Experimentally induced Bartonella henselae infections followed by challenge exposure and antimicrobial therapy in cats.
OBJECTIVE
To elucidate kinetics of Bartonella henselae bacteremia and IgG response, evaluate antibiotic therapy, and investigate challenge exposure in cats.


METHODS
Specific-pathogen-free cats.


METHODS
Cats were inoculated with B henselae or B quintana and monitored. Convalescent cats were challenge exposed with B henselae. Amoxicillin, enrofloxacin, erythromycin, and tetracycline HCl were evaluated for effect on B henselae bacteremia.


RESULTS
Cats developed B henselae bacteremia within 1 week; bacteremia persisted for longer than 2 months before subsiding spontaneously. IgG antibody titer developed shortly after onset of bacteremia; antibody co-existed with bacteremia for several weeks and remained detectable after bacteremia subsided. Cats inoculated with B quintana remained abacteremic. On challenge exposure to B henselae, cats previously infected with B henselae remained abacteremic; cats previously inoculated with B quintana supported B henselae infection. Tetracycline HCl and erythromycin depressed B henselae bacteremia; however, duration of bacteremia remained similar to that in untreated cats. Obvious signs of illness were not observed.


CONCLUSIONS
Long-duration, high-titer B henselae infections were highly reproducible in cats. Convalescent cats were immune to reinfection. B quintana-inoculated cats did not have evidence of infection and were susceptible to B henselae challenge exposure. Antibiotic therapy was incompletely efficacious in terminating cat bacteremia.


CONCLUSIONS
A cat with an inapparent B henselae infection must provisionally be regarded as a possible reservoir for infection for a minimum of 2 to 3 months. Convalescent cats are resistant to reinfection. Usual antibiotic therapy was not completely efficacious. Measurement of IgG antibody can be used to detect past or current infection.
Regnery
R L
RL
Viral and Rickettsial Zoonoses Branch, US Department of Health and Human Services, Atlanta, GA 30333, USA.
Rooney
J A
JA
Johnson
A M
AM
Nesby
S L
SL
Manzewitsch
P
P
Beaver
K
K
Olson
J G
JG
D000658:Amoxicillin / Q000627:therapeutic use; D016917:Angiomatosis, Bacillary / Q000188:drug therapy* / Q000503:physiopathology / Q000662:veterinary*; D000818:Animals; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D000890:Anti-Infective Agents; D000907:Antibodies, Bacterial / Q000097:blood; D016470:Bacteremia / Q000188:drug therapy / Q000503:physiopathology / Q000662:veterinary; D018416:Bartonella henselae / Q000302:isolation & purification; D002371:Cat Diseases; D002415:Cats; D000077422:Enrofloxacin; D004917:Erythromycin / Q000627:therapeutic use; D005260:Female; D024841:Fluoroquinolones; D007074:Immunoglobulin G / Q000097:blood; D015363:Quinolones / Q000627:therapeutic use; D013752:Tetracycline / Q000627:therapeutic use; D013997:Time Factors
D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents; D000907:Antibodies, Bacterial; D024841:Fluoroquinolones; D007074:Immunoglobulin G; D015363:Quinolones; D000077422:Enrofloxacin; D004917:Erythromycin; D000658:Amoxicillin; D013752:Tetracycline