Significant gaps in our knowledge exist due in part to the lack of reliable, standardized
or validated methods for testing effluents for aquatic animal pathogens. This is further
compounded by the lack of information on pathogen amplification when an aquatic animal
host, at various life stages and under different environmental conditions, becomes infected
or diseased. Additionally, many characteristics of aquatic animal pathogens are poorly
described yet are required in any risk assessment. These include information on the ability
of the pathogen to multiply and remain viable in water, the survival time outside the host,
and the number of infectious units required to cause infection and pathogenicity.