Australians are being urged to check their immunisation history as the number of measles cases in the country climbs towards a five-year high.
- A sharp increase in measles cases has prompted Government immunisation warnings
- Individuals born between 1966 and 1994 and those planning to go overseas are at higher risk
- Measles is a highly infectious disease that requires high vaccination rates to stop its spread
Nationally, there have been 92 confirmed cases of measles so far this year, compared to 103 for the whole of 2018, and 81 for the whole of 2017.
Just five years ago, Australia was declared measles-free, and high vaccination rates have meant the virus has been largely kept at bay.
However, because it is so highly infectious, measles outbreaks occasionally happen when people travelling overseas catch the infection and bring it back into Australia, said Kristine Macartney, director of the National Centre for Immunisation Research and Surveillance.
“Globally, we’re seeing hundreds of thousands of cases of measles, and indeed tens of thousands of measles deaths,” Professor Macartney said.
“Measles is incredibly contagious, and where there are not very high vaccination rates — over 90 per cent — we are at risk of seeing it rear its ugly head.
“Unfortunately, that’s what’s happening around the world at present … it is quite a serious situation.”
How do measles spread?
Measles is a highly contagious viral illness — it spreads through coughs and sneezes.
But it’s not just spluttering that will pass it on. The measles virus can survive on surfaces for up to two hours, meaning you can catch it by touching the same surfaces or breathing in the same air as an infected person.
Measles is so contagious that about nine in 10 people who come in contact with the virus will catch it if they are not immunised.
It typically takes 10 days between a person being exposed to the virus and becoming sick, which is also when they become contagious.
Early symptoms of measles include fever, a cough, sore throat, runny nose, watery eyes, and feeling tired. About four days after the first symptoms appear, a rash will emerge.
But it’s not that serious, right?
For most people, a case of measles usually means taking a couple of weeks of bed rest, plenty of fluids, and some paracetamol to ease the pain and fever, before they make a full recovery.
Occasionally, however, measles can lead to serious and sometimes fatal complications, including:
- Middle ear infection
- Diarrhoea and vomiting (which may cause dehydration)
- Pneumonia and other respiratory infections
- Problems for pregnant women
- Swelling of the brain
According to the Department of Health, about 1 in 15 people infected with measles gets pneumonia, and 1 in 1,000 develops brain swelling, which can lead to brain damage or death.
It’s also possible for a person, many years after a measles infection, to develop a devastating and disabling brain disorder known as subacute sclerosing panencephalitis, which is fatal.
In 2017, there were 110,000 measles deaths globally, mostly among children under the age of five.
I think I’m immunised…
In Australia, children routinely receive two doses of the measles-mumps-rubella vaccine (MMR) — once at 12 months, and again at 18 months. Two doses are recommended for full protection.
While vaccination rates are high among children — 93.5 per cent of 2-year-olds have received two doses of the MMR vaccine — Professor Macartney said many Australians aged in their 20s to early 50s (born between 1966 and 1994) may not be fully vaccinated.
“That second dose of the measles vaccine wasn’t routinely given until the early 90s … so people may think they’ve had the two recommended doses, when actually they haven’t,” she said.
The two-dose vaccination program was introduced in Australia in 1992 and school-based programs provided children with catch-up vaccinations until 1998 (at which point it was routine).
But Professor Macartney said many Australians born earlier may have missed out on the second dose, or indeed missed out on the measles vaccine altogether.
“We know that in the 1980s and early 1990s, for example, our immunisation rates were as low as 70 per cent,” she said.
“So, for people who were children in the 80s and are now in their 30s, they may not have been vaccinated at all against measles.”
Australians born before 1966 don’t have to worry, she said. They’re likely to have natural immunity to the virus because of how widely it was circulating prior to the introduction of the national vaccination program.