Can You Catch Cancer? You Can, If You’re a Tazmanian Devil.

In humans, cancer is not something you can catch. Cancer is a disease where your own cells divide and grow out of control. This underlies one of the major divisions between types of diseases: communicable and non-communicable diseases.

Two different types of communicable pathogens under a Gram's Stain.

Communicable disease are usually caused by a pathogen, something nasty that gets in your body and makes you sick. Pathogens can be things like bacteria, viruses, fungi, and other things. The thing that they have in common is that they are caused by an infection. This infection is something that uses you to reproduce and pass to someone else.

Non-communicable diseases don’t communicate

You can’t catch a non-communicable disease because they aren’t caused by a pathogen. They are caused by something in your body breaking. Many examples of this include genetic diseases.

This girl has down's syndrome, caused by a genetic abnormality.

A disease like Down’s syndrome isn’t communicable because it is something deficient in the cells; you can’t pass that on.

Normally, cancer is non-communicable

Cancer happens when your cells forget to stop dividing. Your normal cells like to divide only as much as they need to. This can just happen when your cells get old; usually its not caused by something else. Though this is bad, it also means that you can’t catch someone’s cancer: you only get cancer when your own cells go bad.

The pink in the middle is cancer (squamous cell carcinoma). These cells used to be just like the normal cells next door.

Tazmanian Devil Cancer: trasmitted through bite

The wily cartoon Taz is a tazmanian devil. He (and his real counterparts) were beginning to die of a mysterious disease.

It turned out that, one tazmanian devil got a very aggressive tumor. These cells were able to grow and divide very fast. When this first animal took a bite at another of his friends, a couple of the tumor cells came along with the bite. Because they grow so well, they set up shop in the bite wound. Then this guy bites another; the cycle continues.

Cancer evolution plays by its own rules

This is a pretty spooky thought. We already know that cancer sometimes does some wacky things with natural selection. Could something like this happen with a human tumor cell? What would we do if it did? Leave a comment below to tell me what you think.

(bacteria photo credit: kaibara87; girl photo credit javier delgado esteban; cancer photo credit: Pulmonary Pathology; taz photo credit: mlvn.snmgl; tazmanian devil photo credit: Richard.Fisher)