Measles

  • Overview
  • In Depth
  • Vaccines
  • Video
Young child with measles

Measles is one of the most infectious diseases in humans. It is also known by the names English measles, morbilli and rubeola. Measles is now the third most common vaccine-preventable cause of death among children throughout the world.

A brief history

Before a measles vaccine was developed most people had measles by the age of 20. Universal vaccination was introduced in 1969 into New Zealand although the coverage of the vaccine has been poor until recent years. The last two major measles epidemics in NZ  occurred in the 1990s with thousands of cases, hundreds of hospitalisations and seven deaths. Smaller outbreaks continue to occur, mainly in communities where vaccine uptake has been low. Outbreaks tend to start when someone brings the disease back from an overseas trip.  As measles is extremely infectious it can spread very quickly.

NZ Situation

New Zealand continues to have outbreaks of measles, although at lower rates than previously. Due to higher immunisation rates in children by the age of two years outbreaks particularly affect unvaccinated older children, teenagers and adults.

Symptoms

The illness begins with fever, cough, runny nose and conjunctivitis (inflammation in the eyes), which lasts for 2-4 days. It may be possible to see small white spots (Koplik spots) inside the mouth. A rash appears 2-4 days after the first symptoms, beginning at the hairline and gradually spreading down the body to the arms and legs. The rash lasts for up to one week. It usually takes 10-12 days from exposure to the first symptom.

How do you get it?

Measles is spread through the air by infectious droplets or direct contact with secretions from the nose or throat of infected persons, for example by touching items or surfaces contaminated with secretions. The person with measles is most infectious during the first 2-4 days of symptoms and stays infectious until 3-4 days after the rash appears.

What are the risks?

Complications from measles are common. The measles virus suppresses the immune system, lowering the body’s ability to fight other infections.

Common complications include ear infections, diarrhoea, and pneumonia. In New Zealand more thatn 15 per 100 cases are hospitaised. Pneumonia accounts for nearly two thirds of measles deaths.

Approximately 1 per 1000 cases develop encephalitis (inflammation of the brain), of these 15% die and approximately one third are left with permanent brain damage.

One in 100,000 cases will,  years later, develop subacute sclerosing panencephalitis (SSPE, a degenerative brain disease). This condition is always fatal.

Other complications include immune thrombocytopenic purpura (ITP, affecting the blood clotting) and inflammation of the small airways in the lungs, heart, kidneys or liver.

The risk of complications and death are higher in children under 5 years and adults over 20 years of age.

Measles during pregnancy increases the risk of miscarriage and premature labour.

Anyone who has a weakness of their immune system is at greater risk of very serious disease. These people are often unable to be immunised and rely on protection from those around them being immunised.

Death occurs in approximately 1 per 1,000 reported cases of measles overall in western countries.

Who is the most at risk?

Anyone who has not received at least one dose of a measles containing vaccine e.g., the combined measles, mumps, rubella (MMR) vaccine or who has not already had the disease.

Treating the symptoms

There is no cure for measles infection.

Acute cases are treated with Vitamin A.

Preventing the disease from spreading

Immunisation given on time is the best way to prevent measles. Two doses of the MMR (measles, mumps, rubella) vaccine is 99% effective in preventing measles. MMR vaccine, if given within 72 hours of exposure to measles virus, may provide protection to the unimmunised and thus limit the spread of measles.
In the event of a measles outbreak unimmunised children (with no history of prior measles infection) who have contact with infected cases are advised NOT to attend school or early childhood services until notified.

Risk of disease vs. vaccine side effects
Measles Effects of disease Side effects of vaccine

Measles is a highly infectious viral disease that can often have serious complications.

  • Otitis media (ear infection): approximately 7-9 in 100.
  • Diarrhoea: approximately 8 in 100.
  • Pneumonia: approximately 6 per 100
  • Acute encephalitis (brain inflammation): approximately 1 per 1000
  • Subacute sclerosing panencephalitis (SSPE, a degenerative brain disease that is always fatal): 1 in 100,000.
  • The risk of complications and death are higher in children under 5 years and adults over 20 years of age and chronically ill.
  • Maternal measles increases risk for miscarriage and premature labour.
  • Overall death rate approximately 1 per 1000.
Common side effects
  • Approximately 6 per 100 have a mild to moderate fever
  • Approximately 2 per 100 have a rash or runny eyes
Uncommon side effects
  • Fever over 39.5 degrees Celsius less that 2 per 100.
Rare/very rare side effects
  • Anaphylaxis.
  • Temporary thrombocytopenia, approximately 1 per 30,000
  • Encephalitis may occur once in one million doses
  • Aseptic mumps meningitis in approximately 1 per 100,000

Measles is one of the most infectious diseases in humans. It is also known by the names English measles, morbilli and rubeola. Measles is now the third most common vaccine-preventable cause of death among children throughout the world.

Causative organism

Measles is a paramyxovirus, genus Morbillus. It is an RNA virus. Measles virus can survive for up to 2 hours in air, but is sensitive to heat, light and acidic pH.

Clinical signs, symptoms and complications

Early symptoms include fever, runny nose, cough, loss of appetite, and conjunctivitis or "pink eye." Characteristic white Koplik’s spots may occur in the oral mucosa.

After 3 to 5 days the rash appears at the hairline, moves to the face and upper neck, then proceeds down the body and usually lasts 4-6 days.

Measles is often a serious disease, with up to 30% of reported cases experiencing one or more complications.

Complications include:

  • Diarrhoea (8%), ear infections (7-9%) and pneumonia (1-6%), which accounts for nearly two thirds of measles-related deaths.
  • Acute encephalitis may develop in 1 in 1000 cases, of whom 15% die and a further 25% - 35% are left with permanent neurological damage.
  • Approximately 1 in 100,000 cases will develop subacute sclerosing panencephalitis (SSPE). This serious complication can lead to permanent brain damage.

Measles during pregnancy increases the risk of premature labour, miscarriage, and low-birth-weight infants, although birth defects have not been linked to measles exposure.

Measles can be especially severe in persons with compromised immune systems. Immunisation for household contacts is important to protect those who are immunocpmpromised.

The measles, mumps and rubella vaccine viruses are considered non-transmissable meaning they are not passed from the vaccine recipient to their contacts.

Method of transmission

Measles is one of the most contagious viral diseases and can be transmitted from four days before until four days after the appearance of the rash.

  • It is spread through the air by infectious droplets and is highly contagious.
  • It takes an average of 10-12 days from exposure to the first symptom, which is usually fever.
  • The measles rash doesn't usually appear until approximately 14 days after exposure, 3-5 days after the fever begins.
Public health significance

Measles is endemic globally, although a few countries with developed economies and high immunisation coverage have virtually eliminated wild measles virus.

  • Regular epidemics still persist in many countries.
  • Developing countries have a higher burden on morbidity and mortality from measles.
  • Measles has been earmarked as a candidate for elimination through the implementation of global mass immunisation programmes.
New Zealand epidemiology

Large scale measles epidemics occur when the number in the susceptible population increases and the immunisation coverage is low. It has been estimated that to prevent recurrent outbreaks of measles, 95 percent of the population must be immune. Since measles vaccine efficacy is 90–95 percent and not all children receive the first scheduled dose, the only way to achieve this level of immunity is by implementing a two dose immunisation strategy, as is now recommended. In 2000 a mathematical model was developed to estimate the future timing of measles epidemics in New Zealand. The results suggested that if no changes were made to the MMR schedule of 15 months and 11 years, the next measles epidemic would be between 2002 and 2004. Therefore from January 2001 the National Immunisation Schedule was changed to give the first dose of MMR at 15 months and the second dose at four years of age, prior to school entry. In 2005 the measles mathematical model was updated to calculate the effect of the measles catch-up in 2001 and to estimate the effect of changing the National Immunisation Schedule to give MMR at age 15 months and at age four years before school entry. As the incidence of measles decreases in New Zealand, it is important to continue high MMR immunisation coverage to lower the risk of imported measles causing outbreaks. Every suspected case of measles will need laboratory confirmation and characterisation to inform the local medical officer of health, so that public health control measures can be put in place.

Prevention

Measles is so highly infectious that immunisation is the only effective prevention.

Exclusion of cases from daycare, school and work, as well as exclusion of unimmunised individuals during an outbreak may reduce but not eliminate transmission.

If a child is exposed and has not been vaccinated, measles vaccine may prevent disease if given within 72 hours of exposure.

Immune globulin (0.6 mL/kg IM, to a maximum dose of 15 mL) may prevent or lessen the severity of measles if given within six days of exposure.

Measles vaccine is produced from a live attenuated (weakened) strain (Edmonston or Schwarz strains) of measles virus prepared in chick fibroblasts (embryo cell culture).

The attenuated measles vaccine virus undergoes the infectious cycle in the host, triggering an immune response and the development immunity.

M-M-R® II

MMR

M-M-R® II is used for primary vaccination and revaccination of children and adults to protect against measles, mumps and rubella.

Listed below are the available videos for this disease