The progression of an organism from an initial condition to a later condition, occurring within the cells or tissues of the host organism. This may (but not necessarily) include a filamentous growth form, and also can include secretion of proteases and lipases to break down host tissue. The host is defined as the larger of the organisms involved in a symbiotic interaction.
Comment:
This term partially replaces the obsolete term 'growth or development of symbiont in host ; GO:0044412'. See also 'biological process involved in interaction with host ; GO:0051701.
Synonyms:
narrow_synonym:
development of symbiont in host intercellular space; development of symbiont in host vascular tissue