ZOONOTIC DISEASES: cat, and it is passed from cat to cat via the feces each having their own species, without showing CAT-SCRATCH DISEASE AND of the cat flea (ctenocephalides felis). an active disease. Being able, as suggested in one report, to Causative agent TOXOPLASMOSIS pass the placental barrier in man, the impact Bartonella henselae is a curved, pleomorphic, (2 CE Hours) of bartonellosis is not well understood and rod-shaped gram-negative, facultative intracellular deserves further study. Many arthropods have Learning objectives: bacterium infecting the cat. It is of little ! been shown to carry Bartonella in addition to List the risk factors for Bartonella infections. consequence in the cat, with little symptomatology. ! cat fleas, including sand flies, human body lice, Explain how and where humans and animals Other species of Bartonella-infecting domestic cats rodent fleas, biting flies and ticks. Whether they can become infected. are Bartonella clarridgeiae, Bartonella koehlerae ! are actively involved in passing the organism to Explain how to diagnose, treat and prevent and Bartonella bovis. cat-scratch disease. mammalian hosts is not confirmed. ! In man, it produces a self-limiting disease varying List recommendations you can provide to pet Pathogenesis: While Bartonella henselae may be from painful regional lymphadenopathy after owners about treatment and prevention. the most common species in the cat, Bartonella ! being scratched or bitten by a cat to bacillary List the contraindications when prescribing clarridgeiae and Bartonella koehlerae are angiomatosis and peliosis hepatis, neuroretinitis, medications for cat-scratch disease. sometimes compromised as well and co-infections ! endocarditis, relapsing fever with bacteremia and List the risk factors for Toxoplasma gondii are possible. As many as six different strains of central nervous system complications. infections. Bartonella have co-habited in the same cat. ! Explain how and where humans and animals can become infected. Transmission Chronic recurrent bacteremia in the cat is ! Explain how to diagnose, treat and prevent Direct transmission from cat to cat is not known. frequent (25-41 percent) and often long toxoplasmosis. It requires an arthropod vector, with the carrier lasting, even years. Bacteremic phases will ! Describe the life cycle of these parasites. being the cat flea (Ctenocephalides felis), be interspersed with a-bacteremic ones, and ! List recommendations you can provide to pet although ticks have been considered possible the isolation of bacteria from the blood will owners about treatment and prevention. vectors as well. The cat flea sucks blood from the depend on the presence of bacteria at the time ! List the contraindications when prescribing infected cat and deposits the digested blood in of sample. Bacteremic cats do not necessarily medications for Toxoplasma gondii. its feces onto the fur coat of its host while taking show antibody, and antibody does not necessarily up its blood meal. Bacteremia for Bartonella interfere with bacteria in the blood stream, Introduction henselae is intermittent, and only blood from the possibly protected within erythrocytes and other Zoonoses are infectious diseases that are transmitted bacteremic phase will be infective. host cells. from animal to man. More than 60 percent of Flea feces appear as black specks, often comma Bartonella bacteria will attach to red blood cells emerging human pathogens are zoonotic. Causative shaped, on the cat fur. Eggs produced by the and endothelial cells of capillary walls, enter these groups of agents include parasites, fungi, bacteria flea are white. They may fall off the cat along cells and produce inflammatory tissue damage and viruses. Often of minor importance and with the flea feces, and the hatching larvae may throughout the body. In particular, they will affect producing only minor symptoms, they can lead to consume the feces and thus become infected. the mucosae of the respiratory system, including severe disease, especially in the very young and When the cat scratches the fleabite area, it picks the oral cavity, the eye, the skin and lymph nodes, those in weakened condition. up the infectious flea deposits in its claws and liver and spleen. The incidence of seropositivity in This course looks at two common diseases found nail beds. It can pass on the disease and continue cats is greater than the rates for bacteremia. mainly in cats that can be transmitted to man: its spread by scratching other cats. Even though Bartonella henselae does not appear cat-scratch disease, caused by the Bartonella The presence of Bartonella henselae DNA in to be of serious concern for human health, it is hensalae bacterium, and toxoplasmosis, caused the saliva of the cat has been confirmed by the one most widely known. by the Toxoplasma gondii parasite. While polymerase chain reaction and demonstrated the In the typical cat-scratch disease of man, the initial symptoms for both illnesses in many cases possible infectiousness of the cat bite. In fact, signs of the disease are single or multiple small are not serious, in others they can indeed be there have been suggestions that the organism bumps, developing to erythematous papules within dangerous or even fatal for humans. Veterinarians may cause plasma cell stomatitis, a progressive about 3-12 days after the infection near the cat need to understand both of these diseases and oral disease of the cat. The transmission of scratch or cat bite site, usually at hands, arms or help educate animal owners about them and the Bartonella henselae from cat to human happens face. These papules may progress, become pustules precautions they need to take. by cat scratch or bite, although there has been and ulcerate. The individual may show symptoms the occasional suggestion that the flea might Part I: Bartonellosis: Cat-scratch of fever, headache and anorexia. Within about three pass it on as well. There is one report suggesting weeks the regional, usually epitrochlear, cervical, disease transplacental transfer from mother to child. and axillary lymph nodes become inflamed, The diseases caused by the various members Bartonella quintana, causing trench fever, increase in size and become painful to the touch. In of the group Bartonella vary from insignificant is transmitted by body lice. While found in about one quarter of the cases, they may abscess and in man to deadly: Bartonella bacilliformis the unsanitary and crowded conditions of the burst. In the immunocompetent individual, healing (Carrion’s disease), Bartonella quintana (trench trenches of World War I, today it causes disease will take a few weeks, and within a few more weeks fever), Bartonella elizabethae (endocarditis), in the homeless, the drug addicted and those lead to full recovery. Bartonella grahamii (retinitis), Bartonella immunosuppressed by disease or chemotherapy. About one of 10 infected patients may exhibit vinsoni (endocarditis), Bartonella washonsis In the HIV/AIDS population in particular, one (myocarditis), Bartonella clarridgiae atypical symptoms, such as encephalitis, which frequently finds bacillary angiomatosis and occurs in 2-4 percent of all cases. Encephalitis is (bacteremia), Bartonella rochalimae (Carrion’s bacillary peliosis hepatis. diseaselike syndrome) and Bartonella henselae reflected by headache, confusion, altered mental (cat-scratch disease). There is some evidence of bartonellosis in dogs, status, restlessness, combativeness, disorientation, usually associated with granulomatous disease coma and evidence of meningitis and transient There are more than 20 known species of and endocarditis in larger-breed dogs. Bartonella nuchal rigidity. This encephalitis usually follows Bartonella. Bartonella henselae is distributed is also found in the blood of numerous animal the natural course of the disease, but it can also worldwide. The cat-scratch disease it produces is species, including gray squirrels, flying squirrels, occur without precursory evidence. Fortunately, the most widely recognized form of bartonellosis. groundhog, wood rat, cattle, deer, elk and sheep, it seems to be self-limiting, not requiring special The main host of this strain of Bartonella is the treatment and rarely leaving lasting impairment. Elite Page 1 Other atypical events, often following may be an enlarged spleen, typically an exaggerated fluid may show general elevated protein levels and lymhadenopathy and generalized influenza-like cutaneous and subcutaneous proliferation of blood mild pleocytosis. An EEG (electroencephalogram) symptoms, are: vessels and growthlike masses in visceral organs, will not bring much more. ■ Neuroretinitis, characterized by unilateral peliosis hepatis, fever, bacteremia, granulomatous There are no general laboratory tests with a vision loss, papilledema, swelling of the optic conjunctiva, optical neuritis, neuropathy, retinitis, quick answer. Minor rises in leukocyte count disk and macular exudates. keratitis, meningoencephalitis, osteomyelitis, and increased erythrocyte sedimentation rates ■ Parinaud’s oculoglandular syndrome arthritis, arthralgia, myositis, inflammatory bowel are unlikely to be useful. Histopathology in (granulomatous conjunctivitis and regional, disease, lymphadenopathy, pulmonary infiltrates the swollen lymph nodes includes lymphocytic same side lymphadenopathy) appearing in 6 and heart valve infection. infiltrates, granuloma and stellate abscess percent of patients. The cutaneous lesions may take the form of formation. Warthin-Starry