Cats Surviving Natural Infection with Cytauxzoon felis: 18 Cases (1997–1998)

Abstract

Eighteen cats surviving natural infection with Cytauxzoon felis were identified. All cats came from a limited geographic area in northwestern Arkansas and northeastern Oklahoma. Clinical signs in most cats were similar to those described for cytauxzoonosis; however, 4 cats were asymptomatic. All cases were initially diagnosed by microscopic identification of signet ring-shaped piroplasms in erythrocytes of peripheral blood smears. Four of 4 cats tested had detectable serum antibodies to C felis. Four different cats were positive by polymerase chain reaction (PCR). Partial sequencing of the PCR product from 1 cat revealed >99% homology with the reported sequence of C felis. Repeated examination of blood smears from 12 cats revealed that the erythroparasitemia was generally persistent for the duration of follow-up (3-154 days). Survival did not seem dependent on treatment, as only 1 cat was treated with a drug with potential antiprotozoal activity (imidocarb dipropionate), and 4 cats received no treatment. The findings of this study may indicate the existence of a less virulent strain of C felis.

The Biological Survey of Canada: A Personal History

“…Feline cytauxzoonosis is an invariably fatal blood protozoan disease caused by Cytauxzoon felis Kier (Achromatorida: Theileriidae) (Meinkoth et al 2000;Meinkoth and Kocan 2005). It is found in the south central and southeastern United States of America, notably Texas, Oklahoma, Missouri, Arkansas, Louisiana, Georgia, Mississippi, and Florida.…”

“…Although generally a fatal disease, there have been reports of cats surviving the disease (Meinkoth et al 2000). Some of these cats showed a persistent erythro-parasitaemia.…”

Fatal Cytauxzoonosis in a Free-ranging Bobcat (Lynx rufus)

“…Survival of infected domestic cats is unusual. A recent report described 18 domestic cats that survived natural infection by C. felis (Meinkoth et al, 2000). Prior to that only two naturally infected domestic cats were known to have survived (Walker and Cowell, 1995;Kier and Greene, 1998).…”

Infección natural por Cytauxzoon felis en onza parda (Puma concolor) de vida libre proveniente de la región suroeste de Mato Grosso do Sul, Brasil

“…No presente relato, nenhuma manifestação clínica compatível com a cytauxzoonose foi observada, corroborando com os achados de Soares et al (2004) que detectaram o agente em uma onça parda, e André et al (2009) que identificaram material genético do protozoário em seis jaguatiricas (Leopardus pardalis), duas onças pardas e uma onça pintada (Panthera onca). Em contrapartida, doença fatal em leões (Panthera leo), tigre de bengala e tigre branco (Panthera tigres) foi descrita (Garner et al, 1996, Jakob & Wesemeier, 1996, Peixoto et al, 2007 A presença desse patógeno, na ausência de sinais clínicos, pode estar associada à eficácia do sistema imune, no entanto, a hipótese de uma estirpe menos patogênica envolvida na infecção ou, a possibilidade de que o Puma concolor atue, assim como o Lynx rufus, como hospedeiro reservatório natural da doença deve ser investigada (Meinkoth et al, 2000, Soares et al, 2004.…”