Rickettsia felis in fleas from Catalonia (Northeast Spain).
BACKGROUND
Rickettsia felis produces a syndrome indistinguishable from murine typhus, which has been described in Spain. R. felis is transmitted to humans by fleas. Although no clinical case has been described so far, serologic evidence of infections in humans, cats, and dogs has been obtained in our area. However, no study has been conducted regarding its presence in vectors. Recognition of routes of transmission is of great importance to prevent infection in humans. Taking into account these results, R. felis seems to be present in animals that are in contact with humans. The aim of this study was to determine the presence of R. felis in the fleas of cats and dogs from Northeast Spain, to show the presence of peridomestic cycle in our area.


METHODS
Between May 2006 and July 2008, 78 fleas were collected. Sixty-three fleas were recovered from kennels. Most of them were collected from cages and a few of them on dogs and cats living in kennels. Fifteen fleas were collected from dogs and cats attended at a veterinary clinic. Fleas were rinsed with ethanol, dried, identified, and stored at 4°C. DNA was extracted from each flea individually. Rickettsial DNA was determined by quantitative real-time polymerase chain reaction. OmpB-specific primers and molecular beacon probes targeting specifically R. felis were used.


RESULTS
All 78 fleas were identified as Ctenocephalides felis. R. felis was detected in 34 (43.6%) fleas. No nucleic acids were amplified from negative controls and expected results were obtained from positive controls. Eight positive samples were also confirmed by sequencing.


CONCLUSIONS
R. felis was found in a high percentage of Ct. felis from cats and dogs. It seems that there is a peridomestic cycle in Northeast Spain, which would allow contact of R. felis with humans.
Nogueras
María-Mercedes
MM
Department of Infectious Diseases, Corporació Sanitària Parc Taulí, Fundació Parc Taulí-Institut Universitari, Universitat Autònoma de Barcelona, Sabadell, Spain. mnogueras@tauli.cat
Pons
Immaculada
I
Ortuño
Anna
A
Lario
Sergio
S
Segura
Ferran
F
D000822:Animal Husbandry; D000818:Animals; D002371:Cat Diseases / Q000382:microbiology / Q000469:parasitology* / Q000635:transmission; D002415:Cats; D017931:DNA Primers; D030561:Databases, Nucleic Acid; D004283:Dog Diseases / Q000382:microbiology / Q000469:parasitology* / Q000635:transmission; D004285:Dogs; D058267:Flea Infestations / Q000469:parasitology / Q000635:transmission / Q000662:veterinary*; D006801:Humans; D007303:Insect Vectors / Q000382:microbiology*; D016133:Polymerase Chain Reaction; D012282:Rickettsia Infections / Q000635:transmission; D041161:Rickettsia felis / Q000235:genetics / Q000302:isolation & purification*; D005423:Siphonaptera / Q000382:microbiology*; D013030:Spain
D017931:DNA Primers