I found a pretty cool article- based on post-mortem findings.
Here are the highlights:
MATERIALS AND METHODS
Between 1979 and 1983, 150 reptiles
were received at the Veterinary Services
Laboratory in Edmonton, Alberta.
Most came from private owners and
had been obtained through pet shop
retailers.
Ninety snakes representing
two families and seven genera, 46
lizards from six families and 12 genera,
and 14 turtles from one family and two
genera were submitted. Routine postmortem
examinations were performed
and selected tissues were fixed for histological
sections.
Organs with gross
pathological lesions or from cases suggestive
of septicemia were cultured. In
addition, in all cases a portion of the
distal third of the intestinal tract was
submitted for Salmonella isolation.
RESULTS
Thirty-one Salmonella serotypes
were identified from the respective
reptile families (Table I). Of particular
interest are the isolations of S. harmelem
from a boa of the genus Epicrates,
S. jangwani from an iguana and S.
mowanjum from a gecko. These
appear to be the first isolations of these
serotypes in Canada.
Forty-six (51%)
of the snakes were positive for Salmonellae
but only 15 (17%) died of salmonellosis
(i.e. 33% of Salmonella
positive animals). Similarly, 22 (48%)
of the lizards were positive while five
(11%) died of Salmonella infection
(i.e. 23% of positive animals). Somewhat
surprising was the low prevalence
of Salmonellae in turtles. Of the
14 examined, Salmonellae were
detected in only one asymptomatic
carrier.
Salmonellosis in snakes was commonly
manifested as severe, subacute
necrotizing enteritis involving most of
the intestines but more frequently the
posterior half (Fig. 1). From these
cases, Salmonellae were isolated in
pure culture and examinations for
entamoebae were negative. Septicemia
resulted in subacute hepatitis, sometimes
with granuloma formation.
Laboured breathing was the clinical
sign in a Boa constrictor with Salmonella
pneumonia characterized by
interstitial inflammatory cell infiltration
and much alveolar fibrin exudation.
These changes are similar to earlier
descriptions (11,12). Chronic
salmonellosis caused fibrosing interstitial
nephritis in an iguana. An
Ameiva lizard and an iguana suffered
from severe oophoritis. In two iguanas
the infection was associated with
myocarditis and in one of them also
with aortic valvular endocarditis (Fig.
2).
DISCUSSION
In attempting to assess the implications
to public health of the findings
reported herein, several points must be
borne in mind.
Although the high proportion
both of snakes and of lizards
infected with Salmonellae is disconcerting,
a serious hazard to humans
generally does not necessarily follow.
The serotypes encountered fall into
two main groups, those of sub-genus I
and the remainder belonging to subgenera
II or IV including mainly
strains previously classified as Arizona
hinshawii. Many, but not all subgenus
I types identified in this study
have commonly been found in poultry
or in animal feeds.
Chicks and other products of
domestic agriculture are major components
of diets fed to captive reptiles.
The high prevalence of Salmonellae in
such products is well recognized.
Without conclusive proof or firm circumstantial
evidence, these reptiles
cannot fairly be incriminated as an
important source of human salmonellosis.
Strains of sub-genera other than
sub-genus I rarely infect humans (16).
Recognizing that most captive snakes
and some lizards originate outside
Canada, infections with the very rare
serotypes reported are probably
acquired before importation into
Canada.
Persons handling reptiles, particularly
those maintaining them as pets,
should be aware of the attendant
hazards. However, given their restricted
popularity as pets and their dry
environment, there is no need at present
for public health surveillance of
these animals.
Our survey supports earlier findings
(13, 14) that only a small proportion of
Salmonella carrying reptiles show clinical
signs or die of salmonellosis.
