Evidence of the presence of spotted fever group rickettsiae in dogs and dog ticks of the central provinces in Spain

Abstract

To assess canine exposure to spotted fever group rickettsiae in the central provinces of Spain, ticks removed from dogs were studied by immunofluorescence (IF) staining. Twenty-eight out of 65 (43.0%) samples from ticks were positive. Sera from 58 dogs were also collected and the presence of antibodies to Rickettsia conorii studied. Thirty-four (58.6%) dogs presented significant titers by IF. Surveillance data from these provinces show the presence of Boutonneuse fever cases during recent years, evidence that dogs could serve as an indicator of rickettsial activity in these areas.

Isolation and Identification ofRickettsia massiliaefromRhipicephalus sanguineusTicks Collected in Arizona

“…In addition, R. rhipicephali, a close phylogenetic relative of R. massiliae (30,(53)(54)(55)(56)62) has also been detected in R. sanguineus ticks in Spain (33), Portugal (4), France (22), and the African continent (63). In these countries, particularly in Greece and Spain, it has been noted that a discrepancy exists between the sero- prevalence of antibodies to spotted fever group rickettsiae in local human populations, the incidence of reported rickettsioses (3,17,28,32,60), and the occurrence of severe and fatal forms of MSF (28,29,34,57,62). Similarly, there is a noticeable discrepancy in the prevalence of antibodies reactive with virulent R. conorii in dog populations and the occurrence of disease in different locations in Spain (32,34,60,61).…”

“…In these countries, particularly in Greece and Spain, it has been noted that a discrepancy exists between the sero- prevalence of antibodies to spotted fever group rickettsiae in local human populations, the incidence of reported rickettsioses (3,17,28,32,60), and the occurrence of severe and fatal forms of MSF (28,29,34,57,62). Similarly, there is a noticeable discrepancy in the prevalence of antibodies reactive with virulent R. conorii in dog populations and the occurrence of disease in different locations in Spain (32,34,60,61). These observations support the idea that both virulent and avirulent rickettsiae may be responsible for seroreactivity to spotted fever group agents in human and canine populations (9,10,17).…”

Phenotypic and genotypic characterization of spotted fever group Rickettsiae isolated from Catalan Rhipicephalus sanguineus ticks

“…Reports dealing with the resurgence of MSF in Spain in the early 1980s (31,33,45) have been behind the origin of several clinical studies of the disease and serosurveys in humans and dogs (16,20,22,25,31,(42)(43)(44)(45)(46). So far, the two strains isolated in Spain have been identified as R. conorii in Catalonia and R. rhipicephali in the region of Madrid (17,23,39).…”

“…In Spain, several cases of the disease have been described from all over the country, and serosurveys have been conducted in different areas (16,19,20,22,25,31,42,44,45). These studies indicated that epidemiological data recorded in the Catalan region differ from those recorded in other Spanish or Mediterranean regions.…”

Persistence of Antibodies to Rickettsia conorii in Dogs

“…5 In the central area of Spain, where many cases of MSF are currently diagnosed, this same parallelism between human cases and canine prevalence has also been observed. 8 Some authors have found seasonal differences in seroprevalence rates in dogs, suggesting the possibility that antibody titer may not persist in these animals. 9 Therefore, the purpose of this study was to assess the antibody titer to R. conorii in dogs, over a prolonged period of time.…”