14.3: Penetrating Host Defenses Last updated Jan 3, 2021 Save as PDF 14.2C: Cooperation Among Microorganisms 14.3A: Penetrating Host Defenses Page ID8716 BoundlessBoundless ( \newcommand{\kernel}{\mathrm{null}\,}\) Topic hierarchy14.3A: Penetrating Host DefensesAlthough humans host many beneficial bacteria, certain pathogens can penetrate host defenses and cause illness or disease.14.3B: Pili and Pilus AssemblyAttachment of bacteria to host surfaces often aided by pili or fimbrae is required for colonization during infection or to initiate formation of a biofilm.14.3C: Biofilms and Infections