The presence of Rickettsia felis in Ctenocephalides felis fleas parasited in dogs in some provinces of Viet Nam

Abstract

Rickettsia is a gram-negative bacterium belonging to Alphaproteobacteria class. Among
Rickettsia species, Rickettsia felis is classified into the Spotted fever group (SFG). Until now
few studies have been conducted to identify the circulation of this bacterium in fleas parasited in
dogs. Morphological identification of 337 fleas collected from 32 dogs in 6 provinces and cities
of Viet Nam showed that flea species Ct. orientis predominated with a proportion of 66.4%,
followed by Ct. felis (30.6%) and Ct. canis (3.0%). In a total of 32 pooled Ct.felis samples
were tested by specific PCR method to identify Rickettsia SFG group, of which, there were 22
(68.8%) positive samples. The result of specific nested-PCR assay to identify R. felis indicated
that there were 53.1% of Ct. felis flea samples carried bacteria (R. felis). With the presence of
R. felis in fleas in dogs, the dog owners should be aware of self-protection from R. felis infection.