Non-specific defence

The body therefore has several non-specific defence systems. They are non-specific because they protect against many different pathogens rather than targeting one particular type.

Non-specific defences work against many kinds of pathogen: they do not need to recognise a particular one first. Some form barriers at the body's surfaces; others trap, remove or kill pathogens.

Several non-specific defences have acted in sequence before the pathogens can reach the blood.