Overview
Measles, also known as ‘English measles’ or morbilli, is a potentially serious, highly infectious disease caused by a virus. It is one of the most infectious diseases in humans and the third most common vaccine-preventable cause of death among children throughout the world.
Measles epidemics are currently occurring in many regions of the world including the United Kingdom and the US. With New Zealand’s immunisation rates below what is required for elimination, there is a significant risk of an imported case of measles causing a large measles outbreak. Vaccination is the most effective form of prevention. All children over 12 months, adolescents and adults born on/after 1 January 1969 should be offered, or have documented evidence of, two doses of MMR/Priorix vaccine. MMR0 doses can be considered for children travelling overseas from 4 months of age.
For quick access to measles resources, click here
Introduction
Before a measles vaccine was developed, most people had caught measles in childhood. Universal vaccination was introduced in 1969 into New Zealand, although uptake of the vaccine had been low until recent years. New Zealand experienced two major measles epidemics in the 1990s which resulted in thousands of cases, hundreds of hospitalisations and seven deaths. The most recent major outbreak occurred in 2019/20 infecting more than 2000 people in New Zealand as well as spreading to Samoa where it caused 5705 cases and 83 deaths.
Measles epidemics are currently occurring in many regions of the world including the United Kingdom and the US. With New Zealand’s immunisation rates at an all-time record low there is a significant risk of an imported case of measles leading to another major outbreak. In particular measles immunisation rates for children <2 years have declined below protective levels and coverage is lowest for Māori and Pacific children and those from deprived communities. The virus is highly contagious amongst unimmunised people and young children and are at very serious risk from hospitalisation and long-lasting measles complications.
Transmission
Measles virus is highly contagious. It is spread through the air by infected droplets or by direct contact with secretions from the nose or throat of infected persons, for example by touching contaminated items or surfaces. It can survive for up to 2 hours in the air. A person with measles is most contagious from when symptoms start until three to four days after the rash appears. One person with measles can pass the disease on to 12–18 people who have not already had measles or been immunised against the disease.
Symptoms
It usually takes 10-12 days from exposure to the first symptom. 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.
Treatment
There is no specific antiviral treatment for measles. Supportive care including good nutrition, vitamin A supplements and adequate fluid intake, including hospital care when needed, can help to manage severe complications.
Risks
Complications from measles are common. The measles virus suppresses the immune system, lowering the body’s ability to fight other infections, for several years after infection. The risk of complications and death is greater in children under five years and adults over 20 years of age.
Common complications include ear infections, diarrhoea, and pneumonia. In New Zealand, more than 15 measles cases out of 100 are hospitalised. Pneumonia accounts for nearly two thirds of measles deaths.
Approximately 1 in 1000 cases develop encephalitis (inflammation of the brain), of these 15% die and approximately one third are left with permanent brain damage.
Several years after infection, 1 in 100,000 measles cases will develop subacute sclerosing panencephalitis (SSPE), a degenerative brain disease; this condition is always fatal.
Other complications include immune thrombocytopenic purpura (ITP), a problem of blood clotting, and inflammation of the small airways in the lungs, the heart, kidneys or liver.
Measles during pregnancy increases the risk of miscarriage and premature labour.
The risk of very serious disease is greatest for anyone with a weakened immune system. Such people are often unable to be immunised and rely on protection from those around them being immunised.
Death occurs in approximately 1 in 1,000 reported cases of measles, overall, in developed countries. Rates for death and disability are much higher than this in countries with poor nutrition and reduced access to good healthcare services.
Prevention
Vaccination is the best way to prevent measles. The vaccine currently available in New Zealand is Priorix: a combined measles, mumps, and rubella vaccine that contains weakened live viruses of all three diseases. The MMR vaccine is free for everyone in New Zealand under the age of 18. It doesn’t matter what your immigration status is. For those aged 18 years and over, the MMR vaccine is free if you’re eligible for funded healthcare in New Zealand. The vaccine is routinely offered on the National Immunisation Schedule at 12 month sand 15 months. However, early additional doses (MMR0) can be considered for children travelling overseas from 4 months of age (for screening and eligibility for MMR0 doses click here). It is important for all travellers to be immunised to prevent the risk of causing an outbreak in New Zealand upon return/arrival from overseas.
The vaccine is safe and effective but is contraindicated for certain people due to it being a live vaccine (see vaccine safety and information on contraindications here ). After the first dose of MMR vaccine, 90–95% of people will be protected against measles. After the second dose 97% of people will be protected. 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 and adults born after 1 January 1969, who do not have evidence of immunity against measles and have contact with infected cases are advised NOT to attend school, early childhood services or public places for 14 days after their last contact with the infected person or until advised by the local population health officers (or Medical Officer of Health).
More information on the vaccine, is available here on our Priorix webpage and here on the FAQ factsheet .
