The potential role of migratory birds in transmission cycles of Babesia spp., Anaplasma phagocytophilum, and Rickettsia spp

Ixodes ricinus and Its Transmitted Pathogens in Urban and Peri-Urban Areas in Europe: New Hazards and Relevance for Public Health

Tick-borne diseases represent major public and animal health issues worldwide. Ixodes ricinus, primarily associated with deciduous and mixed forests, is the principal vector of causative agents of viral, bacterial, and protozoan zoonotic diseases in Europe. Recently, abundant tick populations have been observed in European urban green areas, which are of public health relevance due to the exposure of humans and domesticated animals to potentially infected ticks. In urban habitats, small and medium-sized mammals, birds, companion animals (dogs and cats), and larger mammals (roe deer and wild boar) play a role in maintenance of tick populations and as reservoirs of tick-borne pathogens. Presence of ticks infected with tick-borne encephalitis virus and high prevalence of ticks infected with Borrelia burgdorferi s.l., causing Lyme borreliosis, have been reported from urbanized areas in Europe. Emerging pathogens, including bacteria of the order Rickettsiales (Anaplasma phagocytophilum, "Candidatus Neoehrlichia mikurensis," Rickettsia helvetica, and R. monacensis), Borrelia miyamotoi, and protozoans (Babesia divergens, B. venatorum, and B. microti) have also been detected in urban tick populations. Understanding the ecology of ticks and their associations with hosts in a European urbanized environment is crucial to quantify parameters necessary for risk pre-assessment and identification of public health strategies for control and prevention of tick-borne diseases.

Piroplasms of New Zealand seabirds

Blood and ectoparasitic ticks were collected from migratory seabirds in New Zealand, including Australasian gannets (n = 13) from two sites and red-billed gulls (n = 9) and white-fronted terns (n = 2) from a third location. Blood smears were screened for parasite presence by microscopy, while DNA from blood samples was subjected to PCR for the presence of tick-transmitted protozoan haemoparasites belonging to the order Piroplasmida. Parasites were identified by comparing small subunit ribosomal RNA (18S rDNA) gene sequences to related sequences on GenBank. Analyses indicated that nine birds were infected with unknown variants of a Babesia poelea-like parasite (recorded as genotypes I and II), while four harboured a piroplasm that was genetically similar to Babesia kiwiensis. There was no parasite stratification by bird species; both the gannets and gulls were positive for all three parasites, while the terns were positive for the B. kiwiensis-like and the B. poelea-like (genotype I) parasites. The B. kiwiensis-like parasite found in the birds was also found in two species of ticks: Carios capensis and Ixodes eudyptidis. This represents the first report of Babesia-positive ticks parasitising seabirds in New Zealand. The lack of host specificity and evidence of wide ranging distributions of the three piroplasm genotypes suggests there is a high degree of haemoparasite transmission occurring naturally between New Zealand seabird populations and species.

Tick-borne pathogens in ticks collected from breeding and migratory birds in Switzerland

From 2007 to 2010, 4558 migrating and breeding birds of 71 species were caught and examined for ticks in Switzerland. A total of 1205 specimens were collected; all were Ixodes ricinus ticks except one Ixodes frontalis female, which was found on a common chaffinch (Fringilla coelebs) for the first time in Switzerland. Each tick was analysed individually for the presence of Borrelia spp., Rickettsia spp., Anaplasma phagocytophilum and tick-borne encephalitis virus (TBEV). Altogether, 11.4% of birds (22 species) were infested by ticks and 39.8% of them (15 species) were carrying infected ticks. Bird species belonging to the genus Turdus were the most frequently infested with ticks and they were also carrying the most frequently infected ticks. Each tick-borne pathogen for which we tested was identified within the sample of bird-feeding ticks: Borrelia spp. (19.5%) and Rickettsia helvetica (10.5%) were predominantly detected whereas A. phagocytophilum (2%), Rickettsia monacensis (0.4%) and TBEV (0.2%) were only sporadically detected. Among Borrelia infections, B. garinii and B. valaisiana were largely predominant followed by B. afzelii, B. bavariensis, B. miyamotoi and B. burgdorferi ss. Interestingly, Candidatus Neoehrlichia mikurensis was identified in a few ticks (3.3%), mainly from chaffinches. Our study emphasizes the role of birds in the natural cycle of tick-borne pathogens that are of human medical and veterinary relevance in Europe. According to infection detected in larvae feeding on birds we implicate the common blackbird (Turdus merula) and the tree pipit (Anthus trivialis) as reservoir hosts for Borrelia spp., Rickettsia spp. and A. phagocytophilum.

Surveillance for Ixodes pacificus and the tick-borne pathogens Anaplasma phagocytophilum and Borrelia burgdorferi in birds from California's Inner Coast Range

We investigated the involvement of birds in the ecology of the western black-legged tick, Ixodes pacificus, and its associated zoonotic bacteria, Borrelia burgdorferi and Anaplasma phagocytophilum, at two interior coast-range study sites in northern California. Anaplasma phagocytophilum, the agent of granulocytic anaplasmosis (GA), and B. burgdorferi s.s., the agent of Lyme disease (LD), are tick-borne pathogens that are well established in California. We screened blood and ticks from 349 individual birds in 48 species collected in 2011 and 2012 using pathogen-specific PCR. A total of 617 immature I. pacificus was collected with almost three times as many larvae than nymphs. There were 7.5 times more I. pacificus at the Napa County site compared to the Yolo County site. Two of 74 (3%) nymphal pools from an Oregon junco (Junco hyemalis) and a hermit thrush (Catharus guttatus) and 4 individual larvae (all from Oregon juncos) were PCR-positive for B. burgdorferi. Blood samples from a golden-crowned sparrow (Zonotrichia atricapilla) and a European starling (Sturnus vulgaris) were positive for A. phagocytophilum DNA at very low levels. Birds that forage on ground or bark and nest on the ground, as well as some migratory species, are at an increased risk for acquiring I. pacificus. Our findings show that birds contribute to the ecologies of LD and GA in California by serving as a blood-meal source, feeding and transporting immature I. pacificus, and sometimes as a source of Borrelia infection.

Rickettsiaceae and Anaplasmataceae infections in Ixodes ricinus ticks from urban and natural forested areas of Poland

Background

Ixodes ricinus is a major vector for a range of microbial pathogens and the most prevalent and widely distributed tick species on the European continent, occurring in both natural and urban habitats. Nevertheless, little is known about the relative density of ticks in these two ecologically distinct habitats and the diversity of tick-borne pathogens that they carry.

Methods

We compared densities of questing I. ricinus nymphs and adults in urban and natural habitats in Central and Northeastern Poland, assessed the prevalence and rate of co-infection with A. phagocytophilum, Rickettsia, Ehrlichia and ‘Ca. Neoehrlichia spp.’ in ticks, and compared the diversity of tick-borne pathogens using molecular assays (PCR).

Results

Of the 1325 adults and nymphs, 6.2% were infected with at least one pathogen, with 4.4%, 1.7% and less than 0.5% being positive for the DNA of Rickettsia spp., A. phagocytophilum, Ehrlichia spp. and Ca. N. mikurensis, respectively. Although tick abundance was higher in natural habitats, the prevalence of the majority of pathogens was higher in urban forested areas.

Conclusion

We conclude that: (i) zoonotic genetic variants of A. phagocytophilum are widely distributed in the Polish tick population, (ii) although the diversity of tick borne pathogens was higher in natural habitats, zoonotic species/strains were detected only in urban forests, (iii) and we provide the first description of Ca. N. mikurensis infections in ticks in Poland.

Importation of exotic ticks and tick-borne spotted fever group rickettsiae into the United States by migrating songbirds

Birds are capable of carrying ticks and, consequently, tick-transmitted microorganisms over long distances and across geographical barriers such as oceans and deserts. Ticks are hosts for several species of spotted fever group rickettsiae (SFGR), which can be transmitted to vertebrates during blood meals. In this study, the prevalence of this group of rickettsiae was examined in ticks infesting migratory songbirds by using polymerase chain reaction (PCR). During the 2009 and 2010 spring migration season, 2064 northward-migrating passerine songbirds were examined for ticks at Johnson Bayou, Louisiana. A total of 91 ticks was removed from 35 individual songbirds for tick species identification and spotted fever group rickettsia detection. Ticks were identified as Haemaphysalis juxtakochi (n=38, 42%), Amblyomma longirostre (n=22, 24%), Amblyomma nodosum (n=17, 19%), Amblyomma calcaratum (n=11, 12%), Amblyomma maculatum (n=2, 2%), and Haemaphysalis leporispalustris (n=1, 1%) by comparing their 12S rDNA gene sequence to homologous sequences in GenBank. Most of the identified ticks were exotic species originating outside of the United States. The phylogenetic analysis of the 71 ompA gene sequences of the rickettsial strains detected in the ticks revealed the occurrence of 6 distinct rickettsial genotypes. Two genotypes (corresponding to a total of 28 samples) were included in the Candidatus Rickettsia amblyommii clade (less than 1% divergence), 2 of them (corresponding to a total of 14 samples) clustered with Rickettsia sp. "Argentina" with less than 0.2% sequence divergence, and 2 of them (corresponding to a total of 27 samples), although closely related to the R. parkeri-R. africae lineage (2.50-3.41% divergence), exhibited sufficient genetic divergence from its members to possibly constitute a new rickettsial genotype. Overall, there does not seem to be a specific relationship between exotic tick species, the rickettsiae they harbor, or the reservoir competence of the corresponding bird species.

Detection of microbial agents in ticks collected from migratory birds in central Italy

Tick species characterization and molecular studies were performed within ornithological surveys conducted during 2010 and 2011 in the Lazio Region of central Italy. A total of 137 ticks were collected from 41 migratory birds belonging to 17 species (four partial migrants and 13 long-distance migrants). Most ticks were nymphs, with a predominance of Hyalomma marginatum marginatum and H. m. rufipes, and a small portion of Ixodes and Amblyomma species. All tick species analyzed were infected, and the molecular pathogen recognition revealed the presence of Rickettsia aeschlimannii, Rickettsia africae, Erlichia spp., Coxiella burnetii, Borrelia burgdorferi sensu lato group, and Babesia microti, whereas no genomic DNA of Bartonella spp. or Francisella tularensis was detected. The results of the survey show that H. marginatum ticks appear to be a vector of microbial agents that may affect human and animal health and that migratory birds may be an important carrier of these ticks. Additional studies are needed to better investigate the role of migratory birds in the epidemiology of these pathogens.

Do the ticks of birds at an important migratory hotspot reflect the seasonal dynamics of Ixodes ricinus at the migration initiation site? A case study in the Danube Delta

Migratory birds play important roles as distributors of ticks within and between continents. In the Old World, the most important migratory route of birds links Asia, Europe and Africa. During their migration, birds use various stopover sites, where they feed and rest and where ticks may attach or detach, creating new natural foci for vector-borne diseases. Danube Delta is one of the most important migration hotspots and so far no studies were focused on ticks of migratory birds herein. The aim of the present study was to assess the species diversity and seasonal dynamics of ticks parasitizing migratory birds in Danube Delta Biosphere Reserve. Migratory birds were trapped on Grindul Lupilor (44°41′N; 28°56′E) using mist nets during 4 migratory seasons (2 spring and 2 autumn) in 2011 and 2012. From each bird, all the ticks were collected and identified based on morphological features. Epidemiological parameters (prevalence, mean abundance, mean intensity) were calculated and all data were analysed statistically based on the season (spring and autumn), regional status of birds (migrants and breeding) and foraging behaviour (ground feeders, reed-bed feeders, foliage feeders). A total of 1434 birds (46 species) were captured. Ticks were found on 94 birds (10 species). Significantly more migratory birds hosted ticks, compared to resident birds. The 400 collected ticks belonged to four species: Ixodes ricinus (92.25%), I. arboricola (6.25%), I. redikorzevi (1.00%) and Haemaphysalis punctata (0.50%). A higher prevalence was found for I. ricinus in spring, with higher prevalence of nymphs in this season, while larvae occurred with the same prevalence in both seasons. Larval intensity was higher during spring and nymphs were more abundant during autumn. The seasonal differences in our study may be related not to the local seasonal dynamics of ticks, but on the seasonal dynamics at the site of migration initiation.

Ixodes ricinus and Its Transmitted Pathogens in Urban and Peri-Urban Areas in Europe: New Hazards and Relevance for Public Health

Tick-borne diseases represent major public and animal health issues worldwide. Ixodes ricinus, primarily associated with deciduous and mixed forests, is the principal vector of causative agents of viral, bacterial, and protozoan zoonotic diseases in Europe. Recently, abundant tick populations have been observed in European urban green areas, which are of public health relevance due to the exposure of humans and domesticated animals to potentially infected ticks. In urban habitats, small and medium-sized mammals, birds, companion animals (dogs and cats), and larger mammals (roe deer and wild boar) play a role in maintenance of tick populations and as reservoirs of tick-borne pathogens. Presence of ticks infected with tick-borne encephalitis virus and high prevalence of ticks infected with Borrelia burgdorferi s.l., causing Lyme borreliosis, have been reported from urbanized areas in Europe. Emerging pathogens, including bacteria of the order Rickettsiales (Anaplasma phagocytophilum, "Candidatus Neoehrlichia mikurensis," Rickettsia helvetica, and R. monacensis), Borrelia miyamotoi, and protozoans (Babesia divergens, B. venatorum, and B. microti) have also been detected in urban tick populations. Understanding the ecology of ticks and their associations with hosts in a European urbanized environment is crucial to quantify parameters necessary for risk pre-assessment and identification of public health strategies for control and prevention of tick-borne diseases.

Prevalence of tick-borne pathogens in ticks collected from migratory birds in Latvia

Migratory birds act as hosts and long-distance vectors for several tick-borne infectious agents. Here, feeding Ixodes ticks were collected from migratory birds during the autumn migration period in Latvia and screened for the presence of epidemiologically important non-viral pathogens. A total of 93 DNA samples of ticks (37 larvae and 56 nymphs) removed from 41 birds (order Passeriformes, 9 species) was tested for Lyme borreliosis spirochaetes, Anaplasma phagocytophilum, Rickettsia spp., and Babesia spp. Borrelia burgdorferi DNA was detected in 18% of the tick samples, and a majority of infected ticks were from thrush (Turdus spp.) birds. Among the infected ticks, Borrelia valaisiana was detected in 41% of cases, Borrelia garinii in 35%, and mixed Bo. valaisiana and Bo. garinii infection in 24%. Anaplasma phagocytophilum DNA was detected in 2% of ticks, R. helvetica in 12%, and Babesia spp. pathogens in 4% of ticks. Among these samples, 3 Babesia species were identified: Ba. divergens, Ba. microti, and Ba. venatorum. Coinfection with different pathogens that included mixed infections with different Borrelia genospecies was found in 20% of nymphal and 3% of larval Ixodes ticks. These results suggest that migratory birds may support the circulation and spread of medically significant zoonoses in Europe.

Human babesiosis in Europe: what clinicians need to know

Although best known as an animal disease, human babesiosis is attracting increasing attention as a worldwide emerging zoonosis. Humans are commonly infected by the bite of ixodid ticks. Rare ways of transmission are transplacental, perinatal and transfusion-associated. Infection of the human host can cause a very severe host-mediated pathology including fever, and hemolysis leading to anemia, hyperbilirubinuria, hemoglobinuria and possible organ failure. In recent years, apparently owing to increased medical awareness and better diagnostic methods, the number of reported cases in humans is rising steadily worldwide. Hitherto unknown zoonotic Babesia spp. are now being reported from geographic areas where babesiosis was not previously known to occur and the growing numbers of travelers and immunocompromised individuals suggest that the frequency of cases in Europe will also continue to rise. Our review is intended to provide clinicians with practical information on the clinical management of this rare, but potentially life-threatening zoonotic disease. It covers epidemiology, phylogeny, diagnostics and treatment of human babesiosis and the potential risk of transfusion-transmitted disease with a special focus on the European situation.

Anaplasma phagocytophilum--a widespread multi-host pathogen with highly adaptive strategies

The bacterium Anaplasma phagocytophilum has for decades been known to cause the disease tick-borne fever (TBF) in domestic ruminants in Ixodes ricinus-infested areas in northern Europe. In recent years, the bacterium has been found associated with Ixodes-tick species more or less worldwide on the northern hemisphere. A. phagocytophilum has a broad host range and may cause severe disease in several mammalian species, including humans. However, the clinical symptoms vary from subclinical to fatal conditions, and considerable underreporting of clinical incidents is suspected in both human and veterinary medicine. Several variants of A. phagocytophilum have been genetically characterized. Identification and stratification into phylogenetic subfamilies has been based on cell culturing, experimental infections, PCR, and sequencing techniques. However, few genome sequences have been completed so far, thus observations on biological, ecological, and pathological differences between genotypes of the bacterium, have yet to be elucidated by molecular and experimental infection studies. The natural transmission cycles of various A. phagocytophilum variants, the involvement of their respective hosts and vectors involved, in particular the zoonotic potential, have to be unraveled. A. phagocytophilum is able to persist between seasons of tick activity in several mammalian species and movement of hosts and infected ticks on migrating animals or birds may spread the bacterium. In the present review, we focus on the ecology and epidemiology of A. phagocytophilum, especially the role of wildlife in contribution to the spread and sustainability of the infection in domestic livestock and humans.

Reservoir competence of wildlife host species for Babesia microti

Competence data will aid understanding of the spread of human babesiosis.

Human babesiosis is an increasing health concern in the northeastern United States, where the causal agent, Babesia microti, is spread through the bite of infected Ixodes scapularis ticks. We sampled 10 mammal and 4 bird species within a vertebrate host community in southeastern New York to quantify reservoir competence (mean percentage of ticks infected by an individual host) using real-time PCR. We found reservoir competence levels >17% in white-footed mice (Peromyscus leucopus), raccoons (Procyon lotor), short-tailed shrews (Blarina brevicauda), and eastern chipmunks (Tamias striatus), and <6% but >0% in all other species, including all 4 bird species. Data on the relative contributions of multiple host species to tick infection with B. microti and level of genetic differentiation between B. microti strains transmitted by different hosts will help advance understanding of the spread of human babesiosis.

Molecular detection of Anaplasma, Bartonella, and Borrelia species in ticks collected from migratory birds from Hong-do Island, Republic of Korea

Bird migration is a recurring annual and seasonal event undertaken by more than 100 species of birds in the southeast Asian and northeast Palearctic regions that pass through or remain for short periods from April to May and September to November at Hong-do Island, Republic of Korea (ROK). A total of 212 ticks (40 Haemaphysalis flava, 12 H. longicornis, 146 Ixodes turdus, 13 I. nipponensis, and 1 I. ornithophila) were collected from 65/2,161 (3.0%) migratory birds consisting of 21 species that were captured from January, 2008, through December, 2009, as part of the Migratory Birds Center, Hong-do bird banding program for studying bird migration patterns. Adult ticks were assayed individually while larvae and nymphs were pooled (1-22 and 1-6 ticks per pool, respectively) into 31 and 65 pools, respectively. Ticks were assayed for zoonotic pathogens by PCR using 16S rRNA, heat shock protein (groEL), and internal transcribed spacer (ITS) gene primers to amplify genera specific for Anapalsma, Bartonella, and Borrelia PCR amplicons. Using the 16S rRNA-based nested PCR, A. phagocytophilum (n=1) was detected in I. nipponensis collected from Zoothera sibirica and A. bovis (n=1) was detected in I. turdus collected from Emberiza chrysophrys. Borrelia turdi 16S rRNA genes (n=3) were detected in I. turdus and I. nipponensis collected from Turdus pallidus and Zoothera aurea. Borrelia spp. 16S rRNA genes (n=4) were detected in Ixodes ticks collected from Emberiza tristrami, T. pallidus, and Z. aurea. The Bartonella grahamii ITS gene (n=1) was detected by nested PCR assay in I. turdus collected from Z. aurea. These results provide insight into the potential role of migratory birds in the dispersal of ticks and associated tick-borne pathogens throughout their ranges in Asia.

Lyme borreliosis spirochetes and spotted fever group rickettsiae in ixodid ticks from Pianosa island, Tuscany Archipelago, Italy

A study on tick fauna and tick-borne pathogens was undertaken in Pianosa, an island in the Tuscany Archipelago that constitutes an important stopping and nesting point for migratory birds. Ticks were removed from feral cats and a few terrestrial birds, and host-seeking ticks were collected by dragging. A total of 89 ticks were found on animals: 57 Ixodes ventalloi Gil Collado, 1936 and 32 Ixodes acuminatus Neumann, 1901. Host-seeking ticks were 354 Hyalomma spp. larvae and 18 Hyalomma spp. adults, identified as Hyalomma marginatum C.L. Koch, 1844 (n=11) and 7 Hyalomma detritum Schulze, 1919 (n=7). A sample of adult ticks was subjected to molecular analyses to look for Rickettsia spp. and Borrelia burgdorferi sensu lato (s.l.). Sequence analysis of the 5S-23S intergenic spacer region and OspA gene of B. burgdorferi s.l.-positive samples showed the presence of Borrelia spielmanii (n=3; 3.7%, 95% confidence interval [CI] 0.08-10.4) and Borrelia valaisiana (n=13; 13.6%, 95% CI 7.0-23.0) in Ixodes ticks from cats and terrestrial birds. Ixodes spp. were also infected by Rickettsia helvetica (n=19; 23.4%, 95% CI 14.7-34.2). Finally, we detected Rickettsia aeschlimannii in 3 out of 12 host-seeking Hyalomma spp. adults tested (25%, 95% CI 5.5-57.2). Our study shows the presence of several tick-borne pathogens in Pianosa. Hyalomma spp. and Ixodes ticks other than I. ricinus seem to be involved in their epidemiological cycle, and birds could contribute to the pathogen dispersal along their migration routes. This is the first finding of B. spielmanii in Italy. We hypothesize the involvement of peridomestic rodents or hedgehogs in its maintenance in Pianosa.

Rickettsiae of spotted fever group, Borrelia valaisiana, and Coxiella burnetii in ticks on passerine birds and mammals from the Camargue in the south of France

Ticks are obligate hematophagous arthropods that have a limited mobility, but can be transported over large geographical distances by wild and domestic mammals and birds. In this study, we analyze the presence of emerging zoonotic bacteria in ticks collected from passerine birds and mammals present in the Camargue, in the south of France, which is a major rallying point for birds migrating from Eurasia and Africa. The presence of Coxiella burnetii, Rickettsia, Borrelia, and Bartonella was examined by real-time PCR on DNA samples extracted from 118 ticks. Rickettsia massiliae was detected in ticks from Passer domesticus, Ri. aeschlimannii in ticks from Acrocephalus scirpaceus and Luscinia megarhynchos, and Borrelia valaisiana in one tick from Turdus merula. In addition, Ri. massiliae, Ri. slovaca, Candidatus Ri. barbariae, and C. burnetii were detected in ticks from dogs, horses, cats, and humans. No Bartonella DNA was detected in these samples. The migratory birds may play a role in the transmission of infectious diseases and contribute to the geographic distribution of Ri. aeschlimannii, Bo. valaisiana, and C. burnetii. The role of birds in spreading Rh. sanguineus ticks infected with Ri. massiliae needs to be clarified by complementary studies. This is the first detection of Candidatus Ri. barbariae in Rh. sanguineus from the south of France.

Bird ticks in an area of the Cerrado of Minas Gerais State, southeast Brazil

In the present study the tick prevalence, mean intensity of infestation and species were recorded on birds captured between January 2009 and December 2010 in the Ecological Station Pirapitinga-ESEC from Minas Gerais State, Brazil. A total of 967 birds, from 15 families and 40 species were captured and 165 (17.1 %) individuals were parasitized by ticks. Of these 160 (97 %) belonged to the order Passeriformes. Five tick species were identified: Amblyomma longirostre (n = 274) was the most common species followed by Amblyomma parvum (n = 43), Amblyomma nodosum (n = 39), Amblyomma ovale (n = 24) and Riphicephalus sanguineus (n = 7). None of 61 unengorged larvae molted to nymph. The mean intensity of infestation was 2.7 ± 2.4 ticks per bird (448 ticks/165 birds) ranging from 1 to 10. Only 19 (11.4 %) birds were infested with one species of tick. The remaining birds were infested by two, three or four species of ticks. Also new hosts for all five ticks were recorded. Only nymphs were recorded throughout the year with two similar peaks during autumn and winter 2009 and 2010.

Tick-borne zoonotic pathogens in ticks feeding on the common nightingale including a novel strain of Rickettsia sp

We examined 77 Ixodes ricinus ticks found on 33 out of 120 common nightingales (Luscinia megarhynchos) sampled in the Czech Republic in 2008 for the presence of Borrelia spirochetes, Anaplasma phagocytophilum, Rickettsia spp., and Babesia spp. We detected Borrelia garinii (in 4% of ticks), A. phagocytophilum (1%), Rickettsia helvetica (3%), a novel strain of Rickettsia sp. (sister taxon of R. bellii; 1%), and Babesia sp. EU1 (1%). Thus, we conclude that nightingales are unlikely to be important reservoir hosts for tick-borne pathogens.

Migratory and carnivorous birds in Brazil: reservoirs for Anaplasma and Ehrlichia species?

In order to investigate new hosts for Anaplasmataceae agents in Brazil, we collected blood samples from 21 wild birds. Using molecular techniques, we detected the presence of Anaplasma phagocytophilum, Ehrlichia chaffeensis, and an Ehrlichia species closely related to Ehrlichia canis in carnivorous avian blood samples. In addition, an Ehrlichia species closely related to an Ehrlichia species found in wild felines in Brazil was also detected in a goose blood sample. Wild birds may play a role as carriers of Anaplasmataceae agents in Brazil.

Importation of Hyalomma marginatum, vector of Crimean-Congo haemorrhagic fever virus, into the United Kingdom by migratory birds

Hyalomma marginatum ticks are an important vector of Crimean-Congo haemorrhagic fever virus which can result in a severe and potentially fatal disease in humans. Given the continued emergence of clinical cases in Eurasia and focalised upsurges of H. marginatum populations in Europe, it seemed prudent to assess the potential of this vector species to be introduced into the United Kingdom. Immature forms of H. marginatum are frequent ectoparasites of passerine birds many of which migrate from Africa to the UK each spring. Incoming birds were inspected for ticks during the spring migration in 2010 and 2011. A total of 68 ticks was collected from 971 birds (29 bird species), 21% (14) of the ticks were identified as H. marginatum. Oenanthe oenanthe (Northern wheatear) and Sylvia communis (Whitethroat) were found to be infested by this tick in both years and with multiple ticks. Single specimens were also removed from Acrocephalus schoenobaenus (Sedge warbler) and Phoenicurus phoenicurus (Common redstart) in 2010. This study provides the first contemporary evidence for substantial importation of this tick species into the UK.

Effect of forest fragmentation on tick infestations of birds and tick infection rates by rickettsia in the Atlantic forest of Brazil

Habitat loss and modifications affect biodiversity, potentially contributing to outbreaks of infectious diseases. We evaluated if the patch sizeinfragmented areas of Atlantic Forest in southeastern Brazil influences the diversity of forest birds and consequently the prevalence of ticks on birds and the rickettsial infection of these ticks. During 2 years, we collected ticks from birds in 12 sites: four small forest patches (80-140 ha), four large ones (480-1,850 ha), and four forest control areas within the much larger Morro do Diabo State Park (approximately 36,000 ha). A total of 1,725 birds were captured (81 species, 24 families), from which 223 birds were infested by 2,339 ticks of the genus Amblyomma, mostly by the species A. nodosum. Bird diversity and richness were higher in larger than smaller forest fragments. The prevalence of ticks on birds was inversely correlated with bird diversity and richness. Among 174 A. nodosum tested for rickettsial infection by polymerase chain reaction, 51 were found to be infected by Rickettsia bellii or Rickettsia parkeri. However, tick infection rates by Rickettsia spp. were not statistically different between forest patch sizes. The higher prevalence of ticks on birds in degraded patches might be caused by a dominance of a few generalist bird species in small patches, allowing an easier transmission of parasites among individuals. It could also be related to more favorable microclimatic conditions for the free-living stages of A. nodosum in smaller forest fragments.The higher burden of ticks on birds in smaller forest fragments is an important secondary effect of habitat fragmentation, possibly increasing the likelihood of Rickettsia contagion.

The importance of Ixodes arboricola in transmission of Rickettsia spp., Anaplasma phagocytophilum, and Borrelia burgdorferi sensu lato in the Czech Republic, Central Europe

Wild birds are known to be a reservoir of infectious disease agents and disseminatory hosts of ticks. The purpose of this work was to obtain information about the occurrence of rickettsial, anaplasmal, and borrelial infections in some ticks that parasitize wild birds in the Czech Republic. A total of 549 subadult ticks of three species Ixodes arboricola (75.0%), Ixodes ricinus (23.1%), and Haemaphysalis concinna (1.8%) were collected from 20 species of birds (Passeriformes). Rickettsiae were detected in 44.0% larvae and 24.5% nymphs of I. arboricola collected from Parus major, Poecile palustris, and Sitta europaea. Rickettsiae-positive I. ricinus larvae (13.7%) were collected from P. major, Cyanistes caeruleus, and S. europaea, and 2.6% of nymphs from Erithacus rubecula and Prunella modularis. Comparison of sequences of a gltA gene fragment with data available in GenBank identified Rickettsia helvetica, a spotted fever rickettsia associated with human infections, and other Rickettsia spp. Anaplasma phagocytophilum was found only in two I. ricinus nymphs collected from E. rubecula and P. major. Infections with Borrelia burgdorferi sensu lato were recorded in 1.3% larvae of I. arboricola acquired from P. palustris and P. major and in 11.8% larvae and 25.0% nymphs of I. ricinus collected from P. major, P. palustris, C. caeruleus, Acrocephalus schoenobaenus, Turdus merula, Carpodacus erythrinus, Sylvia atricapilla, P. modularis, and Phylloscopus collybita. Reverse-line blot hybridization showed infections with Borrelia garinii and Borrelia valaisiana and mixed infections with these two genospecies. This is the first record of a high rate of rickettsial infection in I. arboricola subadult ticks acquired from birds in the Czech Republic and in central Europe. Our study suggests that I. arboricola, P. major, and P. palustris play important roles in circulating rickettsiae.

Ticks (Acari: Ixodidae) infesting wild birds in the Atlantic Forest in northeastern Brazil, with notes on rickettsial infection in ticks

A total of 232 individuals representing 46 species of birds were mist-netted and screened for ticks in a region of the Atlantic Forest, State of Bahia, Brazil. Thirty-eight (16.4%) of these birds representing 17 species were found infested by immature stages of Amblyomma ticks, namely, Amblyomma longirostre (Koch, 1844) (15 larvae and seven nymphs), Amblyomma nodosum (Neumann, 1899) (nine nymphs), Amblyomma calcaratum (Neumann, 1899) (five nymphs), Amblyomma cajennense (Fabricius, 1787) (seven larvae), and Amblyomma parkeri (Fonseca and Aragão, 1952) (four larvae). Overall, 21 larvae and five nymphs collected from birds could not be identified to species and were morphologically identified as Amblyomma spp. Among 13 A. longirostre larvae and two A. parkeri larvae, two individuals of A. longirostre (15.4%) were found infected by Rickettsia amblyommii. This study provides some bird species found infested by A. longirostre, A. parkeri, A. calcaratum, A. nodosum, or A. cajennense for the first time and expands the distribution of R. amblyommii-infected A. longirostre ticks.

Co-circulation of emerging tick-borne pathogens in Middle Germany

From May until October 2007, a total of 658 Ixodes ricinus ticks were collected off birds (189), rodents (273), and vegetation (196) in a certain area of Middle Germany and investigated for infection with Babesia spp., Anaplasma phagocytophilum, and Rickettsia spp. Overall, 13.1% (86/658) of the ticks were infected with at least one pathogen; co-infections occurred in 0.6% (4/658). Babesia spp. specific DNA was detected in 9.7% (64/658) of the ticks, 1.4% (9/658) were infected with A. phagocytophilum, and 2.6% (17/658) harbored rickettsiae. At least two different Rickettsia species were identified: Rickettsia monacensis and Rickettsia helvetica. Our study provides first interesting insights into the circulation and co-circulation of several emerging pathogens not only in ticks parasitizing birds and small mammals as potential reservoirs but also in questing ticks in a single natural habitat.

Coexistence of pathogens in host-seeking and feeding ticks within a single natural habitat in Central Germany

The importance of established and emerging tick-borne pathogens in Central and Northern Europe is steadily increasing. In 2007, we collected Ixodes ricinus ticks feeding on birds (n = 211) and rodents (n = 273), as well as host-seeking stages (n = 196), in a habitat in central Germany. In order to find out more about their natural transmission cycles, the ticks were tested for the presence of Lyme disease borreliae, Anaplasma phagocytophilum, spotted fever group (SFG) rickettsiae, Francisella tularensis, and babesiae. Altogether, 20.1% of the 680 ticks examined carried at least one pathogen. Bird-feeding ticks were more frequently infected with Borrelia spp. (15.2%) and A. phagocytophilum (3.2%) than rodent-feeding ticks (2.6%; 1.1%) or questing ticks (5.1%; 0%). Babesia spp. showed higher prevalence rates in ticks parasitizing birds (13.2%) and host-seeking ticks (10.7%), whereas ticks from small mammals were less frequently infected (6.6%). SFG rickettsiae and F. tularensis were also found in ticks collected off birds (2.1%; 1.2%), rodents (1.8%; 1.5%), and vegetation (4.1%; 1.6%). Various combinations of coinfections occurred in 10.9% of all positive ticks, indicating interaction of transmission cycles. Our results suggest that birds not only are important reservoirs for several pathogens but also act as vehicles for infected ticks and might therefore play a key role in the dispersal of tick-borne diseases.