Infectious diseases - immunity

The human immune systemimmune system
The body's natural defence mechanism against infectious diseases. is the body's natural defence mechanism against disease. It recognises and destroys pathogens inside the body. Pathogens, such as bacteriabacteria
Single-celled organism. Has a cell wall, cell membrane, cytoplasm. Its DNA is loosely-coiled in the cytoplasm and there is no distinct nucleus. and viruses, cause damage and disease when they reproduce and grow in number.

However, sometimes, our immune system takes longer or simply cannot identify and neutralise pathogens attacking our body. This is because our body has never been exposed to such pathogens, and therefore does not have defences ready to fight the infection.

Here is where vaccinationvaccination
The introduction of a small amount of dead or weakened pathogen into the body. It prepares the immune system to prevent future infections with the live pathogen. comes in. Vaccination is the process by which our body creates defences, or antibodies, to fight a pathogen by purposedly being exposed to a non-threatening inactive or dead version of the pathogen. Therefore, vaccination enables the body to respond more quickly to future infection by that pathogen.