV / AIDS)
  • pregnancy
  • vitamin A deficiency
• measles-related mortality, most often due to respiratory and neurologic complications, occurs in 0.1-0.3% of reported US cases.

• those at risk (born after 1966 without vaccination):
  • children or adults born during or after 1966 who do not have documented evidence of receiving two doses of a measles containing vaccine or documented evidence of laboratory confirmed measles are considered to be highly susceptible to measles.
• clinical features:
  • high fever present at the time of rash onset
  • conjunctivitis, coryza, cough - onset usually precedes onset of rash by 3-7 days
  • Koplik’s spots - generally seen 2 days prior to the appearance of the rash and lasts until 2 days after the rash appears.
  • morbilliform (red blotchy) rash that generally begins on the face and spreads downwards before becoming generalised including palms/soles and lasts 5 days
    • desquamation and brown staining, which spares the palms and soles, may occur after one week
    • rash may be absent in patients with underlying deficiencies in cellular immunity
  • patients appear most ill during 1st 2 days of rash.
  • generalized lymphadenopathy, mild hepatomegaly, and appendicitis may occur because of generalized involvement of lymphoid tissue

• occurs in individuals who were vaccinated with the original killed-virus measles vaccine between 1963 and 1967 and who have incomplete immunity
• a mild or subclinical prodrome of fever, headache, abdominal pain, and myalgias precedes a rash that begins on the hands and feet and spreads centripetally. The eruption is accentuated in the skin folds and may be macular, vesicular, petechial, or urticarial. Koplik spots are common and last longer - usually 5-7 days;
• lab findings include eosinophilia and often LFTs are abnormal and CK may be raised
• CXR often shows nodular infiltrates, enlarged hilar lymph nodes +/- pleural effusion¹⁾
• The live-attenuated vaccine replaced the killed vaccine in 1967 and is not associated with atypical measles.

• patients need nursing in respiratory isolation, preferably in a negative pressure room
• be alert for new measles cases — make sure all staff, particularly triage nurses, have a high index of suspicion for patients presenting with a febrile rash illness, especially if associated with a preceding cough.
• triage nurse should notify senior medical officer immediately a person with suspected measles presents to ED.
• patient to don N95 mask and be triaged to with ATS urgency code 3
• avoid keeping patients with a febrile rash illness in waiting areas.
• isolate suspected cases within the department until a measles diagnosis can be excluded.
• if possible, move patient to a negative pressure room ASAP
• if no negative pressure room available, transfer to a consultation room where the door can be closed to limit airborne spread
  • this room should not be used for another patient until at least 2 hours after it has been vacated by the measles patient
• only persons who have been vaccinated against measles and/or were born before 1966 should care for the patient
• limit number of doctors and nursing staff involved with the patient
• assess by ED doctor as soon as possible and then liaise with hospital's Infectious diseases unit
• notify hospital Infection Control
• take blood for serological confirmation.
• send measles PCR nasopharyngeal swab and send to VIDRL marked as URGENT
• notify suspected measles cases immediately to the Communicable Disease Prevention and Control Unit on telephone 1300 651 160.
• if patient requires admission, admit to a ward with a negative pressure room
• if patient is well enough may be discharged after d/w ID but to stay at home pending confirmation

• ACT patient info sheet - measles
• ACT patient info sheet - measles contacts
• seek advice from DHS regarding the management of susceptible contacts:
  • on DHS advice, follow up all persons attending the Emergency Department at the same time as a case and for two hours after the visit. These people are considered to be exposed to the measles virus.
  • to prevent measles in susceptible contacts give EITHER:
    • MMR
      • if within 72 hours of first contact with the patient, and no known prior vaccination or measles infection, and not pregnant and normal immunity and age > 9 months old
    • NIHG Immunoglobulin
      • 0.2ml/kg to max 15ml by deep IM; or 0.5ml/kg if impaired immunity to max 15ml
      • if either:
        • longer than 72 hours but within 7 days from contact
        • within 72hrs if never has had a measles vaccine and has not been given MMR
        • C/I to MMR such as:
          • pregnant, non-immune
          • age 6 to 9 months
          • age 0 to 5 months if mother non-immune or is the index case
          • impaired immune system
          • allergy
      • NB. MMR should not be given within 5 months of NIHG injection
      • see also: ACT Health document on NIHG use in post-exposure measles cases (pdf)
• check your staff vaccination records:
  • all staff born since 1966 should have documentation of two doses of measles containing vaccine.
  • see DHS Health Care Worker Immunisation Policy