Rickettsiosi del cane: considerazioni sui risultati di sierodiagnosi condotte su cani sintomatici.

In Italy, during the last years, rickettsiae of the Spotted Fever Group (SFG), other than Rickettsia conorii, have been detected and some human clinical cases have been related to them. During a ten years period, from 2003 to 2012, sera of 3196 pet dogs were tested for antibodies to R. conorii and R. rickettsii antigens, employing the indirect immunofluorescent antibody test. All serodiagnosis had been requested by veterinarians for dogs with symptoms reportable to rickettsiosis (lymphoadenomegaly, anorexia, lethargy, fever). One hundred and sixty (5.0%) animals resulted positive to R. conorii, 603 (18.86%) to R. rickettsii, 36 (1.12%) reacted to both antigens; the total number of dogs positive to Rickettsia spp. was 763 (23.87%). Considering that R. rickettsii has never been isolated in Italy and the rest of Europe, the seropositive reactions are probably due to other SFG species which are here circulating. Further studies should be carried out to verify the pathogenicity of these agents for dogs.