Measles (Rubeola) Overview

Measles (Rubeola)

What is Measles?
Measles is a highly contagious viral infection cased by a single stranded RNA Morbillivirus in the paramyxovirus family. The virus normally grows in the cells that line the back of the throat and lungs.

What are the Signs and Symptoms of this Illness?
Symptoms usually begin between 7 and 14 days after initial infection.

Common Symptoms:
Koplik's Sopts
  • Mild to Moderate Fever
  • Cough
  • Runny Nose
  • Sore Throat
  • Conjunctivitis (red/watery eyes)
  • Koplik's Spots (tiny white spots inside and around the mouth)
    Usually appear 2-3 days after first symptoms appear, may remain until 2-3 days after rash
    disappears.
    These occur in 60-70% of infections.
  • Blotchy Red or Red Brown Rash
    Usually appear 3-5 days after first symptoms
Rash usually begins at or near the hairline and spreads downward to the rest of the body. When rash appears fever may spike as high as 104°F. Rash may last as long as 5-6 days before beginning to fade.

Serious Symptoms:
Measles Rash
  • Ear Infection: 1/10
  • Pneumonia: < 1/20
  • Diarrhea*: 8/100
  • Blindness (Xerophthalmia)**: < 1/100
  • Encephalitis***:
    Acute Demyelinating Encephalitis: 1/1000
    Subacute Sclerosing Panencephalitis: 1/25,000
    Inclusion Body Encephalitis

Complications are most common in children under 5 years of age, and adults over 20. Individuals without adequate healthcare, who are suffering from malnutrition, a compromised or inferior immune system (from HIV or other diseases), or with a Vitamin A deficiency are at the highest risk over all.

*Diarrhea due to secondary bacterial or protozoal infections is common. This is particularly significant in malnourished individuals.

**Post Measles Blindness occurs in developing countries in approximately 1% of all infected children.
Xerophthalmia is caused by a severe Vitamin A deficiency which stops the eyes from producing tears. If left untreated, it can lead to corneal ulceration and blindness.
Treatments include artificial tears, increasing environmental humidity and wearing special glasses when outside. High dose Vitamin A supplements have been shown to inhibit progress of the condition. Once corneal ulceration takes place, eye surgery is the only option to return sight.

*** Three forms of Encephalitis are associated with this disease:
  1. Acute Demyelinating Encephalitis: Occurs within 2 weeks of the rash appearing, usually with seizures. Often accompanied by fever, irritability, headache, and changing consciousness. May progress to coma. It is believed to be a Neuro-allergic process. It carries a 10-15% mortality rate and 25% of survivors have permanent brain damage. Treatment is supportive with no clear benefit from Dexamethasone (an Antiinflamatory & Immunosuppressant Steroid)
  2. Subacute Sclerosing Panencephalitis: More common in boys where the initial infection occurs before age 2. Onset is usually between 5 and 10 years after an apparently normal measles recovery. Causes disturbance in intellect and personality, behavioral disorders and worsening school work. This is usually followed by seizures, signs of extrapyamidal and pyramidal disease (degenerative diseases that affect the brain & motor functions) and finally decerebrate rigidity (involuntary flexion or extension of arms & legs) and death. This condition is untreatable.
  3. Inclusion Body Encephalitis: Occurs in those with compromised immune systems, usually 1-7 months following exposure to Measles and is progressive over months. It is largely fatal, approximately 15% of survivors will have long term neurological complications.

    Long term Neurological Complications and Brain Damage Symptoms from Encephalitis may include:
  • Deafness
  • Seizure Condition
  • Mental Retardation

Average Total Infection & Recovery Time:
Infection to Recovery time varies greatly. From as little as 15 days, to as long as 28 days.

Death Rate & Causes:
Approximately 1-2 of every 1000 cases end in Death.

Respiratory or Neurological complications or both are most commonly noted as the primary cause of death in nearly 90% of cases.

In children under 5, death is most commonly attributed to respiratory problems. While deaths in the 10-14 year age range is most commonly caused by encephalitis or other neurologic complications.

Approximately 17% of individuals who die from Measles have some underlying disease at the time of death – this percentage increases with age.

How is this Illness Transmitted?
Airborne via respiratory droplets.
Virus can also remain transmissible for up to two hours on surfaces, removing the need for direct person to person contact.

Measles can not be carried by animals.

What is the Infectious Period?
From 4 days before, until about 4 days after the rash appears.

How Common Is This Illness?
United States:
An average of 60 cases are reported per year. However recent outbreaks have increased that number in recent years. In 2013, 189 cases were reported.

Worldwide:
An estimated 20 Million cases of Measles occur each year throughout the world.

What Treatments are Available and How Effective Are They?
There are no Measles Specific Treatments available. Any treatment given is for symptom relief only. The virus will run it's course in due time.

Vitamin A has been shown to help prevent eye damage and blindness. Vitamin A supplements have also been shown to reduce the number of deaths from measles by 50% in developing countries.

Sever complications can be avoided through good nutrition, adequate fluid intake, and treatment of dehydration when it occurs.

Eye & ear infections, as well as pneumonia can be treated with Antibiotics.


References:
  1. Centers for Disease Control: http://www.cdc.gov/measles/about/overview.html (2014)
  2. World Health Organization: http://www.who.int/mediacentre/factsheets/fs286/en/ (2014)
  3. American Journal of Diseases of Children (March 1975)
  4. Mishra A, Mishra S, Jain P, et al; Measles related complications and the role of vitamin A supplementation. Indian J Pediatr. 2008 Sep;75(9):887-90. Epub 2008 Jun 21: http://www.ncbi.nlm.nih.gov/pubmed/18568439
  5. Huiming Y, Chaomin W, Meng M; Vitamin A for treating measles in children. Cochrane Database Syst Rev. 2005 Oct 19;(4):CD001479: http://www.ncbi.nlm.nih.gov/pubmed/16235283

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