The importance of being immune to measles

Importance of being immune to measles

Measles is a serious and highly contagious disease. It makes most people very sick and can cause severe complications, including damage to the lungs (pneumonia), brain swelling (encephalitis), and sometimes death.  Measles also affects your immune system, so if you get measles you are more likely to get other infectious illnesses for months or years afterwards. 

Aotearoa New Zealand is at a very high risk of a measles outbreak. Measles cases are rising worldwide, increasing the risk of an infected person bringing measles into the country. This is happening while a decline in local childhood immunisation rates is being recorded. Across Aotearoa, people’s immunity to measles is currently too low to prevent outbreaks from happening.

A person can be infectious before they develop measles symptoms and know they are sick. So you may not know if or when you have been — or will be exposed to the disease.

Symptoms of measles(internal link)

This is why being immune to measles is important.

If you are immune and you are exposed to someone with measles:

• you will not get sick

• you will not be at risk of passing the illness on to anyone else

• you will not need to stay home in quarantine if public health identifies you as a close contact.

How to become immune to measles

You can become immune to measles in 2 ways:

• by having measles before

• by getting two doses of a measles vaccine after the age of 12 months. In Aotearoa, this is known as the combination measles, mumps, rubella (MMR) vaccine.

If you were born in Aotearoa New Zealand before 1969 it is likely you are immune to measles. This is because before this time there were no measles vaccines, so most people were infected with measles during childhood.

Checking if you are immune to measles

It is important to find records to confirm if you are immune to measles and not rely on your own or anyone else’s memory. This is because many viral illnesses can cause symptoms like measles, particularly in tamariki (children). In the past, people may have mistakenly been told they had measles when they had another illness instead.

It is also common for people to be told they received vaccines as a child, but without written records, no one can be sure what vaccines they received and when they received them.

In Aotearoa, the timing of when measles vaccines have been given to a person has changed a lot over the years. This means many people are not aware that they missed out on getting one or both of their measles vaccines. This is particularly likely for people born in Aotearoa between 1969 and 1980.

Measles immunity by year of birth (as at end of 2023) — Regional Public Health(external link)

To find out if you are immune to measles, you can check your relevant immunisation records or test results. Proof of this information is needed for a healthcare professional to confirm if you are immune.

Test results

Test results include either:

• a positive measles polymerase chain reaction (PCR) test taken via a swab to confirm a previous measles infection

• a blood test confirming the presence of measles antibodies indicating you are immune to measles.