Page 1563 - Small Animal Internal Medicine, 6th Edition

CHAPTER 99 Zoonoses 1535

TABLE 99.1
VetBooks.ir Common Zoonotic Infections of Dogs and Cats—cont’d PRINCIPLE CLINICAL SYNDROMES

ROUTE OF EXPOSURE
AFFECTED
AGENT
Borrelia burgdorferi Spirochete Dogs Subclinical infection, fever, polyarthritis,
nephropathy
Humans Polyarthropathy, cardiac and CNS disease
Ehrlichia spp. Rickettsia Dogs Subclinical infection, fever, polysystemic
Humans Fever, polysystemic
Rickettsia rickettsii Rickettsia Dogs Subclinical infection, fever, polysystemic
Humans Fever, polysystemic

a Bartonella henselae, Bartonella koehlerae, and Bartonella clarridgeaie are transmitted among cats and dogs by C. felis and are therefore
listed under flea-borne disease. Other Bartonella spp. have zoonotic implications. Cats generally develop a higher level of bacteremia than
dogs and are therefore epidemiologically linked more frequently to human disease. The vector is unknown for some Bartonella spp.
b Dogs rarely shed enough organisms to be a public health risk.
c Larvation of eggs occurs after passage into the environment, so direct transmission is less likely than exposure through environmental
contamination.
d Most dogs and cats are infected by Cryptosporidium canis or C. felis, respectively, and these host-adapted species are rarely associated with
disease in humans.
e Infection of dogs in the United States is thought to be rare.
f Host-adapted and zoonotic assemblages exist. Dogs and cats can harbor zoonotic assemblages, but whether levels of infection result in
reinfection of humans is not established.
g Most Helicobacter spp. found in dogs and cats are host-adapted species. When Helicobacter pylori is detected in a dog or cat, it is likely
from reverse zoonotic transmission.
h Sporulation of oocysts occurs after passage into the environment, so direct transmission is less likely than exposure through environmental
contamination.
i Also can be vector-borne.
j Bartonella spp. DNA have been amplified from some ticks, but the extent of the role ticks play in the transmission of these agents has not
been fully ascertained.

BOX 99.1

General Guidelines for Veterinarians to Avoid Zoonotic Transfer of Disease
• Veterinarians and their staff should familiarize speak to the pet owner’s physician to clarify zoonotic
themselves with zoonotic issues and take an active role issues when indicated.
in discussing the health risks and benefits of pet • When public health–related advice is offered, it should
ownership with clients so that logical decisions be documented in the medical record.
concerning ownership and management of individual • When reportable zoonotic diseases are diagnosed,
animals can be made. appropriate public health officials should be contacted.
• The veterinary clinic should communicate that the staff • Diagnostic plans to assess for presence of organisms
understands conditions associated with immune with zoonotic potential should be offered, particularly
deficiency, is discreet, and is willing to help; signs or to owners with clinically ill pets.
posters can be effective for this purpose. • All dogs and cats should be vaccinated for rabies.
• Pet owners should be provided information concerning • Dogs and cats should be routinely administered drugs
veterinary or public health aspects of zoonoses, but that kill hookworms and roundworms.
veterinarians should not diagnose diseases in humans • Flea and tick control should be maintained at all times.
or discuss specific treatments. • Veterinary clinic staff members should teach owners
• Clinically ill pet owners should always be referred to a techniques to avoid being bitten or scratched.
physician for additional information and treatment. • Avoid needle sticks contaminated with blood or
• Veterinarians and physicians have different experiences effusions.
concerning zoonoses; veterinarians should volunteer to