There are multiple reasons why the world is still plagued by diseases we cannot treat or vaccinate against and the overall complexity of the human immune system is one of them - in fact, say Danish researchers, each of our immune systems has a unique code-like mechanism that prevents it from being deceived.

They have developed a method to expose this crucial part of the immune system's defense mechanisms which could lead to entirely new vaccines and treatments.

The researchers from BioCentrum DTU and the Faculty of Health Sciences at the University of Copenhagen have created models of neural networks which can simulate how the immune system defends itself from disease.

The neural network models indicate that the immune system's code-like mechanisms acts like a 'PIN code' for an ATM card. Every human being has its own unique immune system code, so even if a virus unlocks the code in one person, the knowledge gained by the virus cannot be used to infect the next individual.

That same defense mechanism makes it difficult to decode the entire human immune system and develop precise immunological treatments such as vaccines that can be generally manufactured and widely used.

Using their new neural network models, however, the researchers say they will be able to predict all the known codes - and also the as of yet unknown immune system PIN codes - meaning they can basically hack the immune system to get the immunization information needed for vaccinations.

So let's keep pesky 13 year olds away from that piece of code.