Molecular examinations of Babesia microti in rodents and rodent-attached ticks from urban and sylvatic habitats in Germany

Abstract

Small mammals serve as reservoir hosts for tick-borne pathogens, especially for those which are not transmitted transovarially in ticks -such as Babesia microti. Molecular investigations on the prevalence of B. microti in wild small mammals and on attached ticks from differently structured areas may provide information on the circulation of B. microti in different ecological niches. In 2012 and 2013, 622 rodents (396 Myodes glareolus, 178 Apodemus flavicollis, 36 Apodemus sylvaticus, 4 Apodemus agrarius, 7 Microtus arvalis, 1 Microtus agrestis) were captured from three differently structured habitats (urban, sylvatic, recultivated) in Germany. Attached ticks were collected from 449 small mammals (3250 Ixodes ricinus, 7 Ixodes trianguliceps, 133 Dermacentor reticulatus). A representative selection of a maximum of 5 ticks per developmental stage and species per 30 rodents of each species, location and year resulting in 965 ticks was further investigated. DNA was extracted from tick, blood and spleen samples, and tested by PCR for the partial 18S rRNA gene of B. microti with subsequent sequencing. The prevalence was significantly higher in rodents from the sylvatic site (4.6%) than in rodents captured at both other sites (0-0.6%) (2= 11.95; p= 0.00125). Body and spleen weight of infected M. glareolus from the sylvatic site were significantly higher compared to those from non-infected individuals from that site (p = 0.00288 and p = 0.00017, respectively). Babesia microti DNA was detected in 3 out of 965 attached ticks (0.3%; 95%CI: 0-1) from all sites, but they derived exclusively from rodents captured at the sylvatic site. At the same site, I. ricinus nymphs (7.7%; 95%CI: 1-25.3) were significantly more often infected than I. ricinus larvae (0%; 95%CI: 0-1.3)(2 = 26.72; p <0.0001). The majority of positive rodents was also found at that site. I. trianguliceps occurred exclusively and the majority of M. glareolus at that site. Thus, it may be assumed that the circulation of B. microti is more efficient where this tick species and voles exist sympatrically than in areas with a predominant occurrence of Apodemus species. microti with subsequent sequencing. The prevalence was significantly higher in rodents from the sylvatic site (4.6%) than in rodents captured at both other sites (0-0.6%) (χ²= 11.95; p= 0.00125).Body and spleen weight of infected M. glareolus from the sylvatic site were significantly higher compared to those from non-infected individuals from that site (p=0.00288 and p=0.00017, respectively). Babesia microti DNA was detected in 3 out of 965 attached ticks (0.3%; 95%CI: 0-1) from all sites, but they derived exclusively from rodents captured at the sylvatic site. At the same site, I. ricinus nymphs (7.7%; 95%CI: 1-25.3) were significantly more often infected than I. ricinus larvae (0%; 95%CI: 0-1.3)(χ²=26.72; p <0.0001). The majority of positive rodents was also found at that site. I. trianguliceps occurred exclusively and the majority of M. glareolus at that site. Thus, it may be assumed that...

Rodents as Hosts of Pathogens and Related Zoonotic Disease Risk

“…To the best of our knowledge, our study is the first to provide evidence of piroplasmids circulating in A. niloticus. We can find some studies screening the presence of piroplasmids (belonging to the genera Babesia, Theileria, Cytauxzoon, and Rangelia) in different rodent species [11,69,70]. These tick-borne apicomplexan protozoans cause typical zoonotic diseases by parasitizing blood cells of numerous wild and domestic vertebrates worldwide, resulting in major economic and veterinary impacts [69].…”

“…Among the most important diseases 2 of 21 in terms of public health are salmonellosis, plague, leptospirosis, leishmaniasis, toxoplasmosis, rat-bit fever, taeniasis-like Capillaria hepatica, zoonotic babesiosis, Lassa fever, hemorrhagic fever with renal syndrome (HFRS), and the hantavirus cardiopulmonary syndrome (HCPS), both caused by Hantavirus. In addition, other Arenaviruses are responsible for South American Hemorrhagic Fevers (SAHF) [7][8][9][10][11][12]. More particularly, rodents may harbor different complex bacteria, such as Mycobacterium tuberculosis and Mycobacterium microti, Escherichia coli, agents of tularemia, tick-borne relapsing fever, bartonellosis, listeriosis, Lyme disease, Q fever, ehrlichiosis and others [13][14][15].…”

Isolation and characterization of Bordetella pseudohinzii in mice in China

“…The isolation of B. pseudohinzii in wild rodents together with our finding that the bacterica can shed through the feces and transmit to other animals raises public health concerns . Wild rodents represent an important reservoir of multiple human pathogens . Whether B. hinzii can transmit from wild rodents to infect humans requires further investigation in the future.…”

High prevalence of Babesia microti ‘Munich’ type in small mammals from an Ixodes persulcatus/Ixodes trianguliceps sympatric area in the Omsk region, Russia

“…Thus, B. microti 'Munich' type has been identified in small mammals in the studied areas of Eurasia inhabited with I. trianguliceps ticks. Notably, only B. microti 'US' type was found in small mammals in sampling areas in Germany and Slovenia, where the abundance of I. trianguliceps ticks was low or this tick species was absent (Duh et al 2003;Silaghi et al 2012;Obiegala et al 2015). Surprisingly, the predominant genetic group of B. microti has changed last years in (Siński et al 2006;Bajer et al 2014).…”