Quicker upon secondary exposure Develops memory
Is it BIG?
Is it SMALL?
Is it INSIDE (intracellular)?
Is it OUTSIDE (extracellular)?
Adaptive immunity 2 Types
Obligate intracelluar parasites
Attach to cell receptors
endocytosis into an endosome
Fusion of viral envelope with cell membrane (enveloped viruses only)
Translocation across cell membrane
Uncoating and replication within ho
Overall impact of microbes
everywhere in huge numbers
millions living on skin
trillions living in gut
~109 bacteria per gram gut contents
70% dry weight of faeces is composed of bacteria most of these
some are beneficial
Infection & Immunity
Types of microbial interactions
- can cause disease in individuals with normal host defences
- the normal microflora (or microbiota) found normally on those parts
of the body that are exposed to the external envir