Two for the price of one: Co-infection with Rickettsia bellii and spotted fever group Rickettsia in Amblyomma (Acari: Ixodidae) ticks recovered from wild birds in Brazil.

The bacterium Rickettsia bellii has been detected in 25 species of ticks in the American continents, but its pathogenic potential is considered as undetermined. A possible role for this species in the phenomenon of transovarial exclusion of pathogenic members of the spotted fever group (SFG) of Rickettsia has been suggested and co-infections with pathogenic species have been reported infrequently in both North and South America. Traditional methods for the molecular detection of rickettsial agents in ticks focus largely on the identification of sequences found in SFG Rickettsia, an approach that may overlook the presence of co-infections with R. bellii. Two novel, species-specific polymerase chain reaction (PCR) assays, targeting the genes encoding the surface cell antigen (Sca), autotransporter proteins sca9 and sca14, were developed and validated for the detection of R. bellii using 150 Amblyomma ticks collected from wild birds in Brazil. Co-infection of R. bellii infected ticks was evaluated using a novel PCR assay targeting the ompA sequence characteristic of SFG Rickettsia. Preliminary species-level identification was achieved by restriction fragment length polymorphism (RFLP) analysis and subsequently confirmed by sequencing of amplicons. Nine out of seventy-three Amblyomma longirostre and one of two Amblyomma calcaratum ticks were shown to be co-infected with R. bellii and Rickettsia amblyommatis, while two out of sixty-seven Amblyomma sp. haplotype Nazaré ticks were recorded as co-infected with R. bellii and the Rickettsia parkeri-like bacterium, strain ApPR. Interestingly, our data represent the first records of R. bellii in association with A. calcaratum and Amblyomma sp. haplotype Nazaré. The novel PCR-RFLP systems reported herein, provide an alternative, rapid and cost-efficient (relative to strategies based on sequencing or real-time PCR), approach to evaluate rickettsial co-infection of ticks, a potentially significant phenomenon that has most likely been underestimated to date.

New host records of Haemaphysalis leporispalustris (Acari: Ixodidae) on birds in Brazil.

Birds are an important component of the life histories and bioecology of a number of tick species and of some tick associated pathogens. An examination of the data concerning bird/tick associations in the Neotropics, showed that the tick Haemaphysalis leporispalustrisis (Packard, 1869) was rarely recorded infesting birds. The current study reports parasitism by H. leporispalustris in wild birds collected from Atlantic rain forest environments in the states of Rio de Janeiro (4LL) and Minas Gerais (17LL, 1NN), Brazil. All ticks were identified morphologically to the genus level; total DNA was extracted from each Haemaphysalis tick and examined by PCR and nucleotide sequencing of fragments of the eukaryotic genes encoding 16S rRNA and 12S rRNA. The bird species Arremon semitorquatus, Corythopis delalandi, Fluvicola nengeta, Troglodytes musculus, and Volatinia jacarina were recorded as hosts for H. leporispalustris for the first time in South America, and Turdus rufiventris represented a new record for Brazil.

Ticks on birds caught on the campus of the Federal Rural University of Rio de Janeiro, Brazil.

The prevalence of parasitic infections, particularly those caused by ectoparasites, may influence the biology and ecology of wild birds. The aim of this study was to investigate occurrences and identify the species of ticks collected from wild birds caught on the campus of the Federal Rural University of Rio de Janeiro. The birds were caught using mist nets between October 2009 and December 2010. In total, 223 birds were caught, represented by 53 species and 19 families in nine orders. Nineteen birds (n = 7 species) were parasitized by immature ticks (prevalence of 8.5%). Forty-four ticks were collected, of which 23 were nymphs and 21 were larvae. There were associations between parasitism by ticks and non-Passeriformes birds, and between parasitism and ground-dwelling birds, which was possibly due to the presence (or inclusion among the captured birds) of Vanellus chilensis (Charadriiformes: Charadriidae). All the nymphs collected were identified as Amblyomma cajennense. In general terms, we must emphasize that wild birds in the study area may play the role of dispersers for the immature stages of A. cajennense, albeit non-preferentially.

Ticks on birds caught on the campus of the Federal Rural University of Rio de Janeiro, Brazil / Carrapatos em aves capturadas no campus da Universidade Federal Rural do Rio de Janeiro, Brasil

The prevalence of parasitic infections, particularly those caused by ectoparasites, may influence the biology and ecology of wild birds. The aim of this study was to investigate occurrences and identify the species of ticks collected from wild birds caught on the campus of the Federal Rural University of Rio de Janeiro. The birds were caught using mist nets between October 2009 and December 2010. In total, 223 birds were caught, represented by 53 species and 19 families in nine orders. Nineteen birds (n = 7 species) were parasitized by immature ticks (prevalence of 8.5%). Forty-four ticks were collected, of which 23 were nymphs and 21 were larvae. There were associations between parasitism by ticks and non-Passeriformes birds, and between parasitism and ground-dwelling birds, which was possibly due to the presence (or inclusion among the captured birds) of Vanellus chilensis (Charadriiformes: Charadriidae). All the nymphs collected were identified as Amblyomma cajennense. In general terms, we must emphasize that wild birds in the study area may play the role of dispersers for the immature stages of A. cajennense, albeit non-preferentially.

A prevalência das infecções parasitárias e em particular, aquelas causadas por ectoparasitos, pode influenciar na biologia e ecologia das aves silvestres. O objetivo do estudo foi investigar a ocorrência e identificar as espécies de carrapatos coletadas em aves silvestres capturadas no campus da Universidade Federal Rural do Rio de Janeiro. As aves foram coletadas em rede-de-neblina durante o período de outubro de 2009 a dezembro de 2010. No total foram capturadas 223 aves representadas por 53 espécies, 19 famílias em 9 ordens. Parasitismo por formas imaturas de carrapatos, foram encontradas em 19 aves (n = 7 espécies) correspondendo a uma prevalência de 8,5%. Foram coletados 44 carrapatos onde 23 estavam em estágio de ninfa e 21 em estágio de larva. Houve associação entre o parasitismo por carrapatos e aves não Passeriformes e entre o parasitismo e aves de hábitos terrestres capturadas, que se deu possivelmente pela presença (ou inclusão da captura) de Vanellus chilensis (Charadriiforme: Charadriidae). Todas as ninfas coletadas foram identificadas como Amblyomma cajennense. De modo geral, devemos ressaltar que aves silvestres da área estudada podem exercer papel de dispersoras, ainda que não preferenciais, para estágios imaturos de A. cajennense.