RESUMEN
Phlebotomine sand flies are recognized as a primary vector of Leishmania and are also suspected vectors of Trypanosoma. The transmission cycle of these parasites relies on the distribution of sand fly vectors, parasites, and reservoir animals. This study aimed to detect Leishmania and Trypanosoma DNA and identify the sources of bloodmeals in post-feeding sand flies captured across Thailand. A total of 42,911 field female sand flies were collected from 11 provinces across Thailand using CDC light traps. Among these, 253 post-feeding sand flies were selected for analysis. The predominant species in this study was Sergentomyia khawi (33.60 %). The DNA was extracted from individual female sand flies. Polymerase chain reaction (PCR), specific to the internal transcribed spacer 1 (ITS1) and the small subunit ribosomal RNA (SSU rRNA) gene regions were used to detect the presence of Leishmania and Trypanosoma DNA, respectively. Additionally, cytochrome c oxidase subunit I (COI) gene region was utilized to identify the sources of host bloodmeals. Leishmania DNA was not detected in any specimens. The analysis of SSU rRNA sequences revealed the presence of Trypanosoma DNA (11.46 %, 29/253) in sand fly samples. Among these samples, T. noyesi (1.58 %, 4/253) was identified in Idiophlebotomus longiforceps and Phlebotomus asperulus, Trypanosoma Anura01+02/Frog2 (1.18 %, 3/253) in Se. khawi, and Trypanosoma Anura04/Frog1 (8.70 %, 22/253) in Se. khawi, Se. hivernus and Grossomyia indica. Bloodmeal analysis utilizing the COI gene revealed a diverse range of vertebrate hosts' blood, including bird, bat, frog and sun skink. Our findings confirm the presence of Trypanosoma DNA and identify the sources of bloodmeals from vertebrate hosts in various sand fly species, suggesting their potential as possible vectors for Trypanosoma in Thailand. Furthermore, our study is the first to provide molecular evidence using the COI gene to identify frogs as a host blood source for sand flies in Thailand. Further studies focusing on the isolation of live parasites in sand flies to confirm vector potential and examining the role of animal reservoirs will enhance our understanding of the host-parasite relationship and enable more efficient control for disease transmission.
Asunto(s)
ADN Protozoario , Leishmania , Psychodidae , Trypanosoma , Animales , Tailandia/epidemiología , Trypanosoma/genética , Trypanosoma/aislamiento & purificación , Trypanosoma/clasificación , Femenino , Leishmania/genética , Leishmania/aislamiento & purificación , Leishmania/clasificación , ADN Protozoario/genética , Psychodidae/parasitología , Insectos Vectores/parasitología , Filogenia , Reacción en Cadena de la Polimerasa , ADN Espaciador Ribosómico/genética , Complejo IV de Transporte de Electrones/genética , Sangre/parasitologíaRESUMEN
BACKGROUND: Aedes and Anopheles mosquitoes are responsible for tremendous global health burdens from their transmission of pathogens causing malaria, lymphatic filariasis, dengue, and yellow fever. Innovative vector control strategies will help to reduce the prevalence of these diseases. Mass rearing of mosquitoes for research and support of these strategies presently depends on meals of vertebrate blood, which is subject to acquisition, handling, and storage issues. Various blood-free replacements have been formulated for these mosquitoes, but none of these replacements are in wide use, and little is known about their potential impact on competence of the mosquitoes for Plasmodium infection. METHODS: Colonies of Aedes aegypti and Anopheles stephensi were continuously maintained on a blood-free replacement (SkitoSnack; SS) or bovine blood (BB) and monitored for engorgement and hatch rates. Infections of Ae. aegypti and An. stephensi were assessed with Plasmodium gallinaceum and P. falciparum, respectively. RESULTS: Replicate colonies of mosquitoes were maintained on BB or SS for 10 generations of Ae. aegypti and more than 63 generations of An. stephensi. The odds of engorgement by SS- relative to BB-maintained mosquitoes were higher for both Ae. aegypti (OR = 2.6, 95% CI 1.3-5.2) and An. stephensi (OR 2.7, 95% CI 1.4-5.5), while lower odds of hatching were found for eggs from the SS-maintained mosquitoes of both species (Ae. aegypti OR = 0.40, 95% CI 0.26-0.62; An. stephensi OR = 0.59, 95% CI 0.36-0.96). Oocyst counts were similar for P. gallinaceum infections of Ae. aegypti mosquitoes maintained on SS or BB (mean ratio = [mean on SS]/[mean on BB] = 1.11, 95% CI 0.85-1.49). Similar oocyst counts were also observed from the P. falciparum infections of SS- or BB-maintained An. stephensi (mean ratio = 0.76, 95% CI 0.44-1.37). The average counts of sporozoites/mosquito showed no evidence of reductions in the SS-maintained relative to BB-maintained mosquitoes of both species. CONCLUSIONS: Aedes aegypti and An. stephensi can be reliably maintained on SS over multiple generations and are as competent for Plasmodium infection as mosquitoes maintained on BB. Use of SS alleviates the need to acquire and preserve blood for mosquito husbandry and may support new initiatives in fundamental and applied research, including novel manipulations of midgut microbiota and factors important to the mosquito life cycle and pathogen susceptibility.
Asunto(s)
Aedes , Anopheles , Mosquitos Vectores , Animales , Aedes/parasitología , Aedes/fisiología , Anopheles/parasitología , Anopheles/fisiología , Mosquitos Vectores/parasitología , Mosquitos Vectores/fisiología , Plasmodium gallinaceum/fisiología , Plasmodium falciparum/fisiología , Bovinos , Femenino , Sangre/parasitología , Conducta AlimentariaRESUMEN
The Australian skink Egernia stokesii had been recognised as a host of two species of Plasmodium, Plasmodium mackerrasae and P. circularis; nevertheless, molecular data are available for only a single haemosporidian species of this host. Its sequences are labelled as "Plasmodium sp." or "Plasmodium mackerrasae", but morphological characteristics of this isolate are unavailable. Phylogenetic analyses of these sequences placed them into the clade of the genus Haemocystidium. In this study, blood samples of six E. stokesii were analysed by both, molecular and microscopic methods to clarify the haemosporidia of this lizard. Application of these approaches offered discordant results. Whereas sequence analysis clustered our isolates with lizard species of Haemocystidium, morphology of blood stages is more akin to Plasmodium than Haemocystidium. However, limited sampling, indistinguishable nuclei/merozoites and risk of possible hidden presence of mixed infection prevent reliable species identification of detected parasites or their description as new species of Haemocystidium.
Asunto(s)
Haemosporida , Lagartos , Filogenia , Animales , Lagartos/parasitología , Australia , Haemosporida/genética , Haemosporida/clasificación , Haemosporida/aislamiento & purificación , ADN Protozoario/genética , Análisis de Secuencia de ADN , Datos de Secuencia Molecular , Análisis por Conglomerados , ADN Ribosómico/genética , Microscopía , Sangre/parasitología , ARN Ribosómico 18S/genética , Infecciones Protozoarias en Animales/parasitologíaRESUMEN
BACKGROUND: Control of malaria parasite transmission can be enhanced by understanding which human demographic groups serve as the infectious reservoirs. Because vector biting can be heterogeneous, some infected individuals may contribute more to human-to-mosquito transmission than others. Infection prevalence peaks in school-age children, but it is not known how often they are fed upon. Genotypic profiling of human blood permits identification of individual humans who were bitten. The present investigation used this method to estimate which human demographic groups were most responsible for transmitting malaria parasites to Anopheles mosquitoes. It was hypothesized that school-age children contribute more than other demographic groups to human-to-mosquito malaria transmission. METHODS: In a region of moderate-to-high malaria incidence in southeastern Malawi, randomly selected households were surveyed to collect human demographic information and blood samples. Blood-fed, female Anopheles mosquitoes were sampled indoors from the same houses. Genomic DNA from human blood samples and mosquito blood meals of human origin was genotyped using 24 microsatellite loci. The resultant genotypes were matched to identify which individual humans were sources of blood meals. In addition, Plasmodium falciparum DNA in mosquito abdomens was detected with polymerase chain reaction. The combined results were used to identify which humans were most frequently bitten, and the P. falciparum infection prevalence in mosquitoes that resulted from these blood meals. RESULTS: Anopheles females selected human hosts non-randomly and fed on more than one human in 9% of the blood meals. Few humans contributed most of the blood meals to the Anopheles vector population. Children ≤ 5 years old were under-represented in mosquito blood meals while older males (31-75 years old) were over-represented. However, the largest number of malaria-infected blood meals was from school age children (6-15 years old). CONCLUSIONS: The results support the hypothesis that humans aged 6-15 years are the most important demographic group contributing to the transmission of P. falciparum to the Anopheles mosquito vectors. This conclusion suggests that malaria control and prevention programmes should enhance efforts targeting school-age children and males.
Asunto(s)
Anopheles , Sangre , Conducta de Búsqueda de Hospedador , Malaria Falciparum , Adolescente , Adulto , Anciano , Animales , Niño , Preescolar , Femenino , Humanos , Masculino , Persona de Mediana Edad , Anopheles/parasitología , ADN/sangre , Genotipo , Malaria/sangre , Malaria/parasitología , Malaria/prevención & control , Malaria/transmisión , Malaria Falciparum/sangre , Malaria Falciparum/parasitología , Malaria Falciparum/prevención & control , Malaria Falciparum/transmisión , Comidas , Mosquitos Vectores/parasitología , Plasmodium falciparum/genética , Sangre/parasitología , MalauiRESUMEN
O presente estudo teve como objetivo detectar por meio da Reação em cadeia da Polimerase (PCR) a frequência de Ehrlichiacanis, Babesia spp. e Anaplasma platys em cães, relacionando a prevalência dos achados hematológicos aos resultados positivos pela PCR. Foram avaliadas 209 amostras de sangue de cães atendidos em clínica veterinária particular do município de Queimados, RJ, Brasil, no período de julho a outubro de 2014. Foram realizados hemograma completo e extração de DNA para técnica de PCR. Do total de 209 animais, 19,1% (40/209) animais apresentaram resultado positivo para hemoparasitos pela técnica de PCR. Destes, 52,5% (21/40) foram positivos para E. canis, 27,5% (11/40) positivos para Babesia spp. e 10% (4/40) positivos para A. platys. Quatro animais (1,91%), dos 209 testados, foram positivos para pelo menos dois agentes, caracterizando assim coinfecção. Dos 40 cães positivos para algum dos agentes testados, 25 (62,5%) estavam trombocitopênicos. Ou seja, 15 cães (37,5%) reagiram positivos para hemoparasitos, mas não apresentavam trombocitopenia. A anemia foi um achado comum, sobretudo nas infecções por Babesia spp., 100% (11/11) e E.canis, 90,5% (19/21). A técnica de PCR foi um importante método diferencial na detecção das principais hemoparasitoses caninas, juntamente com os achados clínicos e hematológicos para o diagnóstico preciso da infecção em questão.
The present study aimed to detect, by means of Polimerase chain reaction (PCR), the frequency of Ehrlichia canis, Babesia spp. and Anaplasma platys in dogs, relating the prevalence of hematological findings to positive PCR results. A total of 209 blood samples from dogs treated at a private veterinary clinic in the city of Queimados, RJ, Brazil, from July to October 2014 were evaluated. Complete blood count and DNA extraction were performed for the PCR technique. Of the total of 209 animals, 19.1% (40/209) animals were positive for hemoparasites by the PCR technique. Of these, 52.5% (21/40) were positive for E. canis, 27.5% (11/40) were positive for Babesia spp. and 10% (4/40) positive for A. platys. Four animals (1.91%) of the 209 tested were positive for at least two agents, thus characterizing coinfection. Of the 40 dogs positive for any of the agents tested, 25 (62.5%) were thrombocytopenic. That is, 15 dogs (37.5%) were positive for hemoparasites, but did not have thrombocytopenia. Anemia was a common finding, especially in infections by Babesia spp., 100% (11/11) and E. canis, 90.5% (19/21). The PCR technique was an important differential method in the detection of the main canine hemoparasitoses, together with the clinical and hematological findings for the accurate diagnosis of the infection in question.
Asunto(s)
Animales , Perros , Infecciones Protozoarias en Animales/diagnóstico , Babesia/parasitología , Sangre/parasitología , Recolección de Muestras de Sangre/veterinaria , Reacción en Cadena de la Polimerasa/veterinaria , Ehrlichia canis , Perros/parasitología , Carga de Parásitos/veterinaria , Anaplasma , Anemia/veterinariaRESUMEN
Animal trypanosomosis, caused by Trypanozoon trypanosomes (Trypanosoma evansi and T. equiperdum), and Trypanosoma vivax, is endemic to South American countries and has a negative impact on the livestock industry. However, the risk factors for trypanosomosis in Paraguay remain unknown. This study aimed to determine the risk factors for equine trypanosomosis in Paraguay based on a PCR-based molecular survey and individual horse sampling data. In this study, 739 blood samples were collected from horses in 16 departments of Paraguay between August 2019 and November 2020. To elucidate the risk factors for trypanosome infection, the relationship between trypanosome infection status detected by PCR and the location, sex, age, breed of horses, and season of sample collection was analyzed. There were no significant differences in trypanosome prevalence in horses between the eastern and western regions, ages, or breeds of horses in Paraguay. Sex and season were identified as risk factors for trypanosome infection in horses in Paraguay in the current study. These results suggest that the rainy-summer season, when vectors increase in number and their blood-sucking activity, could be the most important risk factor for trypanosome infection in Paraguay horses. Preventive measures and treatments should be developed to address these factors.
Asunto(s)
Enfermedades de los Caballos , Tripanosomiasis , Animales , Sangre/parasitología , Femenino , Enfermedades de los Caballos/diagnóstico , Enfermedades de los Caballos/epidemiología , Caballos , Masculino , Paraguay/epidemiología , Reacción en Cadena de la Polimerasa/veterinaria , Prevalencia , Factores de Riesgo , Trypanosoma/genética , Trypanosoma/aislamiento & purificación , Tripanosomiasis/diagnóstico , Tripanosomiasis/epidemiología , Tripanosomiasis/veterinariaRESUMEN
Objective: To investigate intestinal and blood parasites in people who have a history of traveling abroad during the Coronavirus disease-2019 pandemic and returning to Turkey. Methods: In this study, 104 patients with gastrointestinal system and/or fever complaints who had traveled abroad during the pandemic period and returned to Turkey were included. Parasitic agents were investigated by taking blood and stool samples from the patients. Additionally, urine samples were obtained from patients with hematuria or dysuria with the suspicion of schistosomiasis. A direct microscopic examination, the Crypto-Giardia immunochromatographic test, and ELISA methods were used in the examination of the stool samples. In order to detect Plasmodium species, blood samples were examined by preparing both the rapid diagnostic test and thick drop and thin smear preparations. Results: One or more parasite species were detected in 38 (38.5%) of 104 patients included in the study. While intestinal parasites were detected in 16 (32%) of 50 patients who traveled to Iran and 16 (33.3%) of 48 patients who traveled to Northern Iraq, blood parasites were not found. Schistosoma mansoni was detected in all 5 of the patients with a history of traveling to Sudan. Plasmodium falciparum was detected in 1 patient who traveled to the African continent. Conclusion: It is vital to take precautions to prevent parasitic diseases, such as malaria and schistosomiasis, during travels to African countries. During travels to neighboring countries of Turkey, such as Northern Iraq and Iran, hygiene should be paid attention to, so as to prevent contracting intestinal parasitic diseases. In addition, it was concluded that people who plan to travel abroad should have information about the endemic parasitic diseases of the country that they are going to.
Asunto(s)
COVID-19 , Parasitosis Intestinales , Parasitemia , Parásitos , Enfermedad Relacionada con los Viajes , Animales , Sangre/parasitología , COVID-19/epidemiología , Heces/parasitología , Humanos , Parasitosis Intestinales/epidemiología , Parasitosis Intestinales/parasitología , Pandemias , Parasitemia/epidemiología , Parasitemia/parasitología , Parásitos/aislamiento & purificación , Plasmodium/aislamiento & purificación , Turquía/epidemiología , Orina/parasitologíaRESUMEN
INTRODUCTION: Phlebotomine sand flies (Diptera: Psychodidae) are known as the vector of diseases such as leishmaniasis, bartonellosis and viral diseases. The aim of this study is to detect the host feeding pattern of sand flies in the endemic areas for leishmaniasis in Turkey (Antalya, Kayseri) and Northern Cyprus (TRNC) as well as the presence of Leishmania DNA in the specimens. METHODS: One-hundred seventy-six blood-fed sand fly specimens were examined for blood meal analysis. A SYBR Green-PCR assay was performed with specific forward primers for each host and a universal reverse primer. Primers of human and goat were used together in multiplex PCR while goat and cow were studied separately. ITS-1 qPCR assay was also performed on both blood-fed and non-blood-fed females to detect Leishmania parasites. RESULTS: Blood sources could be detected in 69 out of 176 blood-fed sand fly specimens. The results of blood meal analysis showed that specimens were fed mostly on cows (22.2%) followed by humans (5.7%), goats (2.8%) and dogs (0.6%). Multiple feeding patterns were also detected as human + cow (3.4%), cow + goat (2.8%) and human + goat (1.7%). Five of the blood-fed specimens were Leishmania spp. positive: P. major s.l. (n = 1), P. tobbi (n = 2) were L. tropica positive from Antalya, P. simici was positive for L. infantum from Kayseri and P. papatasi (n = 1) was positive for L. major from Cyprus. Leishmania infection rates were determined as 3.79%, 1.69% and 2.63% among the blood-fed sand fly specimens in Antalya, Kayseri and TRNC, respectively. CONCLUSION: The SYBR-Green-based multiplex PCR assay is a cost-effective and promising tool for blood meal identification of wild-caught sand flies as well as other blood-sucking arthropods. Feeding patterns of important vector species detected in the present study show the high risk in these endemic areas. As a next step, to identify the blood source in a shorter time and to make the test more sensitive, development of this assay to probe-based and multiplex PCR will be also planned.
Asunto(s)
Sangre , ADN Protozoario , Insectos Vectores , Leishmania , Leishmaniasis , Psychodidae , Animales , Sangre/parasitología , Bovinos , Chipre/epidemiología , ADN/genética , ADN/aislamiento & purificación , ADN Protozoario/genética , ADN Protozoario/aislamiento & purificación , Perros , Enfermedades Endémicas , Conducta Alimentaria , Femenino , Análisis de los Alimentos , Insectos Vectores/parasitología , Insectos Vectores/fisiología , Leishmania/genética , Leishmaniasis/diagnóstico , Leishmaniasis/epidemiología , Leishmaniasis/veterinaria , Comidas , Phlebotomus/parasitología , Phlebotomus/fisiología , Psychodidae/parasitología , Psychodidae/fisiología , Reacción en Cadena en Tiempo Real de la Polimerasa , Turquía/epidemiologíaRESUMEN
BACKGROUND: As China is moving onto schistosomiasis elimination/eradication, diagnostic methods with both high sensitivity and specificity for Schistosoma japonicum infections in humans are urgently needed. Microscopic identification of eggs in stool is proven to have poor sensitivity in low endemic regions, and antibody tests are unable to distinguish between current and previous infections. Polymerase chain reaction (PCR) technologies for the detection of parasite DNA have been theoretically assumed to show high diagnostic sensitivity and specificity. However, the reported performance of PCR for detecting S. japonicum infection varied greatly among studies. Therefore, we performed a meta-analysis to evaluate the overall diagnostic performance of variable-temperature PCR technologies, based on stool or blood, for detecting S. japonicum infections in humans from endemic areas. METHODS: We searched literatures in eight electronic databases, published up to 20 January 2021. The heterogeneity and publication bias of included studies were assessed statistically. The risk of bias and applicability of each eligible study were assessed using the Quality Assessment of Diagnostic Accuracy Studies 2 tool (QUADAS-2). The bivariate mixed-effects model was applied to obtain the summary estimates of diagnostic performance. The hierarchical summary receiver operating characteristic (HSROC) curve was applied to visually display the results. Subgroup analyses and multivariate regression were performed to explore the source of heterogeneity. This research was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines and was registered prospectively in PROSPERO (CRD42021233165). RESULTS: A total of 2791 papers were retrieved. After assessing for duplications and eligilibity a total of thirteen publications were retained for inclusion. These included eligible data from 4268 participants across sixteen studies. High heterogeneity existed among studies, but no publication bias was found. The pooled analyses of PCR data from all included studies resulted in a sensitivity of 0.91 (95% CI: 0.83 to 0.96), specificity of 0.85 (95% CI: 0.65 to 0.94), positive likelihood ratio of 5.90 (95% CI: 2.40 to 14.60), negative likelihood ratio of 0.10 (95% CI: 0.05 to 0.20) and a diagnostics odds ratio of 58 (95% CI: 19 to 179). Case-control studies showed significantly better performances for PCR diagnostics than cross-sectional studies. This was further evidenced by multivariate analyses. The four types of PCR approaches identified (conventional PCR, qPCR, Droplet digital PCR and nested PCR) differed significantly, with nested PCRs showing the best performance. CONCLUSIONS: Variable-temperature PCR has a satisfactory performance for diagnosing S. japonicum infections in humans in endemic areas. More high quality studies on S. japonicum diagnostic techniques, especially in low endemic areas and for the detection of dual-sex and single-sex infections are required. These will likely need to optimise a nested PCR alongside a highly sensitive gene target. They will contribute to successfully monitoring endemic areas as they move towards the WHO 2030 targets, as well as ultimately helping areas to achieve these goals.
Asunto(s)
Reacción en Cadena de la Polimerasa/métodos , Schistosoma japonicum/genética , Esquistosomiasis Japónica/diagnóstico , Animales , Sangre/parasitología , Heces/parasitología , Esquistosomiasis Japónica/parasitología , Sensibilidad y Especificidad , TemperaturaRESUMEN
Hemoparasitoses vêm se tornando cada vez mais importantes na clínica médica de pequenos animais. Dentre os agentes causadores encontramos Ehrlichiacanis, Anaplasmaplatys., e Mycoplasma spp., torna-se de grande importância conhecer a epidemiologia nos gatos domésticos. Objetivou-se com esta pesquisa fazer um levantamento retrospectivo de fichas de gatos advindos de consultas no Hospital Veterinário Mário Dias Teixeira (HOVET) que realizaram exame de Reação de Cadeia da polimerase (PCR) no laboratório de biologia molecular, na Universidade Federal Rural da Amazônia, no ano de 2018 e 2019. No total foram 72 amostras de gatos domésticos processadas, sendo 33 machos e 39 fêmeas, 70 animais SRD e 2 Siameses, todos com trombocitopenia, além de outros sinais clínicos que os levaram a precisar de atendimento veterinário, foram categorizados os meses de entrada e processamento das amostras, bairros dos animais e grupos etários. De todos os animais testados, 34,7% obtiveram diagnóstico positivo para uma das enfermidades, sendo o gênero Mycoplasma spp. o que mais prevaleceu em amostras positivas, com maior frequência em fêmeas adultas, bem como foi descrita ocorrência de E. canis apenas nesse sexo, já A. platysfoi descrito com maior frequência em machos, além de achados de infecções concomitantes observado entre os agentes Anaplasmae Mycoplasma. Concluímos que os gatos atendidos no HOVET possuíam parasitismo por diferentes agentes infecciosos.
Hemoparasitosis have become increasingly important in the small animals' internal medicine. Among the causal agents, there are Ehrlichiacanis, Anaplasmaplatys. and Mycoplasma spp., which give the understanding of the epidemiology in domestic cats a great significance. This research aimed to make a retrospective survey of records from cats that came from appointments at the Veterinary Hospital Mário Dias Teixeira (HOVET) and underwent the Polymerase Chain Reaction (PCR) test at the molecular biology laboratory, at the Amazônia Federal Rural University (UFRA), in the years of 2018 and 2019. In total, 72 samples of domestic cats were processed, from which 33 were males and 39 females, 70 of them were mongrel cats and 2 siamese, all of them showed thrombocytopenia amongst other clinical signs that led them to need a veterinary appointment, the months of admission, processing of the samples, districts the animals came from and age group were categorized. 34,7% of all the animals tested showed positive results for one of the diseases, with the genus Mycoplasma spp. being the most prevalent in positive samples, showing a higher rate in adult females, as the occurrence of E. canis was reported only in females, while A. platys was reported with a higher rate in males, as well as concomitant infections following the observation of the agents Anaplasma and Mycoplasma. In conclusion, the cats admitted at HOVET showed parasitism by different infectious agents.
Asunto(s)
Animales , Gatos , Enfermedades Parasitarias/sangre , Sangre/parasitología , Estudios Epidemiológicos , Gatos/parasitología , Reacción en Cadena de la Polimerasa/veterinaria , Ehrlichia canis , Carga de Parásitos/veterinaria , Anaplasma , Infecciones por Mycoplasma/veterinariaRESUMEN
Trypanosoma theileri is considered a non- or low-pathogenic trypanosome that generally causes latent infection in apparently healthy cattle; however, T. theileri propagates in the bloodstream and may cause clinical disease in pregnant animals or co-infection with bovine leukemia virus or Theileria orientalis. In the current study, a monthly survey of T. theileri infection over one year was carried out in a research dairy farm in Hokkaido, Japan to determine the 1) seasonal variations in the prevalence, 2) genetic characterization of T. theileri, and 3) associations of milk and blood parameters in dairy cattle with T. theileri infection, including data of metabolic profile tests and dairy herd performance tests, using linear mixed models. We found that 1) the prevalence of T. theileri infection was significantly higher in summer and winter than in other seasons; 2) T. theileri possibly showed genetic diversity in Eastern Hokkaido; and 3) T. theileri infection was associated with significantly lower levels of blood urea nitrogen, milk protein, and solids-not-fat, which are caused by a low rumen fermentation level. This is the first study to report the negative impact of T. theileri infection in dairy cattle, and our study indicates that control of T. theileri infection can improve the productivity of dairy cattle.
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Enfermedades de los Bovinos/epidemiología , Industria Lechera/economía , Variación Genética , Trypanosoma/fisiología , Tripanosomiasis/veterinaria , Animales , Sangre/parasitología , Bovinos , Enfermedades de los Bovinos/parasitología , Japón/epidemiología , Leche/parasitología , Estaciones del Año , Trypanosoma/genética , Tripanosomiasis/epidemiología , Tripanosomiasis/parasitologíaRESUMEN
Individuals with asymptomatic infection due to Plasmodium vivax are posited to be important reservoirs of malaria transmission in endemic regions. Here we studied a cohort of P. vivax malaria patients in a suburban area in the Brazilian Amazon. Overall 1,120 individuals were screened for P. vivax infection and 108 (9.6%) had parasitemia detected by qPCR but not by microscopy. Asymptomatic individuals had higher levels of antibodies against P. vivax and similar hematological and biochemical parameters compared to uninfected controls. Blood from asymptomatic individuals with very low parasitemia transmitted P. vivax to the main local vector, Nyssorhynchus darlingi. Lower mosquito infectivity rates were observed when blood from asymptomatic individuals was used in the membrane feeding assay. While blood from symptomatic patients infected 43.4% (199/458) of the mosquitoes, blood from asymptomatic infected 2.5% (43/1,719). However, several asymptomatic individuals maintained parasitemia for several weeks indicating their potential role as an infectious reservoir. These results suggest that asymptomatic individuals are an important source of malaria parasites and Science and Technology for Vaccines granted by Conselho Nacional de may contribute to the transmission of P. vivax in low-endemicity areas of malaria.
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Anopheles/parasitología , Malaria Vivax/transmisión , Plasmodium vivax/fisiología , Animales , Anopheles/fisiología , Infecciones Asintomáticas/epidemiología , Sangre/parasitología , Brasil/epidemiología , Estudios de Cohortes , Estudios Transversales , Femenino , Humanos , Malaria Vivax/epidemiología , Malaria Vivax/parasitología , Masculino , Persona de Mediana Edad , Plasmodium vivax/genética , Estaciones del AñoRESUMEN
Ticks are obligate hematophagous arthropods. Blood feeding ensures that ticks obtain nutrients essential for their survival, development, and reproduction while providing routes for pathogen transmission. However, the effectors that determine tick feeding activities remain poorly understood. Here, we demonstrate that reduced abundance of the symbiont Coxiella (CHI) in Haemaphysalis longicornis decreases blood intake. Providing tetracycline-treated ticks with the CHI-derived tryptophan precursor chorismate, tryptophan, or 5-hydroxytryptamine (5-HT; serotonin) restores the feeding defect. Mechanistically, CHI-derived chorismate increases tick 5-HT biosynthesis by stimulating the expression of aromatic amino acid decarboxylase (AAAD), which catalyzes the decarboxylation of 5-hydroxytryptophan (5-HTP) to 5-HT. The increased level of 5-HT in the synganglion and midgut promotes tick feeding. Inhibition of CHI chorismate biosynthesis by treating the colonized tick with the herbicide glyphosate suppresses blood-feeding behavior. Taken together, our results demonstrate an important function of the endosymbiont Coxiella in the regulation of tick 5-HT biosynthesis and feeding.
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Coxiella/fisiología , Serotonina/biosíntesis , Simbiosis , Garrapatas/microbiología , Garrapatas/fisiología , Animales , Sangre/parasitología , Conducta Alimentaria , Humanos , Triptófano/metabolismoRESUMEN
Sri Lanka achieved elimination status for lymphatic filariasis in 2016; still, the disease remains a potential public health issue. The present study is aimed at identifying a subperiodic Brugia sp. parasite which has reemerged in Sri Lanka after four decades via molecular-based analysis. Polymerase chain reaction performed with pan-filarial primers specific for the internal transcribed spacer region-2 (ITS-2) of the rDNA of Brugia filarial parasites isolated from human, canine, and feline blood samples yielded a 615 bp band establishing the species identity as Brugia malayi. Comparison of the ITS2 sequences of the reemerged B. malayi isolates with GenBank sequences revealed a higher sequence homology with B. pahangi than B. malayi with similar phylogenetic evidence. However, the mean interspecies Kimura-2-parameter pairwise divergence between the generated Brugia sequences with B. malayi and B. pahangi was less than 3%. During the analysis of parsimony sites of the new ITS2 sequences, substitutions at A36T, A296G, T373A, and G482A made the sequences different from both B. pahangi and B. malayi suggesting the possibility of a new genetic variant or a hybrid strain of B. malayi and B. pahangi. Mosquito dissections and xenomonitoring identified M. uniformis and M. annulifera as vectors of this novel strain of B. malayi circulating among cats, dogs, and humans in Sri Lanka.
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Brugia Malayi/clasificación , ADN Espaciador Ribosómico/genética , Filariasis Linfática/parasitología , Análisis de Secuencia de ADN/métodos , Animales , Sangre/parasitología , Brugia Malayi/genética , Brugia Malayi/aislamiento & purificación , Gatos , Culicidae/parasitología , ADN Protozoario/genética , Perros , Filariasis Linfática/veterinaria , Variación Genética , Humanos , Filogenia , Vigilancia de la Población , Sri LankaRESUMEN
BACKGROUND: Malaria was eliminated from Sri Lanka in 2012, and since then 50-60 imported malaria cases have been reported yearly. The country has remained malaria-free since, except for a single case of indigenous malaria in 2018. Blood donors are routinely screened for malaria, and transfusion malaria has not been reported in the country since 1966. CASE PRESENTATION: A 17-year-old splenectomized beta thalassaemia patient developed a transfusion-induced Plasmodium falciparum malaria infection following a blood transfusion 18 days earlier. The blood donor was an armed forces personnel who returned from South Sudan following a United Nations peace-keeping mission. The blood recipient's malaria infection took a complicated clinical course with elevated liver enzymes, lowered blood pressure and a prolonged parasite clearance time of 7 days but he recovered fully after two courses of artemether-lumefantrine interrupted by a course of intravenous artesunate. The prolonged parasite clearance is likely due to lack of splenic clearance of dead or damaged intra-erythrocytic parasites (due to a splenectomy) rather than to the parasite strain being resistant to artemisinin or the partner drug. This is corroborated by the fact that the blood donor's infection responded to artemether-lumefantrine with parasites being cleared on day 3. The blood donor who had not displayed signs or symptoms of malaria, had been screened for malaria on arrival in Sri Lanka and was negative on both microscopy and RDT. At the point of blood donation a blood smear examined microscopically was also reported negative for malaria, but retrospectively, the preserved smear of the donor's blood was found to contain P. falciparum parasites at a very low density. The donor when tested after the transfusion-induced case was diagnosed, also tested positive for malaria and was treated. CONCLUSIONS: After malaria elimination, transfusion-induced malaria from blood donors returning from malaria endemic countries poses a threat to preventing the re-establishment of the disease. Improved surveillance of arrivals in Sri Lanka from malaria endemic countries using more sensitive methods for screening than microscopy may be required to reduce this risk. More stringent criteria for selecting blood donors, and more effective methods of screening donors for malaria than microscopy may also be necessary.
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Transfusión Sanguínea , Sangre/parasitología , Malaria Falciparum/complicaciones , Talasemia beta/complicaciones , Adolescente , Humanos , Malaria Falciparum/sangre , Malaria Falciparum/prevención & control , Sri Lanka , Talasemia beta/sangreRESUMEN
BACKGROUND: Malaria is a life-threatening, multisystem disease caused by the plasmodial parasite with a global incidence of approximately 229 million annually. The parasites are known to have unique and crucial interactions with various body tissues during its life cycle, notably the liver, spleen, and recent work has shown the bone marrow to be a reservoir of infection. METHODS: This study is a case series of patients in whom examination of bone marrow revealed malarial parasites. A retrospective record review of 35 parasite-positive bone marrow specimens examined at Aga Khan University Hospital (AKUH), Karachi, Pakistan, over the years 2007 to 2015 was conducted. Bone marrow aspirates were collected as per International Council for Standardization in Haematology (ICSH) guidelines. RESULTS: The median age of patients was 22 years (range 1-75), and 60 % (n = 21) were male. 22 patients had evidence of Plasmodium falciparum, 12 had evidence of Plasmodium vivax and 1 patient had a mixed infection. Gametocytes and trophozoites were the most common stages identified on both peripheral blood and bone marrow examinations. Indications for bone marrow examination included fever of unknown origin and the workup of cytopenias and malignancies. CONCLUSIONS: The incidental finding of Plasmodium in samples of bone marrow suggests the reticuloendothelial system may be regularly harbour these parasites, be the infection acute or chronic in character.
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Médula Ósea/parasitología , Malaria Falciparum/diagnóstico , Malaria Vivax/diagnóstico , Plasmodium falciparum/aislamiento & purificación , Plasmodium vivax/aislamiento & purificación , Adolescente , Adulto , Anciano , Sangre/parasitología , Niño , Preescolar , Femenino , Humanos , Lactante , Malaria Falciparum/parasitología , Malaria Vivax/parasitología , Masculino , Persona de Mediana Edad , Pakistán , Estudios Retrospectivos , Adulto JovenRESUMEN
BACKGROUND: Like other helminths, hookworms (HW) induce a regulatory immune response able to modulate and dampen reactivity of the host to antigens. No data about the evolution of the immune response after treatment are available. We aim to phenotype the regulatory immune response during natural HW infection and its evolution after treatment. METHODOLOGY: Twenty hookworm infected (HW+) and 14 non-infected subjects HW-from endemic area in the periphery of Ho Chi Minh City were included. Blood and feces samples were obtained before, 2 and 4 weeks after treatment with Albendazole 400mg. Additional samples were obtained at 3 and 12 months in the HW+ group. Hematological parameters, Treg (CD4+CD25hiFoxP3hi) and surface molecules (CD39, CD62L, ICOS, PD-1, CD45RA) were measured as well as inflammatory and lymphocytes differentiation cytokines such as IL-1ß, IL-6, IFNγ, IL-4, IL-17, IL-10, IL-2 and TGFß. RESULTS: HW+ subjects showed higher Treg, TregICOS+, Treg PD1-, TregCD62L+ and CD45RA+FoxP3lo resting Treg (rTreg). CD45RA-FoxP3lo non-suppressive Treg cells were also increased. No preferential Th1/Th2 orientation was observed, nor difference for IL-10 between two groups. After treatment, Treg, TregICOS+, TregCD62L+, Treg PD1- and rTreg decreased while IL-4 and IL-6 cytokines increased. CONCLUSION: During HW infection, Treg are increased and characterized by a heterogeneous population: a highly suppressive as well as a non-suppressive T cells phenotype. After treatment, Treg with immune-suppressive phenotype exhibited a decrease parallel to an inflammatory Th2 response.
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Albendazol/administración & dosificación , Ancylostomatoidea/inmunología , Antihelmínticos/administración & dosificación , Infecciones por Uncinaria/tratamiento farmacológico , Linfocitos T Reguladores/inmunología , Células Th2/inmunología , Adulto , Albendazol/farmacología , Animales , Antihelmínticos/farmacología , Sangre/parasitología , Estudios de Casos y Controles , Citocinas/metabolismo , Heces/parasitología , Regulación de la Expresión Génica/efectos de los fármacos , Infecciones por Uncinaria/inmunología , Humanos , Persona de Mediana Edad , Adulto JovenRESUMEN
Latent forms of Plasmodium vivax, called hypnozoites, cause malaria relapses from the liver into the bloodstream and are a major obstacle to malaria eradication. To experimentally assess the impact of a partially protective pre-erythrocytic vaccine on reducing Plasmodium vivax relapses, we developed a liver-humanized mouse model that allows monitoring of relapses directly in the blood. We passively infused these mice with a suboptimal dose of an antibody that targets the circumsporozoite protein prior to challenge with P. vivax sporozoites. Although this regimen did not completely prevent primary infection, antibody-treated mice experienced 62% fewer relapses. The data constitute unprecedented direct experimental evidence that suboptimal efficacy of infection-blocking antibodies, while not completely preventing primary infection, has a pronounced benefit in reducing the number of relapses. These findings suggest that a partially efficacious pre-erythrocytic Plasmodium vivax vaccine can have a disproportionately high impact in positive public health outcomes.
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Sangre/parasitología , Malaria Vivax/parasitología , Plasmodium vivax/crecimiento & desarrollo , Animales , Modelos Animales de Enfermedad , Femenino , Humanos , Hígado/parasitología , Malaria Vivax/sangre , Ratones , Plasmodium vivax/genética , RecurrenciaRESUMEN
Biting midges in the genus Culicoides (Diptera; Ceratopogonidae) are vectors of pathogens that can cause diseases of major economic importance in humans and animals. Identifying host ranges of these biting midges might aid in understanding the complex epidemiology of such diseases, often involving reservoir hosts and multiple species. In this study, we aim to identify bloodmeal origin from engorged female Culicoides biting midges. All bloodfed females were opportunistically collected as part of an ongoing surveillance programme using Onderstepoort light traps in two provinces in South Africa. DNA of individuals was extracted and subjected to PCR targeting the cytochrome B (CytB) gene region of mammals and avians as well as cytochrome oxidase I (COI) for species identification. In total, 21 new reference barcodes were generated for C. bedfordi, C imicola, C. leucosticus, C. magnus, and C. pycnostictus. Seventy-four blood meals were identified, originating from 12 mammal and three avian species. COI sequence data performed well for species delimitation and 54 Culicoides specimens were identified with C. imicola the predominant species identified (41.8%). Generally, Culicoides species feed on a variety of hosts and host availability might be an important factor when selecting a host. Culicoides species thus appear to be opportunistic feeders rather than specialists. This implicates Culicoides as transfer vectors and demonstrates possible transmission routes of arboviruses and other pathogens from wildlife onwards to domestic animals and humans.
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Sangre/parasitología , Ceratopogonidae/clasificación , Citocromos b/genética , Código de Barras del ADN Taxonómico , Complejo IV de Transporte de Electrones/genética , Animales , Arbovirus/fisiología , Ceratopogonidae/genética , Femenino , Especificidad del Huésped , Humanos , Insectos Vectores/genética , SudáfricaRESUMEN
Artemisinin resistance (ART) has been confirmed in Greater Mekong Sub-region countries. Currently, C580Y mutation on Pfkelch13 gene is known as the molecular marker for the detection of ART. Rapid and accurate detection of ART in field study is essential to guide malaria containment and elimination interventions. A simple method for collection of malaria-infected blood is to spot the blood on filter paper and is fast and easy for transportation and storage in the field study. This study aims to evaluate LAMP-SNP assay for C580Y mutation detection by introducing an extra mismatched nucleotide at the 3' end of the FIP primer. The LAMP-SNP assay was performed in a water bath held at a temperature of 56°C for 45 min. LAMP-SNP products were interpreted by both gel-electrophoresis and HNB-visualized changes in color. The method was then tested with 120 P. falciparum DNA from dried blood spot samples. In comparing the LAMP-SNP assay results with those from DNA sequencing of the clinical samples, the 2 results fully agreed to detect C580Y. The sensitivity and specificity of the LAMP-SNP assay showed 100%. There were no cross-reactions with other Plasmodium species and other Pfkelch13 mutations. The LAMP-SNP assay performed in this study was rapid, reliable, and useful in detecting artemisinin resistance in the field study.