By Dr Eddy Bajrovic*
“Disneyland, the happiest place on Earth…”
So goes the famous marketing slogan. Well, not lately.
The famous theme park is ground zero for a growing outbreak of measles that began in December and as of last Friday had racked up 114 cases in 7 US states and 1 in Mexico. The outbreak likely started from a traveller who became infected overseas with measles, then visited the amusement park while infectious, according to the US Centres for Disease Control (CDC).
President Obama has weighed in on a raging public debate, urging unprotected Americans to get vaccinated as the national total passed 121 in 18 states this year.
The fact that Disneyland is at the centre of a measles outbreak isn’t surprising. Attracting thousands of visitors of all ages every day, it’s the perfect setting for this highly contagious virus to spread before jetting home across the globe with them.
But, unless they are lining up to meet Mickey or Goofy, why should Australians travelling overseas be concerned about measles?
Let me give you 6 reasons:
1 - Measles is one of the most infectious of all diseases
The lethal Ebola virus has dominated the news in the past year. Its basic reproductive rate is around 2: that is, each infected person will cause an average 2 new infections in susceptible individuals (i.e. those who are not immune because they were not vaccinated or were never exposed to the virus). In contrast, measles BRR is 15-18, and if you exposed 10 susceptible people to measles, on average 9 would be infected.
2 - The virus passes perfectly from one person to another
The measles virus lodges in the windpipe and replicates millions of times before causing coughing spasms that allow it be released into the air at head height and breathed in by unlucky passers-by. In a confined space, the invisible droplets can float suspended in the air for up to 2 hours – long after the infected person has left.
3 - It takes only one infected passenger…
As with flu, plane passengers at highest risk are those seated near the measles-infected person. But, get up to stretch your legs or go to the toilet and you could breathe in those virus-containing droplets in the air. Because they don’t always remember to cover their mouths, children are often the worst offenders in spreading measles.
4 - It is very common and occurs everywhere
Worldwide, around 20 million people get measles each year and outbreaks occur in developed and developing counties alike. While the US is concerned about 121 cases nationwide this year, German authorities are alarmed over 254 measles infections in January – mainly in Berlin. (It’s likely there were actually more cases: the German figures only include children.) Meanwhile, most of the 340 measles cases last year in Australia, which is officially measles-free, were directly or indirectly linked to overseas travel.
5- Even before you get sick, you could pass it on
The symptoms of measles – fever, runny nose, red and watery eyes, a cough, all-of-body rash – begin 7 to 21 days after exposure, but you become contagious around 4 days before the tell-tale rash appears and for 4 days after. You could inadvertently infect susceptible people you encounter – either on your return flight, or your family, friends, work colleagues and neighbours back home.
6 - Measles can make some people VERY sick
While most people recover fully from measles, some don’t. On average the virus kills 164,000 people – including 100,000 kids – each year. That’s 450 people every day, and unvaccinated babies under 6 months, pregnant women, and people with weakened immune systems are particularly vulnerable. As many as 1-in-20 children with measles gets pneumonia (the most common cause of measles deaths in young children), and 1-in-1000 will develop encephalitis that could leave them deaf or cognitively impaired. For every 1000 kids infected, 1 or 2 will die.
Travelling? Do the right thing
If that’s not bad enough, as well as being sick yourself, you won’t be popular with health authorities back home. Thousands of dollars will go into tracking down everyone on your flight, and alerting people at the airports and places you subsequently visited.
Ultimately, scores of people may be involved: their lives disrupted, their health impacted, precious health dollars wasted.
So, before you travel overseas, do the right thing by yourself, your loved ones, and your community by ensuring that you don’t bring home measles.
Check your immunisation status for measles and all of the childhood diseases, such as diphtheria, whooping cough, mumps, and polio – ideally 6 weeks before departure. These are among the routine immunisations that should be up to date – regardless of your age – although others may be recommended or even required for your overseas trip.
MMR vaccine is safe and effective
If you’ve had measles as a child, you can’t catch it again. If you haven’t, try to confirm that you’ve had 2 doses of measles-containing vaccine, such as the MMR (measles, mumps, and rubella) vaccine, in the past.
Australian immunisation guidelines recommend that travellers born during or since 1966 who have not received 2 doses of MMR vaccine should have at least 1 dose before departure and a second, final dose on their return.
The MMR vaccine is safe, effective, and provides long-term protection against all three diseases. (Protection against rubella is particularly important for women in their child-bearing years as infection just before conception or in early pregnancy could result in miscarriage, foetal death or congenital defects known as congenital rubella syndrome.)
Contrary to what you may read or heard, the MMR vaccine does not cause autism and is safe for children and adults who are allergic to eggs.
Beware post-travel fever with rash
Finally, if you or someone you travelled with develops a post-trip fever and rash, call your doctor and describe the symptoms over the phone.
Special arrangements will be made to see you privately to avoid infecting other patients, some of whom might be at risk of severe illness if they were to get measles.
Be sure to mention that you’ve travelled abroad.
By providing your travel history, you will help your doctor consider diseases that have become increasingly common among overseas travellers in recent years.
Like measles.
*Dr Bajrovic is Medical Director of Travelvax Australia.
Read more on measles and other routine vaccine-preventable diseases. For more pre-travel health advice, call Travelvax Australia no-obligation advisory service on 1300 360 164 (free from landlines).