Genetic characterization of Candidatus Rickettsia vini, a new rickettsia amplified in ticks from La Rioja, Spain.

A total of 222 ticks removed from birds in La Rioja (Spain) were screened for spotted fever group rickettsia species using ompA PCR assays. Rickettsia monacensis (n=1) and R. sibirica (n=1) were detected. Apart from that, 27 out of 29 Ixodes spp. DNA extracts that tested positive for ompA did not match with any validated spotted fever group rickettsia. Multilocus sequence typing for 16S rRNA, gltA, ompB, sca4, and 17-kDa antigen genes was performed, and R. heilongjiangensis was found to be the nearest validly published spotted fever group rickettsia. Based on genetic criteria agreed by experts, this genotype can be classified as a new Candidatus Rickettsia sp. and was named Candidatus Rickettsia vini.