Learning Objectives

• Explain how different parts of the immune system co-operate to protect the host from infectious diseases
• Explain some of the ways that bacteria use to evade and subvert immunity, including: types of virulence factors, how bacteria damage hosts, and different cellular niches of bacteria
• Describe how protective immunity varies depending on the location of bacteria

Pathogens

• what does normal flora refer to?
• what is a pathogen?
• what are the 4 classes of pathogens?
• what does pathogenicity mean?
• what does virulence mean?
• what are opportunistic pathogens?
• the chance that an organism causes infection depends on [3 factors]?

Virulence Factors

• what virulence factors can bacteria have?
• how can pathogens escape epithelial defences?
• how can pathogens escape phagocytosis and innate immunity?
• how can pathogens evade adaptive immunity?

Host-Pathogen Interactions

• why do humans and pathogens have a bidirectional relationship?