Changes in the physiological, hematological and parasitological parameters of Dorper sheep in relation to residual feed intake and confinement environment.

The selection of animals with greater feed efficiency has unknown parasitological and physiological parameters when confined in full sun or shade. Thus, we aimed to assess the effect of residual feed intake (RFI) and the confinement environment on the hematological, parasitological and physiological parameters in male Dorper sheep (n = 60; 30 with positive RFI and 30 with negative RFI) distributed in 2 confinement environments (full sun and shade), in a 2 × 2 factorial scheme, with 15 animals for treatment. Animals kept in the shade showed an increase (P < 0.05) of erythrocytes, hemoglobin and albumin. Animals kept in full sun showed higherOocysts gamma glutamyltransferase, direct bilirubin, transaminase aspartate and respiratory rate (P<0.05). There was a higher incidence of Eimeria spp oocysts in RFI negative animals (P<0.05). Positive RFI animals increased respiratory rate (P<0.05). The RFI did not influence the blood parameters of Dorper sheep, however, it had an effect on respiratory rate and presence of Eimeria spp. oocysts. Thermal environment promoted changes in blood parameters and the physiological parameters of Dorper sheep.

Seroepidemiological survey on Leptospira spp. infection in wild and domestic mammals in two distinct areas of the semi-arid region of northeastern Brazil.

Leptospirosis is a bacterial zoonotic disease that causes severe reproductive problems in livestock and generates economic losses for farmers. This study aimed to determine the seroprevalence of anti-Leptospira antibodies in small mammals, both wild and domestic, in two distinct areas of the semi-arid region of northeastern Brazil: the National Park of Serra das Confusões (NPSC), state of Piauí, a preserved area; and rural areas in the municipalities of Petrolina and Lagoa Grande, state of Pernambuco, non-preserved areas. Serum samples were evaluated using the microscopic agglutination test (MAT). Approximately 4% (6/152) of the wild animals were positive, all of them in the non-preserved area. Overall, the seroprevalence rates among goats and sheep were 13.4 (77/576) and 4.6% (24/518), respectively, confirmed in both areas. The seroprevalence rates in dogs and cats were 5.6 (10/180) and 4.7% (2/43) and were determined only in the non-preserved area. The risk factors associated with Leptospira spp. infection were as follows: ages of 1-3 and > 3 years for goats and sheep, region (preserved area) for goats, intensive management system for sheep, and region (non-preserved area) for dogs and wildlife. The present study confirmed the presence of circulation of Leptospira spp. in both of these areas of the Caatinga biome, as well as a variety of serotypes in these areas.

Parasitism on domestic cats by Amblyomma auricularium and serological evidence of exposure to Rickettsia amblyommatis.

The domestic cat is not considered a primary host for any specific tick species; however, it can be affected by some Ixodidae species, such as Rhipicephalus sanguineus sensu lato and Amblyomma spp. The study reports parasitism by Amblyomma auricularium and the detection of anti-Rickettsia spp. antibodies in domestic cats from a rural property in the Afrânio municipality, Pernambuco, Brazil. Amblyomma auricularium (24 nymphs, six females, and four males) and Amblyomma sp. (42 larvae) parasitized three cats, and 73 free-living ticks were captured in armadillo burrows: A. auricularium (36 nymphs, six females, five males) and Amblyomma sp. (26 larvae). Blood samples from cats were collected and the obtained plasma were subjected to indirect immunofluorescence assay (IFA) to detect antibodies against Rickettsia antigens. Thus, anti-Rickettsia spp. antibodies were determined (titers ranging from 128 to 512) and showed a predominant antibody response to Rickettsia amblyommatis or a very closely related genotype. This study reports the first infestation of nymphs and adults of A. auricularium on cats in a new area of occurrence in the semi-arid region of Northeastern Brazil and reports for the first time the presence of anti-Ricketsia antibodies in cats in the region, with R. amblyommatis as the probable infectious agent.

Exposure of small ruminants and humans to Coxiella burnetii in the semi-arid region of Northeastern Brazil.

Q fever is a zoonotic disease caused by the obligate intracellular pathogen Coxiella burnetii, for which domestic ruminants are the primary source of infection in humans. Herein, we investigated the presence of C. burnetii in humans, sheep, and goats in the semi-arid region of northeastern Brazil. The presence of anti-C. burnetii antibodies was surveyed using indirect immunofluorescence assay, and detection of C. burnetii DNA was performed by polymerase chain reaction (PCR). Anti-C. burnetii antibodies were detected in 60% of farms, 4.8% of goats, 1.5% of sheep, and 4.5% of human samples. PCR was positive in 18.9% of blood samples, 7.7% of milk samples, and 7.7% of vaginal mucus samples. A DNA sequence of a C. burnetii DNA sample extracted from the goat vaginal mucus showed 99.2-99.4% nucleotide identity with other strains previously reported in Brazil. These results indicate that C. burnetii is present in the surveyed area, where it poses a risk to both public and animal health. These findings indicate an urgent need for educative actions to protect population, as well as better training of veterinarians to detect and report Q fever.

Hemoplasmas in wild rodents and marsupials from the Caatinga Biome, Brazil.

A total of 231 blood samples from wild mammals belonging to the orders Rodentia (n = 142) and Didelphimorphia (n = 89) were screened by real-time PCR assay (qPCR), being six Rhipidomys sp., 118 Thrichomys laurentius, nine Rattus rattus, four Kerodon rupestris, five Necromys lasiurus, 42 Didelphis albiventris and 47 Monodelphis domestica. Results using qPCR showed that 32 of the total 231 (13.85 %) samples were positive for hemoplasma sequences of the 16S rRNA gene. Sequences from two D. albiventris showed 99.77-99.89 % identity with 'Candidatus Mycoplasma haemoalbiventris' and 99.09 % with 'Candidatus Mycoplasma haemodidelphidis', respectively. Furthermore, one M. domestica and five T. laurentius showed 99.72-99.77 % identity with Mycoplasma sp., and one K. rupestris showed 98.13 % identity with 'Candidatus Mycoplasma haematohydrochaerus'; and from two Rattus rattus showed 99.65-99.89 % identity with Mycoplasma sp. and 'Candidatus Mycoplasma haemomuris'. The 23S rRNA gene sequences obtained from the two D. albiventris showed 100 % identity with 'Ca. M. haemoalbiventris' whereas the sequences from the R. rattus showed only 85.31 % identity with 'Candidatus Mycoplasma haematohydrochaerus'. Two T. laurentius and one K. rupestris showed 84.66-92.97 % identity with 'Candidatus Mycoplasma haemosphiggurus'. Based on phylogenetic and Neighbor-Net network analyses of the 16S and 23S rRNA genes, potential novel species are described. In addition, 'Ca. M. haemoalbiventris' was detected in Didelphis albiventris, and Mycoplasma sp. was detected in Rattus sp. rodents from the Caatinga biome, Brazil.

Occurrence of Babesia and Anaplasma in ruminants from the Catimbau National Park, Semiarid Region of Northeast Brazil.

Babesiosis and Anaplasmosis are diseases associated with economic losses; ticks and blood-sucking flies are important zoonotic vectors and reservoirs. This study aimed to investigate the presence of anti-Babesia spp. and anti-Anaplasma marginale antibodies using enzyme-linked immunosorbent assay (ELISA), in ruminants at the Catimbau National Park. Blood samples were collected from 119 sheep, 119 goats, and 47 cattle. Rhipicephalus microplus ticks were collected from cattle. ELISA showed seropositivity of 34% (16/47), 20.3% (24/119), and 16% (19/119) for anti-Babesia bovis; 34% (16/47), 15.2% (18/119), and 9% (7/119) for anti-Babesia bigemina; and 34% (16/47), 35.6% (42/119), and 17% (20/119) for anti-A. marginale antibodies in cattle, goats, and sheep, respectively. The information collected using an epidemiological questionnaire showed that mostly are breed in a semi-intensive system, with access to Caatinga vegetation. The circulation of B. bovis, B. bigemina, and A. marginale was confirmed. Thus, based on the prevalence, this suggests this is an enzootic instability area and is prone to outbreaks.

Molecular detection and characterization of Bartonella spp. in small mammals in the Amazonia and Cerrado biomes, midwestern Brazil.

Although Bartonella spp. have been worldwide described in rodents and bats, few studies have reported these agents in marsupials. The present work aimed to investigate the occurrence and genetic diversity of Bartonella in small mammals (rodents, marsupials, and bats) and associated ectoparasites in two ecoregions (Amazonia and Cerrado biomes) in midwestern Brazil. For this purpose, DNA samples from 378 specimens of small mammals (128 rodents, 111 marsupials, and 139 bats) and 41 fleas (Siphonaptera) were screened for the Bartonella genus employing a quantitative real-time PCR assay (qPCR) based on the nuoG (nicotinamide adenine dinucleotide dehydrogenase gamma subunit) gene. Then, positive samples in qPCR were submitted to conventional PCR (cPCR) assays targeting the gltA, ftsZ, and rpoB genes. One (0.78 %) rodent, 23 (16.54 %) bats, and 3 (7.31 %) fleas showed positive results in the qPCR for Bartonella sp. After cPCR amplification and sequencing, 13 partial Bartonella DNA sequences of the following genes were obtained only from bats´ blood samples: 9 gltA (citrate synthase), 3 ftsZ (cell division protein), and 1 rpoB (RNA polymerase beta subunit). The maximum likelihood inference based on the gltA gene positioned the obtained sequences in three different clades, closely related to Bartonella genotypes previously detected in other bat species and bat flies sampled in Brazil and other countries from Latin America. Similarly, the ftsZ sequences clustered in two different clades with sequences described in bats from Brazil, other countries from Latin America, and Georgia (eastern Europe). Finally, the Bartonella rpoB from a specimen of Lophostoma silvicolum clustered with a Bartonella sp. sequence obtained from a Noctilio albiventris (KP715475) from French Guiana. The present study provided valuable insights into the diversity of Bartonella genotypes infecting bats from two ecoregions (Amazonia and Cerrado) in midwestern Brazil and emphasized that further studies should be conducted regarding the description and evaluation of different lineages of Bartonella in wild small mammals and their ectoparasites in different Brazilian biomes.

Ticks parasitizing cold-blooded animals from three different Brazilian biomes; with note for males of Amblyomma rotundatum.

Ticks parasitize a wide variety of wild animals, including amphibians and reptiles. In addition to the possibility of microorganism transmission to these hosts, ticks can also cause severe bleeding, and high parasitism can lead to death. Therefore, knowing the diversity of ticks parasitizing amphibians and reptiles is important for conservation and preservation measures for these vertebrates. In the present study, we report parasitism by ticks in amphibians and reptiles from different Brazilian biomes (Amazon, Caatinga, Cerrado and Atlantic Forest). Ticks were collected from amphibians and reptiles deposited from the Herpetological Collection of the Federal University of Maranhão (UFMA), São Luís (Maranhão State), the State University Santa Cruz (UESC), Ilhéus (Bahia State), and the Federal University of São Francisco Valley (Univasf), Petrolina (Pernambuco State). Additionally, ticks were collected from amphibians and reptiles captured and road-killed in the Amazon biome, at Maranhão and Amapá States. Specimens of ticks were photographed under a Zeiss stereomicroscope (5.1 zoom). Map with the locations were made using the Qgis program. Overall, 1973 specimens of amphibians and reptiles were examined. A total of 927 ticks were collected: 98 larvae, 421 nymphs and 408 adults. Six species of ticks were identified: Amblyomma rotundatum and Amblyomma dissimile the most frequent, and Amblyomma cajennense sensu stricto, Amblyomma sculptum, Amblyomma nodosum and Amblyomma humerale, occasionally. Surprisingly, a total of twelve males of A. rotundatum were collected. Here we report new records of association between cold-blooded animals and ticks and reinforce the absence of A. dissimile in the Caatinga, Cerrado and Atlantic Forest biomes. Additionally, we report new records of A. rotundatum males on reptiles in the Amazon biome. This last record allows us to speculate about a possible association of A. rotundatum males with reptiles and the Amazon biome.

Patterns and drivers of Human Visceral Leishmaniasis in Pernambuco (Brazil) from 2007 to 2018.

Visceral leishmaniasis (VL) is the second most common protozoosis that affects people around the world. The aim of this study is to understand how environmental and socioeconomic factors, as well as VL control and surveillance interventions, influence the spread and detection of VL cases in Pernambuco state (Brazil). A novel model was developed to analyze cases of VL between 2007 and 2018, enabling the quantification of the association of these variables with two processes: the probability of "invasion" (emergence of new cases) at municipalities by VL, and the probability of detecting cases not reported in municipalities that have already been invaded. Pernambuco state identified 1,410 cases of VL between 2007 and 2018, with an average of 128 cases per year and average incidence of 1.28/100 thousand people. These cases were distributed in 77.1% (142/184) of the municipalities, and 54.8% (773/1,410) of them were autochthonous. Our model reveals that the proportion of agriculture was positively associated with VL invasion probability. We also find that municipalities that are closer to notification centers and/or that have received technical training and support tend to have higher detection rates of VL cases. Taken together, these results suggest that a municipality with almost no agriculture and that received technical training, located close to a notification center, is unlikely to be invaded if no cases have ever been detected. On the other hand, a municipality that is far from the notification center, with no technical training, with a large agricultural area might have already been invaded but the surveillance system might have routinely failed to detect VL cases due to low detection probability. By disentangling the processes of invasion and detection, we were able to generate insights that are likely to be useful for the strategic allocation of VL prevention and control interventions.

Serological Evidence Supporting the Occurrence of Ehrlichia chaffeensis or a Closely Related Species in Brazilian Dogs.

Ehrlichia chaffeensis is a tick-borne bacterium that causes human monocytotropic ehrlichiosis, an emerging life-threatening disease in humans transmitted by Amblyomma americanum. Although most studies have reported bacterial isolations and clinical cases in the United States, their occurrence is not restricted to North America. Some studies in the Southern Cone of South America have molecularly detected a close phylogenetic relative of E. chaffeensis in ticks and wild mammals. Even so, many gaps must be filled to confirm the presence of this agent in the region. To add new data on this issue, we report the first detection of specific anti-E. chaffeensis antibodies in dogs collected from all regions of Brazil. By means of IFA and ELISA with crude and specific antigens of E. chaffeensis, sera from 1134 dogs were analyzed. Serological analyses using ELISA showed nine (0.7%) seropositive dogs, with seven of them exhibiting IFA titers ranging from 160 to 5120. All regions of Brazil had at least one seropositive dog. Our results support the evidence for the occurrence of E. chaffeensis in South America. As dogs have a close relationship with humans, they can be used as an environmental sentinel for these infections because they can act as a bridge to human parasitism or infection with ehrlichial agents.

Q fever and coxiellosis in Brazil: an underestimated disease? A brief review.

Q fever, caused by the γ-proteobacterium Coxiella burnetii, is a zoonosis of great importance and global impact. This agent has high transmissibility and can spread over long distances via wind, in which a small number of aerosolized particles are needed to infect susceptible hosts. The clinical diagnosis of Q fever is difficult owing to the variety of clinical signs shared with other diseases. In Brazil, studies related to C. burnetii are constantly being conducted, and this review aims to increase the number of approaches already studied, leading to the following question: is Q fever an unknown, neglected disease, or does it have a focal occurrence in certain areas (exotic/rare) in the country?

Epidemiological profile and lethality of visceral leishmaniasis/human immunodeficiency virus co-infection in an endemic area in Northeast Brazil.

INTRODUCTION: The association of visceral leishmaniasis (VL) and human immunodeficiency virus (HIV) infection is a concern worldwide, and this co-infection is linked to increased lethality. The Northeast is the region that mostly reports cases of VL in Brazil. The knowledge of risk factors associated with VL/HIV co-infection and its impact on lethality is extremely important. METHODS: The present study analyzed the epidemiologic features of cases with VL/HIV co-infection in the state of Pernambuco, Northeast of Brazil, from 2014 to 2018. RESULTS: There were 858 and 11,514 reported cases of VL and HIV infection, respectively. The average incidences of VL and HIV infection were 1.82 and 24.4/100,000 inhabitants, respectively. Of all reported cases of VL, 4.9% (42/858) also had HIV infection. There was an inverse spatial association between VL and HIV infection incidences. The lethality rates of VL, HIV infection, and co-infection were 9.9%, 26.1%, and 16.6%, respectively. Most of the patients were males and lived in urban areas. The cases of VL mostly occurred in children aged below 10 years, whereas the cases of HIV infection and VL/HIV co-infection were primarily observed in adults between 20 years and 39 years old. CONCLUSIONS: We defined the profile and areas with most cases of co-infection and found that the lethality of VL with co-infection increased in the current period. These findings contribute to applying efforts with a greater focus in these identified populations to prevent future deaths.

New Species of Chiggers (Trombidiformes: Trombiculidae and Leeuwenhoekiidae) From the Conservation Unit Parque Nacional da Serra das Confusões, Brazil.

The Piauí State, Brazil, has never had its chigger fauna recorded. In this study, we examined chiggers collected on marsupials, rodents, and lizards from the conservation unit Parque Nacional da Serra das Confusões (PNSC). Herein we describe four new species, Paraguacarus klompenin. sp., Neoschoengastia ochoain. sp., Quadraseta welbournin. sp., and Susa bauchanin. sp. Furthermore, an additional seven species are reported: Eutrombicula alfreddugesi (Oudemans, 1910), Microtrombicula brachytrichiaBrennan, 1971, Microtrombicula rhipidomysiGoff, Whitaker and Dietz, 1983, Parascoschoengastia aemulata (Brennan and Jones, 1964), Parasecia validaBrennan, 1969, Pseudochoengastia petrolinensis Jacinavicius, Bassini-Silva and Barros-Battesti 2019, and Quadraseta flochi (Brennan and Jones, 1960). This is the first report of chiggers in Piauí State, which includes one of the most biodiverse areas in the Caatinga biome and is of particular importance to conservation. The genera Paraguacarus Goff and Whitaker, 1984 and Susa Audy and Nadcharam, 1960 are reported here for the first time to Brazil.

Serological evidence of Rickettsia in horses from a semi-arid Brazilian region.

Brazilian spotted fever (BSF) is a common tick-borne disease caused by Rickettsia rickettsii. Horses are the primary hosts of the main vector, Amblyomma sculptum, and are considered efficient sentinels for circulation of Rickettsia. Therefore, the aim of this study was to detect antibodies reactive to R. rickettsii antigens in horses from a non-endemic area in the north-central region of Bahia state, Brazil. Blood samples and ticks were collected from 70 horses from the municipalities of Senhor do Bonfim, Antônio Gonçalves, Pindobaçu, and Campo Formoso. The sera obtained were tested by an indirect immunofluorescence assay to detect anti-Rickettsia antibodies. Overall, 5.7% (4/70) of the horses reacted to R. rickettsii antigens. Ticks were collected from 18.6% (13/70) of the horses and were identified as A. sculptum and Dermacentor nitens. Despite being a non-endemic area, seropositive animals were identified in our study, suggesting circulation of rickettsial agents in the region. This is the first serological survey of this agent in horses from the north-central region of Bahia, and further studies are needed to understand the epidemiology of BSF in these locations.

Comparison of serological and molecular tests to investigate Leishmania spp. infections in stray dogs from an area of intense visceral leishmaniasis transmission in Brazil.

The aim of this study was to investigate the level of exposure to Leishmania infection in stray dogs in an area of intense visceral leishmaniasis transmission in the state of Pernambuco, Brazil. Blood samples from 178 dogs were analyzed using serological and molecular assays: rapid immunochromatographic test (ICT), enzyme-linked immunosorbent assay (ELISA), immunofluorescence antibody test (IFAT), and conventional and quantitative polymerase chain reaction (cPCR and qPCR). Positivity values obtained with serological tests were 71.4% (127/178), 70.2% (125/178), and 50.6% (90/178) using ICT, ELISA, and IFAT, respectively, with 38.8% (69/178) of the dogs were simultaneously positive for all three tests. The positivity values obtained with cPCR and qPCR were 20.2% (36/178) and 38.8% (69/178), respectively, with 11.8% (21/178) testing positive in both molecular assays. Overall, 87.1% (155/178) were positive for anti-Leishmania spp. antibodies and/or Leishmania spp. DNA. Positivity to one or more tests was statistically associated with lymphadenomegaly, skin lesions, lymphocytosis, anemia and hyperproteinemia. The results of this study revealed a high level of exposure to Leishmania in stray dogs in an area of intense human visceral leishmaniasis transmission, suggesting that dogs play a role as reservoirs in the transmission cycle of this zoonosis.

Rickettsial infection in free-ranging capybaras (Hydrochoerus hydrochaeris) and their ticks (Acari, Ixodidae) in the Caatinga and Atlantic forest biomes, Northeastern Brazil.

Caatinga and Atlantic Forest are Brazilian biomes threatened by anthropogenic disturbances, which are a serious threat to biodiversity and favor the emergence of zoonotic pathogens. Capybara populations are increasingly present in urban and rural areas due to the loss of their natural habitats. There are no studies on the rickettsial infection in these rodents in Northeastern Brazil, although there are case records of Brazilian Spotted Fever (BSF) in this region. In this context, we evaluated rickettsial infection in capybaras and their ticks in four areas of the Atlantic Forest and Caatinga biomes in Northeastern Brazil. Blood sera from 21 capybaras were tested by indirect immunofluorescence assay (IFA) using Rickettsia rickettsii, R. parkeri, and R. amblyommatis antigens. Blood samples and ticks (Amblyomma sp., Amblyomma dubitatum and Amblyomma sculptum) were tested by PCR, targeting a fragment of the rickettsial gltA gene and R. bellii primers. Overall, 15 out of 21 capybaras (71.4%) reacted positively (titer ≥64) to at least one of the three Rickettsia antigens tested, with final titers ranging from 64 to 1024. No rickettsial DNA was found in capybara blood samples. Rickettsial DNA was detected in 22 of 31 adult tick pools using gltA gene, being all nine pools of A. sculptum and 16 of the 19 of A. dubitatum, but all samples were negative to R. bellii specific primers. All attempts to sequence the amplicon were unsuccessful, indicating a possible low rickettsial load in the tick samples. The present study reports for the first time the serological evidence of Rickettsia spp. infection in free-ranging capybaras and suggest the rickettsial infection in A. sculptum and A. dubitatum in the Caatinga and Atlantic Forest biomes in Northeastern Brazil.

Spatial analysis and epidemiological profile of visceral leishmaniasis, northeastern Brazil: A cross-sectional study.

Most visceral leishmaniasis (VL) cases reported in Brazil are from the northeast region, where the disease is strongly linked to poverty. In spite of the still existing inequalities, many social improvements were achieved in the past decades in this region, but the possible impact of these improvements on VL remains poorly investigated. We conducted a cross-sectional study coupled with a spatial analysis of VL cases notified in northeastern Brazil from 2007 to 2017. In total, 21,703 cases were reported during this period, with an annual incidence of 3.6 cases per 100,000 inhabitants. Children under 10 years old and males were more affected, and most cases were from urban areas. Living in municipalities situated in the Cerrado, Amazon or, to a lesser extent, in the Caatinga biomes was a risk factor for VL. This study indicates that the epidemiological profile of VL patients remained unchanged in northeastern Brazil, suggesting that social improvements achieved in this region were not enough to mitigate the risk of this disease among the most affected populations.

Tick-borne pathogens in dogs, wild small mammals and their ectoparasites in the semi-arid Caatinga biome, northeastern Brazil.

Caatinga is a biome exclusive to the semiarid zone of Brazil, where studies on ticks and tick-borne diseases are scarce. Herein, we investigated the occurrence of Rickettsia, Ehrlichia, and Coxiella in wild mammals, domestic dogs and their ectoparasites using molecular and serological techniques. During 2014-2016, blood samples and ectoparasites were collected from 70 small mammals (51 rodents, 18 marsupials, 1 wild canid) and 147 domestic dogs in three areas of the Caatinga. Through serological analyses of domestic dogs of the three areas, 8 to 11 % were seropositive for Rickettsia rickettsii, 9 to 37 % for Rickettsia amblyommatis, 61 to 75 % for Ehrlichia canis, and 0-5% for Coxiella burnetii. All wild mammals were seronegative for Rickettsia spp. and C. burnetii, except for one rodent (Wiedomys pyrrhorhinos) and one marsupial (Didelphis albiventris) that were seroreactive to C. burnetii, one wild canid (Cerdocyon thous) for R. amblyommatis, and two Rattus rattus for Rickettsia spp. Through PCR targeting DNA of Rickettsia, Ehrlichia or Coxiella, all blood samples were negative, except for the presence of Ehrlichia canis DNA in 8.8 % of the domestic dogs, and a recently reported novel agent, Ehrlichia sp. strain Natal, in one marsupial (Gracilinanus agilis). A total of 222 ticks, 84 fleas, and six lice were collected. Ticks were mostly Rhipicephalus sanguineus sensu lato, some Ixodes loricatus, Ornithodoros rietcorreai, Haemaphysalis sp., and Amblyomma spp.; fleas were Ctenocephalides felis felis, Pulex sp. and Polygenis (Polygenis) bohlsi jordani; and lice were Polyplax sp. and Gyropus sp. Through molecular detection of microorganisms, 9% of C. felis felis contained Rickettsia felis, 20 % of A. auricularium contained R. amblyommatis and 13 % of A. parvum contained 'Candidatus Rickettsia andeanae', whereas Ehrlichia canis DNA was detected in at least 6% of the R. sanguineus s.l. from one area. We report a variety of ectoparasites infesting small mammals and domestic dogs in the Caatinga biome, where these ectoparasites probably act as vectors of rickettsiae, ehrlichial agents (E. canis and Ehrlichia sp. strain Natal) and C. burnetii. Our results highlight to the potential risks of human infection by these tick-borne agents in the Caatinga biome.

Canine leishmaniasis in the semi-arid region of Pernambuco, northeastern Brazil: epidemiology, factors associated with seropositivity and spatial analysis.

This study aimed to determine the seroprevalence, factors associated with seropositivity to Leishmania infection in dogs and spatial analysis in six municipalities in the semiarid region of Pernambuco, Brazil. Blood samples were collected from 462 dogs, 77 in each municipality, and used for serological analysis [dual path platform (DPP®) and enzyme-linked immunosorbent assay (ELISA)]. Clinical signs of dogs were evaluated and associated factors for Leishmania infection were analyzed using robust Poisson regression model. A seroprevalence of 42.8% (198/462, IC: 95% = 38.6%-47.6%) was detected in dogs that tested positive in both tests, ranging from 29.8% to 55.8%, with higher prevalence in the municipality of Cabrobó (55.8%; P = 0.006). About 67% (132/198) of the seropositive dogs showed one or more clinical signs suggestive of canine leishmaniasis (CanL), such as lymphadenomegaly, skin lesions and conjunctivitis, which were associated with seropositivity. High seroprevalence levels were identified in urban and rural areas in all the municipalities, and the buffer for sand flies around cases covered almost these entire areas. Spatial analysis revealed a significant cluster, showing a relative risk of 1.88 in the urban area of Cabrobó. The higher density of seropositive dogs in urban areas indicates the need effective control measures against CanL to prevent the emergence of canine and human diseases.

Serological detection and risk factors for equine piroplasmosis in the semiarid region of Pernambuco, Northeastern Brazil.

Equine piroplasmosis, an economically important disease in horses, has so far not been reported in Pernambuco state, Brazil. This study aimed to evaluate the seroprevalence of anti-Babesia caballi and anti-Theileria equi antibodies based on the detection of these agents in equine blood and in ticks on horses in the municipality of Petrolina, Pernambuco, northeastern Brazil. Blood samples were drawn from 393 horses and sera were examined by ELISA. The presence of tick infestations was evaluated, and 101 ticks were subjected to DNA amplification for the detection of Babesia spp. by polymerase chain reaction (PCR). No parasites were detected in the blood smears. Anti-B. caballi and anti-T. equi antibodies were found in 27.2% (107/393) and 34.8% (137/393) horses, respectively. Infestation by Dermacentor nitens was detected in 4.3% (17/393) of the horses. There was no DNA amplification of the agents in ticks. The risk factors for the presence of anti-T. equi antibodies (P < 0.05) were: purebred (P < 0.001), animals older than 156 months (P = 0.014), and the presence of ticks (P = 0.001). No risk factors for B. caballi were identified. This study confirmed the circulation of agents of equine piroplasmosis in the municipality of Petrolina, state of Pernambuco, Brazil.