A. phagocytophilum: A nested PCR was carried out using the primers GE3a and GE10r for the primary reaction which amplifies a 932 bp fragment of the 16S rRNA gene of A. phagocytophilum, and the primers GE9f and GE2 for the secondary assay, which amplified a 546 bp fragment of the same gene [6].
Bartonella spp.: DNA samples were employed in a PCR assay to identify the Bartonella genus. The primers p24E and p12B, previously described by Relman et al. (1990) [7], were used in this protocol to amplify a 296 bp fragment of the Bartonella 16S rRNA gene.
B. burgdorferi s.l.: Primers JS1 and JS2 were used to amplify a 261 bp fragment of the 23S rRNA gene of B. burgdorferi s.l. [8].
C. burnetii: C. burnetii was identified by amplifying a 687 bp fragment of the IS1111a gene using primers Trans-1 and Trans-2 as described by Berri et al. (2009) [3].
Rickettsia spp.: PCR with the primers Rr190.70p and Rr190.701 were carried out to amplify a 632 bp fragment of the gene encoding the outer surface protein ompA of Rickettsia spp. as described by Roux et al. (1996) [9]. Since this protocol does not allow detecting Rickettsia helvetica, Rickettsia akari, Rickettsia australis, and Rickettsia bellii, a second PCR assay was performed using the primers RpCS.877p and RpCS.1258n which amplify a 381 bp fragment of the gltA gene [10].
All the amplification products were analyzed by electrophoresis on 1.5% agarose gel at 100 V for 45 min; gel was stained with ethidium bromide and observed. GelPilot 100 bp Plus Ladder (Qiagen) was used as DNA marker.