Abstract
Twelve rickettsial isolates, from Rhipicephalus sanguineus, R. turanicus, Dermacentor marginatus and Hyalomma marginatus, were subjected to genotypic analysis. Amplification of specific DNA sequences, restriction endonuclease digestion of amplified DNA products, and gel electrophoresis were used to identify specific DNA fragment-banding patterns. Five patterns were resolved. Four were homologous with those of previously described rickettsial genotypes, R. conorii, R. slovaca, R. rhipicephali and R. massiliae. The fifth pattern differed by only a single altered restriction endonuclease cleavage site. For the first time in Portugal a widely distributed spectrum of spotted fever group rickettsia was found among potential vector species stressing the need to determine their potential for human and domestic animals infection.