Quantification of Leishmania infantum DNA in females, eggs and larvae of Rhipicephalus sanguineus

<p/> <p>Background</p> <p><it>Leishmania infantum </it>is a widespread parasite that affects dogs and humans worldwide. It is transmitted primarily by phlebotomine sand flies, but recently there has been much discussion on the role of the brown dog tick, <it>Rhipicephalus sanguineus</it>, as a potential vector for this protozoan. Recent laboratory and field investigations have contributed to this hypothesis, but a proof of the vector capacity of <it>R. sanguineus </it>has yet to be provided. Following a recent study suggesting that <it>L. infantum </it>passes transovarially from the female tick to her progeny the current study provides new evidence of the transovarial transmission of <it>L. infantum </it>in <it>R. sanguineus</it>.</p> <p>Methods</p> <p>Engorged females of <it>R. sanguineus </it>were collected from the environment in a dog shelter of southern Italy, where canine leishmaniosis is endemic. In the laboratory, 97 females that successfully laid eggs, their eggs and the originated larvae were subjected to DNA extraction and then tested by a TaqMan-based real time PCR targeting a fragment of the kinetoplast DNA (kDNA) of <it>L. infantum</it>.</p> <p>Results and conclusions</p> <p><it>L. infantum </it>kDNA was detected in engorged females, their eggs and originating larvae, with a parasite load ranging from 1.8 × 10^-4to 10.0 × 10⁰. Certainly, the current study provides further evidence on the passage of <it>L. infantum </it>from <it>R. sanguineus </it>females to their offspring. The observation of promastigote forms in larvae is necessary to definitively confirm this hypothesis, which would raise interesting questions about the possible role of ticks in the maintenance of <it>L. infantum </it>infection among dogs in certain areas.</p

Detection of Leishmania infantum DNA mainly in Rhipicephalus sanguineus male ticks removed from dogs living in endemic areas of canine leishmaniosis

Background: Sand flies are the only biologically adapted vectors of Leishmania parasites, however, a possible role in the transmission of Leishmania has been proposed for other hematophagous ectoparasites such as ticks. In order to evaluate natural infection by Leishmania infantum in Rhipicephalus sanguineus ticks, taking into account its close association with dogs, 128 adult R. sanguineus ticks removed from 41 dogs living in endemic areas of canine leishmaniosis were studied. Methods: Individual DNA extraction was performed from each tick and whole blood taken from dogs. Dog sera were tested for IgG antibodies to L. infantum antigen by ELISA and L. infantum real-time PCR was performed from canine whole blood samples and ticks. Results: Leishmania infantum PCR was positive in 13 ticks (10.1%) including one female, (2.0%) and 12 males (15.2%), and in only five dogs (12.2%). Male ticks had a significantly higher infection rate when compared to female R. sanguineus. The percentage of L. infantum seroreactive dogs was 19.5%. All but two PCR positive dogs were seroreactive. Leishmania infantum PCR positive ticks were removed from seropositive and seronegative dogs with a variety of PCR results. Conclusions: This study demonstrates high prevalence of L. infantum DNA in R. sanguineus ticks removed from L. infantum seropositive and seronegative dogs. The presence of L. infantum DNA was detected mainly in male ticks possibly due to their ability to move between canine hosts and feed on several canine hosts during the adult life stage. Additional studies are needed to further explore the role of R. sanguineus ticks and in particular, male adults, in both the epidemiology and immunology of L. infantum infection in dogs in endemic areas

Illegal Wildlife Trade: A Gateway to Zoonotic Infectious Diseases

The illegal wildlife trade (IWT) is a criminal practice bringing several ecological and public health consequences, such as the spreading of zoonotic pathogens and/or the introduction of exotic species of animals into new geographical areas. Here, we discuss potential risks of IWT on the spreading and emergence of zoonotic pathogens

Ticks infesting humans in Italy and associated pathogens

Background: Ticks may transmit a large variety of pathogens, which cause illnesses in animals and humans, commonly referred to as to tick-borne diseases (TBDs). The incidence of human TBDs in Italy is underestimated because of poor surveillance and the scant amount of studies available. Methods. Samples (n = 561) were collected from humans in four main geographical areas of Italy (i.e., northwestern, northeastern, southern Italy, and Sicily), which represent a variety of environments. After being morphologically identified, ticks were molecularly tested with selected protocols for the presence of pathogens of the genera Rickettsia, Babesia, Theileria, Candidatus Neoehrlichia mikurensis, Borrelia and Anaplasma. Results: Ticks belonged to 16 species of the genera Argas, Dermacentor, Haemaphysalis, Hyalomma, Ixodes and Rhipicephalus, with Ixodes ricinus (59.5%) being the species most frequently retrieved, followed by Rhipicephalus sanguineus sensu lato (21.4%). Nymphs were the life stage most frequently retrieved (41%), followed by adult females (34.6%). The overall positivity to any pathogen detected was 18%. Detected microorganisms were Rickettsia spp. (17.0%), Anaplasma phagocytophilum (0.8%), Borrelia afzelii (0.5%), Borrelia valaisiana (0.3%), C. N. mikurensis (0.5%) and Babesia venatorum (0.6%). Conclusions: Results indicate that people living in the Italian peninsula are at risk of being bitten by different tick species, which may transmit a plethora of TBD causing pathogens and that co-infections may also occur. © 2014 Otranto et al.; licensee BioMed Central Ltd

Caracterização agronômica de novos genótipos de mamoeiro na Chapada do Apodi.

O mamoeiro (Carica papaya L.) possui expressiva importância econômica para o Brasil, destacando-se como segundo maior produtor mundial. Em 2012 o país produziu 1.517.696 toneladas de mamão (FAO, 2012). No Brasil o mamoeiro é cultivado na quase totalidade do seu território, merecendo destaque os estados da Bahia, Espirito Santo, Ceará e Rio Grande do Norte, que são responsáveis por 87,35% da produção nacional (IBGE, 2013)