Measles

• What is measles?

  Infectious disease caused by Measles morbillivirus (paramyxovirus)

  Transmitted via droplets from infected persons' nose, mouth, or throat

  Very contagious
• What is the incubation period of measles?


  10-14 days
• Pathophys - measles


  RNA paramyxovirus -> spread via droplets from infected person

  Virus infects epithelial cells of nose & conjunctivae -> multiplies in cells & extends to regional lymph nodes

  Primary viraemia (2-3 days after infection) -> virus continues to replicate in epithelial & reticuloendothelial system tissue

  Secondary viraemia (days 5-7) -> infection becomes established in skin & other tissues

  
  

  Infection from prodrome until 4 days after rash starts

  Incubation period = 10-14 days
• What are the signs & symptoms of measles?

  Prodromal symptoms

  • high fever (> 40)
  • coryzal symptoms
  • conjunctivitis

  Koplik spots (small grey/white discolourations of mucosal membranes in mouth, appear 1-3 days prodromal symptoms)

  Rash (appears 2-5 days after onset of prodromal symptoms) - first appears behind ears, then spreads down trunk to limbs over 3-4 days
• What is shown in the image?

  Measles rash (maculopapular rash)

  
• What is shown in the image?

  Koplik spots (in measles)

  
• What are the DDx of measles?


  Rubella (often milder than measles, rash typically starts on face & spreads to rest of body)

  Roseola Infantum (sudden high fever followed by rash, starts on chest, back & abdomen)

  Scarlet fever (sandpaper-like rash, high fever & sore throat, tongue may become red & bumpy)
• What are the investigations for measles?


  Obs

  Full Hx & examination

  Oral fluid samples (for measles RNA & measles-specific IgM & IgG)

  If oral fluid samples are not available -> serum & mouth swab used

  • Measles-specific IgM & IgG (most sensitive 3-14 days after onset of rash)
  • Measles RNA detected by PCR (most sensitive 1-3 days after onset of rash)
• Measles is a notifiable disease.
• What is the management of measles?


  Supportive care (antipyretics & adequate fluid intake)

  Vitamin A administration (recommended by WHO)

  Child must remain off school until at least 4 days after the development of the rash

  Should be advised to avoid pregnant women or immunosuppressed individuals

  Management of contacts

  > MMR vaccine

  > should be given within 72 hrs
• How can measles be prevented?


  MMR vaccinations in routine child immunisations

  If have been in contact with patient infected with measles -> seek advice of public health (> 1 yr or immunosuppressed children may require immunoglobulin treatment)
• What are the possible complications of measles?


  Acute otitis media

  Bronchopneumonia

  Encephalitis

  Diarrhoea

  Keratoconjunctivitis & blindness

  Increased opportunistic infections months following measles

  Subacute sclerosing panencephalitis (SSPE)-> rare but important complication of measles
• What is subacute sclerosing panencephalitis (SSPE)?


  Degenerative disease causing cognitive, motor and behavioural decline resulting, ultimately, in death

  Can occur any time after infection, commonly it is after 7 yrs
• Symptoms of measles usually develop 10-14 days post-exposure & lasts for 7-10 days.
• What is the most common complication of measles?

  Otitis media