Serological evidence of exposure to zoonotic tick-borne bacteria in pheasants (Phasianus colchicus)

Abstract

Introduction and objective. Previous studies on tick-borne pathogens in the avian population have focused mainly on the detection of the agents in ticks collected from birds, but data about the presence of tick-borne bacteria in these animals are scant. The aim of the presented study was to verify the exposure to some zoonotic tick-borne bacteria, in particular, Anaplasma phagocytophilum, Borrelia burgdorferi sensu lato, Coxiella burnetii, and the Rickettsia species of the Spotted Fever Group (SFG), in pheasants (Phasianus colchicus) living in a central Italy area, characterized by conditions favourable for the diffusion of the ticks. Materials and method. Blood serum samples from 276 farm-reared pheasants were examined by indirect immunofluorescence antibody test to detect antibodies against the 4 reported pathogens. Results. A total of 124 (44.92%) birds resulted as seropositive: in particular 3 (1.08%) to C. burnetii, 31 (11.23%) to A. phagocytophilum, 46 (16.67%) to B. burgdorferi s.l., 49 (17.75%) to SFG Rickettsia spp. antigens. Three pheasants resulted positive both to A. phagocytophilum and B. burgdorferi s.l. antigens, whereas 2 -both to B. burgdorferi s.l. and SFG Rickettsia spp. antigens. The antibody titers varied from 1:40-1:320. Conclusions. The obtained results show that the pheasants had developed antibodies to the investigated tick-borne agents. For this reason, they seem to be involved in the epidemiology of the studied tick-borne bacteria.

Potential Role of Avian Populations in the Epidemiology of Rickettsia spp. and Babesia spp.

“…The detected prevalence could include antibodies against R. conorii, as well as other SFG rickettsiae due to the common antigens [7]. In fact, several SFG rickettsiae, mainly R. conorii, R. helvetica, R. massiliae, R. slovaca, R. aeschlimannii, R. africae, R. monacensis, R. roultii were circulating in Italy at the sampling time, as observed in molecular investigations in animals and ticks [17].…”

“…A serological survey was carried out in pheasants (P. colchicus) to verify the occurrence of antibodies against some tick-borne pathogens. All the tested pheasants lived in an area of central Italy with conditions favorable for ticks' diffusion, such as a rich vegetation and various large and small mammals [17]. The 17.75% of the examined animals were positive to R. conorii antigen [17].…”

“…All the tested pheasants lived in an area of central Italy with conditions favorable for ticks' diffusion, such as a rich vegetation and various large and small mammals [17]. The 17.75% of the examined animals were positive to R. conorii antigen [17]. The detected prevalence could include antibodies against R. conorii, as well as other SFG rickettsiae due to the common antigens [7].…”

Prevalence of Lyme Disease and Relapsing Fever Borrelia spp. in Vectors, Animals, and Humans within a One Health Approach in Mediterranean Countries

“…Besides the animals mentioned above, wild brown hares captured in central Italy were found to carry anti- Borreliella antibodies [ 258 ], and one blood sample from a wild boar was positive for Borreliella DNA [ 259 ]. Additionally, farm-reared pheasants were seropositive [ 260 ] and feral pigeons were positive for the presence of Borreliella DNA [ 261 ]. Finally, it was demonstrated that Borreliella DNA was found in blood samples collected from the heart of hunted red deer [ 262 ], as well as antibodies against Borreliella in blood samples from fallow deer from farms [ 263 ].…”