and true epidemiological connections of an infectious association.
Many bacteria generally considered as fish zoonoses are facultative
pathogens with an environmental niche and often it is not
possible to differentiate between infections-in-common and strict
zoonoses. The present review will detail what is known about the
nature of infections with various bacterial agents in humans and
fishes, as well as their transmission routes.
When drawing linkages between human and fish infections it is
important to determine whether they are caused by the same organism.
Most of the existing literature is limited to phenotypic/
biochemical descriptions of isolates from fishes and humans, and there
is a paucity of information as to whether infections in fishes and
humans are caused by the same strains, serotypes, or in some cases,
species of bacteria. Use of molecular techniques has improved our
ability to determine whether human infections have arisen directly
from infected fishes, environmental sources, or through exposure to
transiently colonized or contaminated fish products (Table 1). Most
bacteria identified as piscine zoonoses by previous authors will be
covered in this review, with the addition of Lactococcus garvieae, which
has not been discussed in previous reviews.