Use of a polymerase chain reaction assay to detect and differentiate two strains of Haemobartonella felis in naturally infected cats.
OBJECTIVE
To develop a polymerase chain reaction (PCR) assay that detects and differentiates the Ohio strain of Haemobartonella felis (H. felis-OH) and the California strain of H. felis (H. felis-CA) and to apply the assay to blood samples from cats with and without suspected haemobartonellosis (suspect and control cats, respectively).


METHODS
220 blood samples were examined; 82 were from suspect cats, and 138 were from control cats.


METHODS
A PCR assay was designed to detect and differentiate H. felis-OH and H. felis-CA.


RESULTS
On the basis of PCR assay results, the overall prevalence of H. felis infection was 19.5% (43/220). Suspect cats (28.0%; 23/82) were significantly more likely than control cats (14.5%; 20/138) to be H. felis infected. Significantly greater numbers of suspect cats were H. felis-OH infected (12.2%, 9/82) or H. felis-OH and H. felis-CA infected (4.9%, 4/82) than control cats (0% [0/138] and 0.7% [1/138], respectively). Significantly more anemic cats were H. felis-OH infected (14.3%; 4/28) or H. felis-OH and H. felis-CA infected (7.1%; 2/28) than nonanemic cats (2.3% [3/128] and 0.8% [1/128], respectively). The PCR assay was more accurate than cytologic examination for detection of H. felis.


CONCLUSIONS
Haemobartonella felis infections are more common in cats than previously recognized. Haemobartonella felis-OH is apparently more pathogenic than H. felis-CA. The PCR assay is more accurate than cytologic examination for detection of H. felis infection and is an effective clinical tool for the detection and differentiation of both H. felis strains known to infect cats.
Jensen
W A
WA
Heska Corporation, Fort Collins, CO, USA.
Lappin
M R
MR
Kamkar
S
S
Reagan
W J
WJ
D000710:Anaplasmataceae / Q000737:chemistry / Q000145:classification* / Q000235:genetics; D000711:Anaplasmataceae Infections / Q000097:blood / Q000382:microbiology / Q000662:veterinary*; D000818:Animals; D001483:Base Sequence; D001772:Blood Cell Count / Q000662:veterinary; D002371:Cat Diseases / Q000097:blood / Q000175:diagnosis / Q000382:microbiology*; D002415:Cats; D004269:DNA, Bacterial / Q000235:genetics; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction / Q000379:methods / Q000662:veterinary*; D016415:Sequence Alignment; D012689:Sequence Homology, Nucleic Acid
D004269:DNA, Bacterial