Every summer, in Australia, we always talk about sharks.

Well - we talk about fearing sharks.

In 2016, there were 2 fatal shark attacks in Australia.

In 2015 there were also 2, and 1 was provoked.

Sharks are a pretty common fear, but they attack us incredibly rarely, and mostly by accident.

Humans are pretty bad at understanding and managing risk.

Some things just sound scarier than they are, while other things sound too mundane to worry about.

But the truth is, just about everything in this world is trying to kill you.

Sorry, but, life is hard!

And we hear more about the rare and scary things than we do about the mundane things, building our irrational fears, and minimising our awareness of more common risks.

And it's important to know how to protect ourselves, both from the common stuff, and the rarer risks.

Spiders are a great example: over 30% or people are self-described arachnophobes.

Australia's funnel-web spider is considered the deadliest spider in the world, but there have been no confirmed deaths from funnel-web bites since the antivenom was invented in 1980.

Even the brown recluse spider in the US, another highly venomous arachnid, has only caused three recorded deaths.

Ever.

As scary as they seem, spiders are very unlikely to kill you.

Even bigger and louder things like lightning strikes cause fewer than 30 deaths in the US each year.

The real killers of the world are much more mundane.

Take transportation.

On average, about 500 people die in plane crashes worldwide every year, and that's one of the safest ways to travel.

Around the world, there are about 1.25 MILLION traffic fatalities each year.

Driving a car or motorcycle, biking, and walking, are all way more likely to kill you than flying, especially if you're not wearing a seatbelt, or you're distracted while on the road.

And CANCER is even more likely to kill you than your commute!

Each year, more than 8 million people die from cancer.

The cancer could be from smoking, pollution, alcohol consumption, diet, poor health, or just bad luck.

What's worse, as we get better at helping people survive spiders and sharks, and lightning, and car accidents, they live longer, and are more likely to get cancer.

Cancer rates are expected to increase by about 70% over the next 20 years, mostly due to people living longer, and long enough to get it.

This makes preventing cancer tough.

Even if you eat healthy, and don't smoke, and exercise regularly, you can still get cancer.

There are lots of ways to reduce your risks, but no solid, scientifically backed way to prevent it.

If there was, wouldn't you jump at the chance?

Over the past several hundred years, scientists have worked diligently to cure, prevent and treat deadly diseases, and one of the best tools is the vaccine.

We have vaccines for dozens of deadly diseases, including some types of cancer, and yet over 3 million people worldwide STILL die every year from vaccine-preventable diseases.

About half of those deaths are children under 5 years old.

There are a lot of things out there trying to kill you, your friends, family, and neighbours.

But if you get vaccinated, and you vaccinate your kids, there's one less big bad out there for you to worry about.

And maybe don't provoke a shark while you're swimming in a lightning storm.