Triatomine vectors of Trypanosoma cruzi in an endemic area for Chagas disease in Northeast Brazil

ABSTRACT Background: We assessed the distribution of triatomines in an endemic area for Chagas disease. Methods: This retrospective study used secondary data extracted from the Official System of the National Chagas Disease Control Program (Sistema Oficial do Programa Nacional de Controle da Doença de Chagas - SisPCDCh). Results: A total of 7,257 (725.7 ± 221.7 per year) specimens were collected from 2013 to 2022. Most of them (6,792; 93.6%) were collected in the intradomicile and 465 (6.4%) in the peridomicile. A total of 513 (7.1%) triatomines tested positive for the presence of trypomastigote forms, similar to Trypanosoma cruzi. Conclusions: The spatial analysis revealed a heterogeneous distribution of triatomines across different municipalities.

Larvoscopic study on Dictyocaulus sp. in the faeces of beef cattle in northeastern Brazil / Estudo larvoscópico de Dictyocaulus sp. em fezes de bovinos de corte do nordeste do Brasil

Abstract The lungworm Dictyocaulus viviparus has an important role in cattle health and productivity worldwide, since infections can lead to substantial economic losses. Despite its importance, few studies investigating the epidemiological aspects of infection by this parasite have been conducted. The aim of this study was to report the occurrence of lungworm infection in beef cattle herds reared in an area of livestock production in the northeastern region of Brazil. From September 2020 to August 2021, monthly fecal samples (n = 493) were collected from 46 beef cattle. Among all the animals assessed, lungworm larvae were detected in 8.7% (4/46). None of them presented any clinical sign suggestive of infection by lungworm parasites. Twenty larvae were retrieved, with the minimum number (n = 1) detected in October and December, and the maximum number (n = 13) in November. These presented a mean length of 363 μm (± 28.65 μm) and mean width of 19 μm (± 1.03 μm), and were morphologically similar to Dictyocaulus sp.. This study reports the occurrence of this parasite in this livestock production area. Lastly, local veterinarians need to be aware of inclusion of this parasite in the differential diagnosis of other respiratory infections in beef cattle.

Resumo O parasito pulmonar Dictyocaulus viviparus tem um papel importante na saúde e produtividade bovina em todo o mundo, uma vez que infecções podem levar a perdas econômicas. Além de sua importância, poucos estudos que investigam aspectos epidemiológicos das infecções por esse parasito têm sido realizados. Objetivou-se, nesta pesquisa, relatar a ocorrência de infecção por nematódeos pulmonares em rebanhos bovinos de corte, criados em uma importante área de produção pecuária, na região Nordeste do Brasil. De setembro de 2020 a agosto de 2021, foram coletadas, mensalmente, amostras fecais (n = 493) de 46 bovinos de corte. De todos os animais avaliados, larvas de nematódeos pulmonares foram detectadas em 8,7% (4/46). Os animais não apresentaram nenhum sinal clínico sugestivo de infecção por parasitos pulmonares. Vinte larvas foram recuperadas, com o número mínimo (n = 1) detectado em outubro e dezembro, e o número máximo (n = 13) em novembro. Apresentavam comprimento médio de 363 μm (± 28,65 μm), largura média de 19 μm (±1,03 μm) e eram morfologicamente semelhantes a Dictyocaulus sp.. Este estudo relata a ocorrência desse parasito nesta área. Logo, os veterinários locais devem estar atentos à inclusão desse parasito no diagnóstico diferencial de outras infecções respiratórias em bovinos de corte.

Larvicidal activity of Caesalpinia ferrea Mart. and Lippia origanoides Cham. Against Aedes aegypti (LINNAEUS, 1762) (Diptera: Culicidae)

The control of Aedes aegypti has been considered one of the most important public health challenges worldwide. Chemical compounds have long been used for this purpose, but resistance to these molecules has also increased. Therefore, over the last few years several studies have focused on the development of alternative tools, particularly those based on plant metabolites. The purpose of this study was to assess the larvicidal activity of Caesalpinia ferrea and Lippia origanoides against Ae. aegypti. Larvae (L3) of Ae. aegypti Liverpool and Rockefeller strains, as well as of the Recife population were exposed to different concentrations of C. ferrea (ranging from 13.1 to 105 mg/mL) and L. origanoides (ranging from 16.3 to 130 mg/mL), and the mortality rate was evaluated up to 48 hours after the beginning of the experiment. All tested groups and ontrol group were quadruplicated. For C. ferrea, mortality ranged from 42.5% to 100% for Ae. aegypti Liverpool strain, from 67% to 100% for Ae. aegypti Rockfeller strain, and 57% to 100% for Ae. aegypti Recife population after 48 hours of larval exposure. For L. origanoides, the larvicidal activity ranged from 75% to 100% for Ae. aegypti Liverpool strain, from 61.5% to 100% for Ae. aegypti Rockfeller strain, and from 60.5% to 100% for Ae. aegypti Recife population. The hydro ethanol extract of C. ferrea and L. origanoides presented larvicidal activity against Ae. aegypti.

Sandflies in an endemic area for Visceral Leishmaniasis in Northeastern Brazil / Flebotomíneos em uma área endêmica para Leishmaniose Visceral no Nordeste do Brasil

Abstract Phlebotomines of the genus Lutzomyia are important vector for species of Leishmania, the etiological agent of leishmaniasis. The aim of this study was to assess the diversity of sandflies in an endemic area for Visceral Leishmaniasis (VL). Sampling was performed in four localities on the coast of the municipality of Goiana, state of Pernambuco, Northeastern Brazil. Specimens were collected monthly on three consecutive nights, from November 2017 to October 2018. CDC light traps were installed at a height of 1.5 m above the ground, in two ecotypes (i.e. tree and animal facility), both in peridomestic areas. A total of 5,205 sandflies were collected, among which the species Lutzomyia longipalpis (99.85%; 5,197/5,205) was the most common, followed by Lutzomyia evandroi (0.13%; 07/5,205) and Lutzomyia whitmani (0.02%; 01/5,205). Specimens of L. longipalpis were collected throughout the study period and most of them were found near to the animal facilities. The findings from this research indicate that vectors for Leishmania infantum are present in the study area throughout the year, along with occurrences of vectors relating to Cutaneous Leishmaniasis (CL). Preventive vector control measures need to be implemented in Goiana to reduce the risk of infection for the human and animal populations.

Resumo Flebotomíneos do gênero Lutzomyia são importantes vetores de espécies de Leishmania, agente etiológico das leishmanioses. O objetivo deste estudo foi avaliar a diversidade de flebotomíneos em área endêmica para Leishmaniose Visceral (LV). As coletas foram realizadas em quatro localidades do litoral do município de Goiana, Pernambuco, Nordeste do Brasil. Os espécimes foram coletados mensalmente em três noites consecutivas de novembro de 2017 a outubro de 2018. Foram instaladas armadilhas luminosas modelo CDC a uma altura de 1,5 m acima do solo em dois ecótopos (ex. árvore e instalações de animais), ambos em áreas peridomiciliares. Um total de 5.205 flebotomíneos foi coletado, sendo Lutzomyia longipalpis (99,85%; 5.197/5.205) a mais comum, seguida por Lutzomyia evandroi (0,13%; 07/5.205) e Lutzomyia whitmani (0,02%; 01/5.205). L. longipalpis foi coletada durante todo o período do estudo. A maioria dos espécimes foi detectada perto das instalações dos animais. Os achados deste estudo indicam a presença de vetores de Leishmania infantum na área avaliada ao longo do ano, bem como a ocorrência de vetores relacionados à Leishmaniose Cutânea (LC). Medidas preventivas de controle vetorial devem ser implementadas em Goiana para reduzir o risco de infecção à população humana e animal.

Spatial distribution of triatomine bugs in a Chagas disease endemic region in Brazil

Abstract INTRODUCTION: Trypanosoma cruzi is the etiological agent of Chagas disease (CD), a zoonotic infection transmitted by triatomine bug vectors to human beings. Although the story of this parasitic infection was born in Brazil and here this has made major step forward information, the same cannot be said about the actual distribution of the triatomine vector in several areas of this country. The aim of this study was to assess the occurrence of triatomine species in an endemic region for CD in Northeastern Brazil. METHODS: A retrospective study was performed using data obtained from 2008 to 2017. All information was provided by the V Gerência Regional de Saúde of the state of Pernambuco. The spatial distribution of triatomine species was analyzed by drawing a map using the Quantum geographic information system. RESULTS: A total of 4,694 triatomine specimens (469.4 ± 221.2 per year) were collected during the period 2008-2017, with 94.5% (4,434/4,694) at the intradomicile and 5.5% (260/4,694) at peridomicile environment. Of all arthropods collected, 92.5% (4,340/4,694) and 7.5% (354/4,694) were adults and nymphs, respectively. The species most frequently detected were Panstrongylus lutzi (30.36%), Triatoma brasiliensis (26.12%), Triatoma pseudomaculata (22.43%), and Panstrongylus megistus (20.54%). CONCLUSIONS: These data contribute to a better understanding of the distribution of T. cruzi infection in the Northeastern region of Brazil. Preventive measures based on vector control should be implemented in the study area in order to reduce the burden this neglected tropical disease.

Spatial distribution of Aedes aegypti (Diptera: Culicidae) in vulnerable areas for the transmission of arboviruses

Abstract INTRODUCTION: Areas at risk of transmission of arboviruses have been monitored using ovitraps. This study aimed to evaluate the spatial distribution of Aedes aegypti in vulnerable areas for the transmission of arboviruses and assess the influence of climatic conditions on the infestation of these culicids. METHODS: Ovitraps were installed in Agrestina, Pernambuco, Northeastern Brazil. RESULTS: Overall, 44,936 eggs were collected, and the indexes of infestation varied. Relative humidity was significantly associated with the infestations. CONCLUSIONS: Using ovitraps, entomologic indexes and analysis of climatic factors might be good strategies for monitoring vulnerable areas for the transmission of arboviruses.

Seroprevalence of neospora caninum and toxoplasma gondii in dogs from an urban area of North-eastern Brazil: a spatial approach

Abstract INTRODUCTION: The present study aimed to assess the seroprevalence and spatial distribution of Neospora caninum and Toxoplasma gondii in dogs. METHODS: Blood samples (n = 241) were collected and analyzed for the presence of anti-N. caninum and anti-T. gondii antibodies. The spatial distribution was evaluated using kernel density estimation (KDE). RESULTS Anti-N. caninum and anti-T. gondii antibodies were detected in 24.06% (58/241) and 9.54% (23/241) of samples, respectively. A heterogeneous spatial distribution of positive dogs was observed across the city. CONCLUSIONS These data are pivotal for better understanding the dynamics of infection caused by these protozoa in the canine population.

Seroprevalence and spatial distribution of canine leishmaniasis in an endemic region in Brazil: how has the situation changed after 10 years?

Abstract INTRODUCTION: Herein, we assessed the seroprevalence and spatial distribution of Leishmania infantum in dogs in Garanhuns, Northeastern Brazil. METHODS: Sera samples (n = 242) were analyzed using an enzyme-linked immunosorbent assay (ELISA). The spatial distribution of dogs seropositive for anti-Leishmania infantum antibodies was evaluated using kernel density estimation. RESULTS: A total of 2.4% (6/242) of the animals were seropositive for anti-Leishmania infantum antibodies. The kernel map showed their distribution to be heterogeneous over the city, with a hotspot in the northeastern region. CONCLUSIONS: The reported data illustrate the circulation of parasites of the genus Leishmania in a canine population.

Reliability of different methods of diagnosing intestinal parasites in horses

Parasitism by intestinal nematodes may cause serious injuries to equines affecting their performance, given that the parasites compete for food and cause irritation, internal bleeding and anaemia. The diagnostic methods currently available are not efficient in detecting all the species of parasites simultaneously, hampering reliable diagnosis. Therefore, the purpose of this study was to evaluate four diagnostic methods for detecting equine intestinal parasites in the southern hinterland of Pernambuco, Brazil. Fecal samples (n = 87) were collected and examined through flotation based methods (Willis-Mollay, modified centrifugal flotation and EPG/OPG) and sedimentation (Hoffman). Of the total number of samples examined, 77.0% (67/87) were positive by modified centrifugal flotation; 44.8% (39/87) were positive by the Willis-Mollay method; 34.5% (30/87) by the Hoffman method and 28.7% (25/87) by the EPG/ OPG method. The Kappa index indicated moderate concordance between the Willis-Mollay and modified centrifugal flotation techniques (K= 0.477); Willis-Mollay and EPG/OPG (K= 0.466); EPG/OPG and Hoffman (K= 0.425). In conclusion, modified centrifugal flotation presented high sensitivity for detection of parasites of the Strongylida order and Parascaris spp. It may, therefore, be used in association with the Willis-Mollay technique as a safe and accurate method of diagnosis.

Detection and molecular characterization of Trypanosoma (Duttonella) vivax in dairy cattle in the state of Sergipe, northeastern Brazil / Detecção e caracterização molecular de Trypanosoma (Duttonella) vivax em gado leiteiro no estado de Sergipe, no Nordeste do Brasil

Abstract Trypanosoma (Duttonella) vivax is an important cause of economic losses among feedlot cattle. These losses are related to the morbidity, mortality, reproductive issues and decreased production. It is known that the clinical signs observed in infections by this protozoon are similar to other hemoparasitosis, which difficult the diagnosis. Therefore, the aim of this study was to detect and molecularly characterize an outbreak of trypanosomiasis caused by T. (D.) vivax in dairy cattle in the municipality of São Miguel Aleixo, state of Sergipe, Brazil. Blood samples from cattle (n = 15) presenting clinical signs compatible with trypanosomiasis were collected and parasitological and molecular evaluated. Among the samples analyzed, 34% (5/15) were positive from blood smears, 60% (9/15) from the buffy coat method and 80% (12/15) from the molecular method. The DNA sequence obtained (659 bp) showed 99% similarity to T. (D.) vivax sequences that are available in the GenBank database. The presence of this protozoon in cattle herds is a problem for producers. Diagnosing trypanosomiasis is problematic because its evolution is similar to that of other parasitic blood diseases. In addition, this is the first report of infection by T. (D.) vivax in cattle in the state of Sergipe, northeastern Brazil.

Resumo Trypanosoma (Duttonella) vivax é responsável por consideráveis perdas econômicas na bovinocultura. Estas perdas estão relacionados à morbidade, mortalidade, problemas reprodutivos e declínio na produção. Sabe-se que os sinais clínicos apresentados em infecções por este protozoário se assemelha a outras hemoparasitoses, dificultando muitas vezes o diagnóstico. Portanto, objetivou-se com este estudo detectar a ocorrência de T. (D.) vivax em bovinos leiteiros no município de São Miguel Aleixo, Estado de Sergipe, Brasil. Para tanto, amostras de sangue (n = 15) foram coletadas e avaliadas através de métodos parasitológicos e moleculares. Do total das amostras analisadas, 34% (5/15) foram positivas no esfregaço sanguíneo, 60% (9/15) pelo método do Buffy Coat, enquanto na biologia molecular 80% (12/15) amplificaram um fragmento de DNA (659 pb) compatível com T. (D.) vivax (GenBank). Em conclusão a presença de T. (D.) vivax nos rebanhos bovinos caracteriza-se como um problema para os pecuaristas, como também para o diagnóstico, uma vez que essa tripanossomíase apresenta evolução semelhante a outras hemoparasitoses. Ademais, este é o primeiro relato de infecção por T. (D.) vivax em bovinos do estado de Sergipe, nordeste do Brasil.

Phlebotomines in an area endemic for American cutaneous leishmaniasis in northeastern coast of Brazil / Flebotomíneos em uma área endêmica para Leishmaniose Tegumentar Americana no litoral do Nordeste do Brasil

Abstract Phlebotomines have worldwide distribution with many species present in Brazil, including the northeastern region, where the fauna is very diverse. The aim of this study was to identify the sandfly fauna in an area endemic for American cutaneous leishmaniasis (ACL) in the state of Pernambuco. Sandflies were caught on three consecutive nights every month from October 2015 to September 2016, from 5 pm to 5 am, using seven light traps of Centers for Disease Control (CDC) type. Females were identified and used for molecular Leishmania detection. A total of 2,174 specimens belonging to ten species were collected: Lutzomyia choti (88.2%; 1,917/2,174) was the most abundant species, followed by Lutzomyia whitmani (8.1%; 176/2,174) and Lutzomyia sordellii (1.5%; 33/2,174). The majority of the specimens were collected in peridomestic areas (64.1%; 1,394/2,174) and during the rainy period. All the samples examined were negative for Leishmania spp. The presence of Lutzomyia whitmani indoors and in peridomestic areas indicates that the inhabitants of this area are exposed to the risk of infection by the parasites responsible for ACL.

Resumo Os flebotomíneos apresentam uma ampla distribuição mundial com muitas espécies presentes no Brasil, inclusive na região Nordeste, onde a fauna é bastante rica. O objetivo desse estudo foi identificar a fauna de flebotomíneos em uma área endêmica para Leishmaniose Tegumentar Americana (LTA), no estado de Pernambuco. As capturas foram realizadas mensalmente, durante três noites consecutivas das 17h às 5h, utilizando sete armadilhas luminosas tipo CDC, no período de outubro de 2015 a setembro de 2016. As fêmeas identificadas foram utilizadas para análise molecular para detecção de Leishmania. Um total de 2.174 espécimes pertencentes a dez espécies foram coletadas: Lutzomyia choti (88,2%; 1.917/2.174) a espécie mais abundante, seguida por Lutzomyia whitmani (8,1%; 176/2.174) e Lutzomyia sordellii (1,5%; 33/2.174). A maioria dos espécimes foi coletada no peridomicílio (64,1%; 1.394/2.174) e no período chuvoso. Todas as amostras avaliadas foram negativas para Leishmania spp. A presença de Lutzomyia whitmani no intradomicílio e peridomicílio indica que a população residente nesta área está exposta ao risco de infecção por parasitos causadores de LTA.

Sandflies (diptera: psychodidae) in an urban area of Northeastern Brazil

Abstract INTRODUCTION: The sandfly fauna is well studied globally. In Brazil, sandfly fauna is very diverse in the Northeast region, especially in states such as Maranhão, Ceará, and Bahia. However, in the State of Pernambuco, the distribution of these insects is still not well known. Therefore, the objective of this study was to identify the different species that constitute the sandfly fauna in an urban area in the Northeast region of Brazil, where an outbreak of visceral leishmaniasis (VL) was recently reported. METHODS: The sandflies were collected from an urban area endemic for VL, at five collection points. The collection of samples was carried out from November 2014 to December 2015, using CDC light traps installed in intradomiciliary and peridomiciliary fashion. RESULTS: The collected sandflies (n = 297) belonged to eight species: Lutzomyia lenti, Lutzomyia longipalpis, Lutzomyia sallesi, Lutzomyia migonei, Lutzomyia walkeri, Lutzomyia capixaba, Lutzomyia carmelinoi, and Lutzomyia whitmani. Most of the specimens collected were peridomiciliary (247/297, 83%). L. lenti (154/297, 52%) was the most frequently sampled species, followed by L. longipalpis (88/297, 29.6%), and L. sallesi (42/297, 14.1%), which together accounted for over 90% of the collected sandfly specimens. CONCLUSIONS: The continued presence of L. longipalpis in urban areas, including that in intradomiciliary areas, with a predominance of females, is crucial because of the high possibility of them causing VL outbreaks, since this species is the main vector of Leishmania infantum in Brazil.

Prevalence of zoonotic visceral leishmaniasis in dogs in an endemic area of Brazil

The northeast region of Brazil is endemic for zoonotic visceral leishmaniasis (ZVL). The aim of this study was to determine the prevalence of infection in dogs in Petrolina.

Evaluation of the efficacy of cypermethrin and amitraz against Rhipicephalus (Boophilus) microplus, in the State of Pernambuco, Brazil / Avaliação da eficácia de cipermetrina e amitraz contra Rhipicephalus (Boophilus) microplus no estado de Pernambuco, Brasil

The Rhipicephalus (Boophilus ) microplus is an important tick species which affect bovines in tropical areas. Its control is based on the use of chemical acaricides, but the frequent use of these substances has been conducted to the development of tick resistance. The aim of this study was to assess the efficacy of cypermethrin and amitraz against R. (B. ) microplus collected of bovines from different municipalities of the state of Pernambuco. From August 2009 to July 2011, engorged females were collected and subjected to the "Adult Immersion Test" in order to evaluate the efficacy of cypermethrin and amitraz. The results indicate that populations of R. (B. ) microplus from Pernambuco present resistance to acaricides (i.e., cypermethrin and amitraz). In this study, a single population (Brejo da Madre de Deus) was susceptible to cypermethrin, whereas two (Timbaúba and Limoeiro) were susceptible to amitraz. Data herein reported follow a pattern observed in other regions of Brazil and alert to the fact that alternative measures of control should be implemented in this area studied.(AU)

Rhipicephalus (Boophilus ) microplus é uma importante espécie que acomete bovinos em áreas tropicais. O controle desse carrapato se baseia no uso de acaricidas químicos, mas a utilização frequente dessas substâncias tem conduzido ao desenvolvimento de resistência. O objetivo deste estudo foi avaliar a eficácia da cipermetrina e do amitraz contra R. (B. ) microplus coletadas de bovinos de diferentes municípios do estado de Pernambuco. De agosto de 2009 a julho de 2011, as fêmeas ingurgitadas foram coletadas e submetidas ao Adult Immersion Test , a fim de avaliar a eficácia de cipermetrina e amitraz. Os resultados indicam que as populações de R. (B. ) microplus de Pernambuco apresentaram resistência aos acaricidas (cipermetrina e amitraz). Neste estudo, uma única população (Brejo da Madre de Deus) foi suscetível à cipermetrina, enquanto duas (Timbaúba e Limoeiro) foram sensíveis ao amitraz. Os dados aqui relatados seguem um padrão observado em outras regiões do Brasil e alertam para o fato de que as medidas alternativas de controle devem ser implementadas na área estudada.(AU)

Occurrence of immature forms of culicids (Insecta: Diptera) in the northeastern region of Brazil / Ocorrência de formas imaturas de culicídeos (Insecta: Diptera) na região nordeste do Brasil

The Culicidae family is represented by approximately 3,610 species, among which many are involved in transmission of pathogens and parasites, thus presenting great medical-veterinary importance. In Brazil, the state of Pernambuco is considered an endemic area for many diseases vectored by mosquitoes, such as human and canine filariasis, caused by Wuchereria bancrofti and Dirofilaria immitis, respectively. The aim of this study was to evaluate the occurrence of immature forms of culicids, over an one-year period, in a specific area of northeastern region of Brazil. Culicids larvae were collected from traps located on the ground and in treetops, between october 2012 and september 2013. Ten different species of culicids were identified. The greatest number of larvae were collected in september 2013 and the lowest number in december 2012. Stegomyia (Stegomyia) albopicta (46.45%; 5,908/12,718), Culex (Culex) maxi (35.56%; 4,523/12,718) and Limatus durhamii (12.58%; 1,600/12,718) were the most frequent species. The human and animal populations living in the study area are exposed to culicids and transmission agents throughout the year, especially after the rains. Therefore, control and prevention measures against culicids must be adopted in the study area.

A família Culicidae é representada por aproximadamente 3.610 espécies, dentre as quais muitas estão envolvidas na transmissão de patógenos e parasitos, apresentando assim grande importância médico-veterinária. No Brasil, o Estado de Pernambuco é considerado área endêmica para diversas doenças transmitidas por mosquitos como, por exemplo, as filarioses humana e canina causadas pela Wuchereria bancrofti e Dirofilaria immitis, respectivamente. O objetivo deste estudo foi avaliar a ocorrência de formas imaturas de culicídeos durante um ano em uma área do Nordeste do Brasil. Larvas de culicídeos foram coletadas em armadilhas localizadas no solo e copa de árvores, no período de outubro de 2012 a setembro de 2013. Dez diferentes espécies de culicídeos foram identificadas, sendo o maior número de larvas coletadas em setembro de 2013 e o menor número em dezembro de 2012. Stegomyia (Stegomyia) albopicta (46,45%; 5.908/12.718), Culex (Culex) maxi (35,56%; 4.523/12.718) e Limatus durhamii (12,58%; 1.600/12.718) foram as espécies mais frequentes. A população humana e animal residente na área de estudo é exposta aos culicídeos e aos agentes por eles veiculados durante todo o ano, sobretudo após o período de chuvas. Portanto, medidas de controle e prevenção dos culicídeos devem ser adotadas na área estudada.

Detection of antibodies against Leishmania infantum in cats (Felis catus) from the State of Pernambuco, Brazil

Introduction: Little information is available concerning infection by Leishmania infantum in cats. Therefore, the aim of this study was to perform a serological study in domestic cats. Methods: Serum samples (n=153) obtained from animals living in the Cities of Recife and Petrolina, State of Pernambuco, Brazil, were tested by ELISA/S7® (Biogene). Results: Anti-L. infantum antibodies were detected in 3.9% (6/153) of the cats. All seroreagent animals were from Petrolina. Conclusions: These results serve as an important alert, and future studies are needed to better understand the possible role of cats in the epidemiology of visceral leishmaniasis (VL) in this area. .

Quantification of Leishmania infantum DNA in the bone marrow, lymph node and spleen of dogs / Quantificação de DNA de Leishmania infantum em medula óssea, linfonodo e baço de cães

The aim of the present study was to quantify the parasite load of Leishmania infantum in dogs using real-time PCR (qPCR). Bone marrow, lymph node and spleen samples were taken from 24 dogs serologically positive for L. infantum that had been put down by the official epidemiological surveillance service. According to the clinical signs the dogs were classified as asymptomatic or symptomatic. After DNA extraction, the samples were subjected to qPCR to detect and quantify L. infantum DNA. Out of the 24 dogs, 12.5% (3/24) were classified as asymptomatic and 87.5% (21/24) as symptomatic. Real-time PCR detected L. infantum DNA in all the animals, in at least one biological sample. In particular, 100% of bone marrow and lymph node scored positive, whereas in spleen, the presence of DNA was detected in 95.9% (23/24). In addition, out of 24 animals, 15 were microscopically positive to amastigote forms of L. infantum in bone marrow. No statistical significant difference was found in the overall mean quantity of DNA among the different biological samples (P = 0.518). Considering each organ separately, there was 100% positivity in bone marrow and lymph nodes, while among the spleen samples, 95.9% (23/24) were positive. Regarding the different clinical groups, the overall mean parasite load varied significantly (P = 0.022). According to the results obtained, it was not possible determine which biological sample was most suitable tissue for the diagnosis, based only on the parasite load. Therefore, other characteristics such as convenience and easily of obtaining samples should be taken into consideration.

O objetivo do presente estudo foi quantificar a carga parasitária de Leishmania infantum em cães pela técnica de PCR em tempo-real (qPCR). Amostras de medula óssea, linfonodo e baço foram obtidos de 24 cães sorologicamente positivos para L. infantum que foram submetidos à eutanásia pelo serviço de vigilância oficial. Segundo os sinais clínicos, os animais foram classificados em assintomáticos ou sintomáticos. Após extração de DNA, as amostras foram submetidas à qPCR para detecção e quantificação de DNA de L. infantum. Dos 24 cães, 12,5% (3/24) foram classificados como assintomáticos e 87,5% (21/24) como sintomáticos. A PCR em tempo real detectou DNA de L. infantum em 100% dos animais, em pelo menos uma amostra biológica. Considerando cada órgão isoladamente, foi observada uma positividade de 100% em medula óssea e linfonodo, já nas amostras de baço 95,9% (23/24) foram positivas. Não foi observada diferença estatística entre a quantidade média geral de DNA entre as diferentes amostras biológicas (P = 0,518). Considerando os diferentes grupos clínicos, a carga parasitária média geral variou significantemente (P = 0,022). De acordo com os resultados obtidos não foi possível eleger a mais apropriada amostra biológica para o diagnóstico, baseado apenas na carga parasitária. Portanto, outras características como a conveniência e a facilidade de obtenção da amostra devem ser consideradas.

Histological changes and immunolabeling of Leishmania infantum in kidneys and urinary bladder of dogs / Alterações histológicas e imunomarcação de Leishmania infantum em rins e bexiga de cães

The aim of this study was to assess histological alterations and perform immunolabeling of Leishmania infantum in the kidneys and urinary bladder of naturally infected dogs. Twenty-five urinary bladder and kidney samples of serologically positive animals (ELISA S7® Biogene and IFAT ≥ 1:40 - Biomanguinhos/Fiocruz) were analyzed by means of immunohistochemical and histological techniques. Cystitis was found in 44% (11/25) of the bladder samples and membranoproliferative glomerulonephritis in 92% (23/25) of the kidney samples. Immunolabeling of the parasite revealed that 32% (8/25) of the bladders and 8% (2/25) of the kidneys were positive. In conclusion, the immunohistochemical technique is a useful tool for detecting amastigote forms of L. infantum in organs of infected dogs. In addition, this was the first report of detection of amastigote forms ofL. infantum in the bladders of dogs.

Objetivou-se neste estudo avaliar as alterações histológicas e realizar a imunomarcação de Leishmania infantum em rins e bexiga de cães naturalmente infectados. Vinte e cinco amostras de bexiga e rins de animais sorologicamente (ELISA S7® Biogene and IFAT ≥ 1:40 - Biomanguinhos/Fiocruz) positivas foram analisadas histologicamente e por meio da técnica de imuno-histoquímica. Os resultados revelaram cistite em 44% (11/25) das amostras de bexiga e glomerulonefrite membranoproliferativa em 92% (23/25) das amostras de rins. A imunomarcação do parasito revelou 32% (8/25) e 8% (2/25) de positividade em bexiga e rins, respectivamente. Conclui-se que a técnica de imunohistoquímica é uma útil ferramenta para detecção de formas amastigotas de L. infantum em órgãos de cães infectados. Além disso, o presente trabalho reporta a primeira descrição de formas amastigotas de L. infantum em bexiga de cães.

Susceptibility of Rhipicephalus (Boophilus) microplus (Acari: Ixodidae) to pyrethroids and their associations in Pernambuco, Brazil / Susceptibilidade de Rhipicephalus (Boophilus) microplus (Acari: Ixodidae) a piretróides e suas associações em Pernambuco, Brasil

The synthetic pyrethroids and their associations have been widely used for controlling Rhipicephalus (Boophilus) microplus. The frequent use of acaricides has been inducing the development of resistance in the tick populations. The aim of this study was to assess the susceptibility of R. (B.) microplus populations to pyrethroids and their associations in the region of Garanhuns, Pernambuco, Brazil. In addition, the level of information among farm owners regarding tick control measures was investigated. Ticks were collected directly from naturally infested dairy cattle in the region and were exposed to pyrethroids and their associations. At the same time, an epidemiological questionnaire was applied with the aim of investigating the level of information among the farmers. The results reported here indicate that R. (B.) microplus populations in the dairy region of Garanhuns show resistance to pyrethroids and their associations, except when the product is associated with piperonyl butoxide. Regarding the results from the epidemiological survey, it was seen that there is a considerable lack of information among the farmers in relation to ixodid control measures. The level of ticks resistance to acaricides varied widely across the region studied. No alternative control programs have been implemented among these farms, thus demonstrating that there is a need for more information relating to the biology and control of R. (B.) microplus.

Os piretróides sintéticos e associações são acaricidas amplamente utilizados para o controle do Rhipicephalus (Boophilus) microplus. O uso frequente destes fármacos tem induzido o surgimento de populações de carrapatos resistentes. Objetivou-se neste estudo avaliar a susceptibilidade de populações de R. (B.) microplus aos piretróides e associações. Além disso, investigou-se o nível de informações dos proprietários com relação ás medidas de controle utilizadas. Os carrapatos foram coletados diretamente de bovinos naturalmente infestados na região leiteira de Garanhuns, Pernambuco e expostos a piretróides e suas associações. Contemporaneamente, foi aplicado um questionário epidemiológico com o objetivo de avaliar o nível de informação dos produtores. Os resultados aqui obtidos demonstram que populações de R. (B.) microplus provenientes da região leiteira de Garanhuns apresentam resistência aos piretróides, exceto quando o produto está associado com butóxido de piperonila. Em se tratando dos resultados referentes ao inquérito epidemiológico, verificou-se considerável falta de informação por parte dos produtores com relação ás medidas de controle de ixodídeos. Assim, verifica-se que o nível de resistência aos acaricidas é muito variável na região estudada e que não há, nas propriedades, a adoção de programas alternativos de controle, demonstrando a necessidade de maiores informações relacionadas á biologia e ao controle do R. (B.) microplus.

Vector competence of Culex quinquefasciatus Say, 1823 exposed to different densities of microfilariae of Dirofilaria immitis (Leidy, 1856) / Competência vetorial de Culex quinquefasciatus Say, 1823 exposto a diferentes densidades de microfilárias de Dirofilaria immitis (Leidy, 1856)

The metropolitan region of Recife, Brazil is endemic for Dirofilaria immitis and has an environment favorable to the development of Culex quinquefasciatus. The goal of this study was to evaluate the vector competence of the Cx. quinquefasciatus RECIFE population for D. immitis transmission. A total of 2,104 females of Cx. quinquefasciatus RECIFE population were exposed to different densities of D. immitis microfilariae blood meals, ranging from 1,820 to 2,900 mf/ml of blood, in a natural membrane apparatus. The results showed a variation between 92.3 percent and 98.8 percent of females fed. The exposure of the Cx. quinquefasciatus RECIFE population to different densities of microfilariae did not influence the mortality of the mosquitoes. Infective larvae from D. immitis were observed in the Malpighian tubules beginning on the 12th day, whereas larvae were observed in the head and proboscis beginning on the 13th day following infection. The vector efficiency index (VEI) presented by the mosquitoes ranged from 7.8 to 56.5. The data demonstrates that the Cx. quinquefasciatus RECIFE population has great potential for the transmission of D. immitis, as it allowed the development of the filarid until the infectious stage at the different densities of microfilariae to which it was exposed.

A Região Metropolitana do Recife é endêmica para Dirofilaria immitis e possui ambiente favorável para o desenvolvimento de Culex quinquefasciatus. Neste estudo avaliou-se a competência vetorial de Cx. quinquefasciatus população RECIFE para a transmissão de D. immitis. Para tanto, 2.104 fêmeas de Cx. quinquefasciatus população RECIFE foram expostas a diferentes densidades de microfilárias de D. immitis, variando de 1.820 a 2.900 mf/ml de sangue por meio de membrana natural. Os resultados obtidos demonstraram variação de 92,3 por cento a 98,8 por cento de fêmeas ingurgitadas após a alimentação. A exposição de Cx. quinquefasciatus população RECIFE a diferentes densidades de microfilárias não influenciou na mortalidade dos mosquitos. Larvas infectantes de D. immitis foram observadas nos túbulos de Malpighi a partir do 12º dia, enquanto na cabeça e na probóscide foram observadas a partir do 13º dia após a infecção. Os índices de eficiência vetorial (IEV) apresentados pelo culicídeo variaram de 7,8 a 56,5. Os dados obtidos demonstraram que Cx. quinquefasciatus população RECIFE tem grande potencial para a transmissão de D. immitis, pois permitiu o desenvolvimento do filarídeo até o estágio infectante nas diferentes densidades de microfilárias às quais foi exposto.