Page 70 - Veterinary Toxicology, Basic and Clinical Principles, 3rd Edition

VetBooks.ir Chapter 2

Epidemiology of Animal Poisonings

in the United States

Sharon M. Gwaltney-Brant

INTRODUCTION laboratories to report their findings for epidemiological
analysis. Most published information on animal poison-
Although animals are exposed to potentially toxic agents
ings has largely come from human or animal poison con-
on a daily basis, actual poisoning cases are uncommon
trol centers (APCC) that animal owners have contacted
when compared to other conditions of veterinary concern
regarding potential exposures to toxic agents (Haliburton
(infectious disease, trauma, metabolic disease, neoplasia,
and Buck, 1983; Hornfeldt and Borys, 1985; Hornfeldt
etc.). Clients will often present their animal with a suspi-
and Murphy, 1992, 1997, 1998; Forrester and Stanley,
cion of poisoning, only for the veterinarian to determine
2004) or from surveys of veterinary emergency centers or
that the animal is experiencing an unrelated ailment.
teaching hospitals (Osweiler, 1975; Cope et al., 2006).
When evaluating information regarding suspected poison-
Data from these sources can be helpful in determining
ing cases, it is important to consider the full exposure and
trends and identifying emerging toxicants, but because of
patient history before determining whether a particular
the frequent lack of complete historical information and
exposure is related to a clinical syndrome, as temporal
confirmatory testing, care must be taken in the interpreta-
coincidence does not necessarily equal causality.
tion of each case of suspected poisoning.
The fundamental rule of toxicology as stated by
Forrester and Stanley (2004) reported that exposures of
Paracelsus, considered to be the “father” of toxicology, is
animals to toxicants occurred more commonly in the sum-
“the dose makes the poison.” Obviously, the dose required
mer months, and this is consistent with data from the
to induce toxicosis will depend on a variety of factors,
American Society for the Prevention of Cruelty to
including the agent in question, species of animal exposed,
Animals (ASPCA) APCC AnTox database (Fig. 2.1),
and route of exposure. Based on information from poison
although a peak in December, associated with the holiday
control centers (PCC), the majority of animal exposures to
season, is also present in the APCC data (ASPCA Animal
potentially toxic agents result in no signs developing
Poison Control Center, unpublished data, 2010). The
(Hornfeldt and Murphy, 1992; Forrester and Stanley,
uptick in cases in the spring with peak cases during the
2004). However, clinically significant animal poisonings
summer is likely due to a variety of factors. Domestic ani-
do occasionally occur from exposures to natural or man-
mals tend to be more confined during the winter, particu-
made hazards. Knowledge of the most common features of
larly indoors, limiting their access to potentially toxic
animal poisonings can aid in instituting measures that may
agents. Toxic plants and animals are not frequently
help to minimize exposures of animals to toxicants.
encountered during the winter months in many areas, mak-
ing exposures to these potentially poisonous entities
unlikely. With the advent of warmer spring weather,
BACKGROUND
domesticated animals have more access to outdoors and
The lack of a central reporting agency for animal poison- the plants, insects and other animals that reside there. The
ings makes epidemiological study difficult. With no man- use of agents such as fertilizers, insecticides, and herbi-
dated reporting, many suspected poisoning cases are cides also increases during these months, thereby increas-
managed by the attending veterinarian and forgotten. ing the risk of animal exposures to these agents. Cool, wet
Confirmatory testing at veterinary diagnostic laboratories spring weather favors the rapid appearance of potentially
is not common, and no central mechanism exists for these toxic mushrooms, while hot summer weather can trigger
Veterinary Toxicology. DOI: http://dx.doi.org/10.1016/B978-0-12-811410-0.00002-7
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