Acta tropica最新文献_第4页

Natural infection with Trypanosoma cruzi and feeding habits of Triatominae (Hemiptera: Reduviidae) from the state of Durango, Mexico

IF 2.1 3区医学 Q2 PARASITOLOGY

Acta tropica

Pub Date : 2025-02-11 DOI: 10.1016/j.actatropica.2025.107555

Rosa Lilián Gómez-Palacios , Karina Ruiz-Tovar , Herón Huerta , Mario Octavio González-Reyes , Irma Padilla-Medina , Jorge Luis de-la-Rosa-Arana , Salvador Fonseca-Coronado

Chagas disease is a chronic and systemic condition caused by the protozoan Trypanosoma cruzi, acquired via abrasions or wounds on the skin or mucous membranes, through contact with feces or urine of hematophagous bugs belonging to the family Reduviidae, subfamily Triatominae. Many regions in Mexico are endemic for Chagas disease, but entomological and parasitological data are still limited. This study identified the incidence of natural infection with T. cruzi, as well as the feeding habits of the different species of triatomines circulating in the state of Durango, in the north-central region of Mexico. One hundred and ninety triatomines were taxonomically identified between February 2023 and May 2024 and a sample of intestinal content was obtained to identify the presence of T. cruzi by using microscopy and endpoint PCR. In addition, a 382 bp product of vertebrate cytochrome B (CytB) was amplified and sequenced to obtain the profile of feeding habits of this triatomines. Of the specimens collected, 121 were adults and 69 nymphs ranging from stage I to stage V. Of the collected adults, 115 were identified as Triatoma longipennis and 6 as Triatoma recurva. The specimens were collected both indoors (116) and in the peridomicile (74) showing a high overall percentage of positivity to natural infection with T.cruzi (54.5 %). Considering the total number of specimens collected, the colonization index was 36.32 %. In 27 of the 190 samples (14.22 %) CytB was amplified, revealing humans as the main feeding source for the triatomines. Our findings reveal that both species of triatomines were infected and predominantly found indoors, with humans as their primary feeding source. Comprehensive knowledge of the behavior of triatomine species that transmit T. cruzi allows their integrated control and the implementation of molecular tools for precise identification that strengthens the algorithms for epidemiological surveillance.

{"title":"Natural infection with Trypanosoma cruzi and feeding habits of Triatominae (Hemiptera: Reduviidae) from the state of Durango, Mexico","authors":"Rosa Lilián Gómez-Palacios , Karina Ruiz-Tovar , Herón Huerta , Mario Octavio González-Reyes , Irma Padilla-Medina , Jorge Luis de-la-Rosa-Arana , Salvador Fonseca-Coronado","doi":"10.1016/j.actatropica.2025.107555","DOIUrl":"10.1016/j.actatropica.2025.107555","url":null,"abstract":"<div><div>Chagas disease is a chronic and systemic condition caused by the protozoan <em>Trypanosoma cruzi</em>, acquired via abrasions or wounds on the skin or mucous membranes, through contact with feces or urine of hematophagous bugs belonging to the family Reduviidae, subfamily Triatominae. Many regions in Mexico are endemic for Chagas disease, but entomological and parasitological data are still limited. This study identified the incidence of natural infection with <em>T. cruzi,</em> as well as the feeding habits of the different species of triatomines circulating in the state of Durango, in the north-central region of Mexico. One hundred and ninety triatomines were taxonomically identified between February 2023 and May 2024 and a sample of intestinal content was obtained to identify the presence of <em>T. cruzi</em> by using microscopy and endpoint PCR<em>.</em> In addition, a 382 bp product of vertebrate cytochrome B (CytB) was amplified and sequenced to obtain the profile of feeding habits of this triatomines. Of the specimens collected, 121 were adults and 69 nymphs ranging from stage I to stage V. Of the collected adults, 115 were identified as <em>Triatoma longipennis</em> and 6 as <em>Triatoma recurva</em>. The specimens were collected both indoors (116) and in the peridomicile (74) showing a high overall percentage of positivity to natural infection with <em>T.cruzi</em> (54.5 %). Considering the total number of specimens collected, the colonization index was 36.32 %. In 27 of the 190 samples (14.22 %) CytB was amplified, revealing humans as the main feeding source for the triatomines. Our findings reveal that both species of triatomines were infected and predominantly found indoors, with humans as their primary feeding source. Comprehensive knowledge of the behavior of triatomine species that transmit <em>T. cruzi</em> allows their integrated control and the implementation of molecular tools for precise identification that strengthens the algorithms for epidemiological surveillance.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"263 ","pages":"Article 107555"},"PeriodicalIF":2.1,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143412849","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Seasonal dynamics of Amblyomma ticks in South America: A meta-analytical approach

IF 2.1 3区医学 Q2 PARASITOLOGY

Acta tropica

Pub Date : 2025-02-11 DOI: 10.1016/j.actatropica.2025.107552

Rafael M. Nascimento , Renato C. Macedo-Rego , Ralph Maturano , Kátia M. Famadas

In this study, we carried out a detailed analysis of the seasonality of ticks of the genus Amblyomma in the Neotropical region by means of a meta-analysis. Our aim was to identify temporal patterns and factors that influence the seasonality of these ectoparasites, considering different developmental stages (larvae, nymphs and adults) to provide a comprehensive understanding of the population dynamics of this group. To do this, we carried out a systematic review in databases such as Scopus and Web of Science. Studies that assessed the prevalence, abundance, or seasonality of Amblyomma ticks in the Neotropical region were included in our data collection. Despite our focus on the Neotropics, we only obtained data on South American populations. Multilevel meta-analytical models were used to test whether larvae, nymphs and adults of Amblyomma ticks show higher mean abundance, mean intensity and prevalence in the dry or in the rainy season. Our results validate that Amblyomma larvae, nymphs, and adults show distinct patterns of seasonality. During the dry season, larvae and nymphs occur more frequently, while adults predominate in the rainy season. We also observed variations in seasonal occurrence at the species level, highlighting the complexity and variability of these patterns. Thus, in summary, the data we provide here contributes to a better understanding on the temporal distribution of these ectoparasites, as well as the factors contributing for such distribution, thus providing subsidies for the development of more effective strategies for the control and prevention of tick-borne diseases. By showing research gaps in the literature, we also argue that further research on the seasonal patterns of ticks is needed to improve our understanding of the factors that influence the population dynamics of these parasites and to implementing more effective public health measures.

{"title":"Seasonal dynamics of Amblyomma ticks in South America: A meta-analytical approach","authors":"Rafael M. Nascimento , Renato C. Macedo-Rego , Ralph Maturano , Kátia M. Famadas","doi":"10.1016/j.actatropica.2025.107552","DOIUrl":"10.1016/j.actatropica.2025.107552","url":null,"abstract":"<div><div>In this study, we carried out a detailed analysis of the seasonality of ticks of the genus <em>Amblyomma</em> in the Neotropical region by means of a meta-analysis. Our aim was to identify temporal patterns and factors that influence the seasonality of these ectoparasites, considering different developmental stages (larvae, nymphs and adults) to provide a comprehensive understanding of the population dynamics of this group. To do this, we carried out a systematic review in databases such as <em>Scopus</em> and <em>Web of Science</em>. Studies that assessed the prevalence, abundance, or seasonality of <em>Amblyomma</em> ticks in the Neotropical region were included in our data collection. Despite our focus on the Neotropics, we only obtained data on South American populations. Multilevel meta-analytical models were used to test whether larvae, nymphs and adults of <em>Amblyomma</em> ticks show higher mean abundance, mean intensity and prevalence in the dry or in the rainy season. Our results validate that <em>Amblyomma</em> larvae, nymphs, and adults show distinct patterns of seasonality. During the dry season, larvae and nymphs occur more frequently, while adults predominate in the rainy season. We also observed variations in seasonal occurrence at the species level, highlighting the complexity and variability of these patterns. Thus, in summary, the data we provide here contributes to a better understanding on the temporal distribution of these ectoparasites, as well as the factors contributing for such distribution, thus providing subsidies for the development of more effective strategies for the control and prevention of tick-borne diseases. By showing research gaps in the literature, we also argue that further research on the seasonal patterns of ticks is needed to improve our understanding of the factors that influence the population dynamics of these parasites and to implementing more effective public health measures.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"263 ","pages":"Article 107552"},"PeriodicalIF":2.1,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143412913","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Molecular evidence of Bartonella spp. in biting midges of the genus Culicoides Latreille (Diptera: Ceratopogonidae) from Brazil

IF 2.1 3区医学 Q2 PARASITOLOGY

Acta tropica

Pub Date : 2025-02-10 DOI: 10.1016/j.actatropica.2025.107553

Paulo Vitor Cadina Arantes , Israel de Souza Pinto , Maria Clara Alves Santarém , Maria Luiza Felippe-Bauer , Daniel Antônio Braga Lee , Rosangela Zacarias Machado , Marcos Rogério André

Bartonella spp. are typical vector-borne pathogens, whose transmission has been primarily associated with a wide variety of hematophagous arthropods. These bacteria are responsible for several clinical syndromes in both humans and animals. The present study aimed to investigate the occurrence and molecular identity of Bartonella spp. in 345 specimens of Culicoides Latreille from the Brazilian Amazon. Out of 345 Culicoides specimens collected in the Amazon National Park, state of Pará, northern Brazil, 86.7 % (299/345) were positive for the endogenous cytochrome c oxidase subunit 1 gene. We detected a 24 % (72/299) prevalence rate for Bartonella spp. using a quantitative real-time PCR targeting the 16S-23S rRNA internal transcribed spacer (ITS) region. Culicoides foxi was statistically more associated with Bartonella positivity when compared to C. hylas and C. leopoldoi. Culicoides specimens collected at the ground level were more associated with positivity for Bartonella spp. when compared to those collected at the canopy. Further molecular characterization was performed using conventional PCR assays targeting seven molecular markers (nuoG, gltA, groEL, ftsZ, rpoB, pap31, and ribC). The BLASTn analysis revealed four gltA sequences with 99.72–100 % identity to Bartonella bovis previously detected in cattle from Brazil. One ribC sequence showed 100 % identity to Bartonella henselae previously detected in a cat from Germany. Six pap31 sequences showed 90–91 % identity to a Bartonella sp. sequence previously detected in a bat (Carollia perspicillata) from Brazil. This study represents the first molecular evidence of Bartonella spp. DNA in biting midges and contributes to understanding their role in the epidemiological cycles of these agents.

{"title":"Molecular evidence of Bartonella spp. in biting midges of the genus Culicoides Latreille (Diptera: Ceratopogonidae) from Brazil","authors":"Paulo Vitor Cadina Arantes , Israel de Souza Pinto , Maria Clara Alves Santarém , Maria Luiza Felippe-Bauer , Daniel Antônio Braga Lee , Rosangela Zacarias Machado , Marcos Rogério André","doi":"10.1016/j.actatropica.2025.107553","DOIUrl":"10.1016/j.actatropica.2025.107553","url":null,"abstract":"<div><div><em>Bartonella</em> spp. are typical vector-borne pathogens, whose transmission has been primarily associated with a wide variety of hematophagous arthropods. These bacteria are responsible for several clinical syndromes in both humans and animals. The present study aimed to investigate the occurrence and molecular identity of <em>Bartonella</em> spp. in 345 specimens of <em>Culicoides</em> Latreille from the Brazilian Amazon. Out of 345 <em>Culicoides</em> specimens collected in the Amazon National Park, state of Pará, northern Brazil, 86.7 % (299/345) were positive for the endogenous cytochrome c oxidase subunit 1 gene. We detected a 24 % (72/299) prevalence rate for <em>Bartonella</em> spp. using a quantitative real-time PCR targeting the 16S-23S rRNA internal transcribed spacer (ITS) region. <em>Culicoides foxi</em> was statistically more associated with <em>Bartonella</em> positivity when compared to <em>C. hylas</em> and C. <em>leopoldoi. Culicoides</em> specimens collected at the ground level were more associated with positivity for <em>Bartonella</em> spp. when compared to those collected at the canopy. Further molecular characterization was performed using conventional PCR assays targeting seven molecular markers (<em>nuoG, gltA, groEL, ftsZ, rpoB, pap31</em>, and <em>ribC</em>). The BLASTn analysis revealed four <em>gltA</em> sequences with 99.72–100 % identity to <em>Bartonella bovis</em> previously detected in cattle from Brazil. One <em>ribC</em> sequence showed 100 % identity to <em>Bartonella henselae</em> previously detected in a cat from Germany. Six <em>pap31</em> sequences showed 90–91 % identity to a <em>Bartonella</em> sp. sequence previously detected in a bat (<em>Carollia perspicillata</em>) from Brazil. This study represents the first molecular evidence of <em>Bartonella</em> spp. DNA in biting midges and contributes to understanding their role in the epidemiological cycles of these agents.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"263 ","pages":"Article 107553"},"PeriodicalIF":2.1,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143405224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Viral metagenomics of hematophagous insects collected in the Carajas mining complex, Pará State, Brazil

IF 2.1 3区医学 Q2 PARASITOLOGY

Acta tropica

Pub Date : 2025-02-10 DOI: 10.1016/j.actatropica.2025.107551

Camila Margalho Braga , Sandro Patroca da Silva , Joaquim Pinto Nunes Neto , Daniele Barbosa de Almeida Medeiros , Ana Cecília Ribeiro Cruz , Bruna Laís Sena do Nascimento , Lucas Rafael Santana Pinheiro , Lívia Carício Martins

Hematophagous insects are vectors of viruses that cause diseases in humans and animals worldwide. Mosquitoes (Culicidae), biting midges (Ceratopogonidae), and sandflies (Psychodidae) were collected in three municipalities (Marabá, Canaã dos Carajás, and Curionópolis) in the state of Pará, Brazil, in 2019. Morphological keys were used for the taxonomic identification of insect species. High-throughput sequencing and metagenomic analysis were employed to characterize the viromes of the hematophagous insects. We characterized the virome of 839 insects grouped into 14 pools. A total of 729 million paired reads were generated, with 12 million viral sequences (3 % of the reads). The families Reoviridae, Myoviridae, Retroviridae, and Poxviridae were found in all samples of this study. Phylogenies of RNA-dependent RNA polymerase (RdRp) from viruses of the families Chuviridae, Dicistroviridae, Flaviviridae, Iflaviridae, Mesoniviridae, Phenuiviridae, and Rhabdoviridae were performed. In this study, the first isolation of the Guaico Culex Virus (GCXV) in the northern region of Brazil was obtained from a pool of Culex (Melanoconion) spp. mosquitoes collected in Curionópolis. The data obtained in this study demonstrate that the Carajás region has an ecosystem rich in viruses. Additional studies are needed to understand the dynamics of viruses in vectors, vertebrates, and the human population in the region.

{"title":"Viral metagenomics of hematophagous insects collected in the Carajas mining complex, Pará State, Brazil","authors":"Camila Margalho Braga , Sandro Patroca da Silva , Joaquim Pinto Nunes Neto , Daniele Barbosa de Almeida Medeiros , Ana Cecília Ribeiro Cruz , Bruna Laís Sena do Nascimento , Lucas Rafael Santana Pinheiro , Lívia Carício Martins","doi":"10.1016/j.actatropica.2025.107551","DOIUrl":"10.1016/j.actatropica.2025.107551","url":null,"abstract":"<div><div>Hematophagous insects are vectors of viruses that cause diseases in humans and animals worldwide. Mosquitoes (<em>Culicidae</em>), biting midges (<em>Ceratopogonidae</em>), and sandflies (<em>Psychodidae</em>) were collected in three municipalities (Marabá, Canaã dos Carajás, and Curionópolis) in the state of Pará, Brazil, in 2019. Morphological keys were used for the taxonomic identification of insect species. High-throughput sequencing and metagenomic analysis were employed to characterize the viromes of the hematophagous insects. We characterized the virome of 839 insects grouped into 14 pools. A total of 729 million paired reads were generated, with 12 million viral sequences (3 % of the reads). The families <em>Reoviridae, Myoviridae, Retroviridae</em>, and <em>Poxviridae</em> were found in all samples of this study. Phylogenies of RNA-dependent RNA polymerase (RdRp) from viruses of the families <em>Chuviridae, Dicistroviridae, Flaviviridae, Iflaviridae, Mesoniviridae, Phenuiviridae,</em> and <em>Rhabdoviridae</em> were performed. In this study, the first isolation of the <em>Guaico Culex Virus</em> (GCXV) in the northern region of Brazil was obtained from a pool of <em>Culex (Melanoconion)</em> spp. mosquitoes collected in Curionópolis. The data obtained in this study demonstrate that the Carajás region has an ecosystem rich in viruses. Additional studies are needed to understand the dynamics of viruses in vectors, vertebrates, and the human population in the region.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"263 ","pages":"Article 107551"},"PeriodicalIF":2.1,"publicationDate":"2025-02-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143405247","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Accuracy of diagnostic tests for feline sporotrichosis: A systematic review and meta-analysis

IF 2.1 3区医学 Q2 PARASITOLOGY

Acta tropica

Pub Date : 2025-02-09 DOI: 10.1016/j.actatropica.2025.107549

Eric L Domingos , Dalton A Souza , Fernando M S Alves , Daniela Gorski , Fernanda S Tonin , Luana M Ferreira , Roberto Pontarolo

Background

Feline sporotrichosis is a subcutaneous infection caused by fungi of the Sporothrix genus, particularly concerning in endemic regions of South America, where cats are important vectors. Traditional diagnosis through fungal culture is time-consuming, which can delay the start of treatment.

Objective

Our goal was to synthesize the evidence on the accuracy of alternative diagnostic methods for feline sporotrichosis.

Methods

A systematic review was conducted following the Cochrane Collaboration recommendations and the PRISMA-DTA checklist (CRD42023456520). Searches for observational studies were performed in PubMed, Embase, and Web of Science. Using a random-effects model, bivariate meta-analysis was employed to estimate combined sensitivity, specificity, and diagnostic odds ratio (DOR) with 95 % confidence intervals. The results were presented in forest plots and Summary Receiver Operating Characteristic (SROC) curves; heterogeneity was assessed using Tau² and I² statistics (R-software).

Results

Eight studies, totaling 1,920 cats, evaluated five diagnostic methods. PCR tests had the highest accuracy (90 % sensitivity, 94 % specificity, area under the curve 0.950), while cytological methods demonstrated moderate diagnostic accuracy (89 %, 22 % and 0.879, respectively). The findings highlight the need for faster, more accurate, and cost-effective diagnostic alternatives, especially in resource-limited regions, and underscore the importance of advancing techniques to improve early detection and treatment of sporotrichosis.

{"title":"Accuracy of diagnostic tests for feline sporotrichosis: A systematic review and meta-analysis","authors":"Eric L Domingos , Dalton A Souza , Fernando M S Alves , Daniela Gorski , Fernanda S Tonin , Luana M Ferreira , Roberto Pontarolo","doi":"10.1016/j.actatropica.2025.107549","DOIUrl":"10.1016/j.actatropica.2025.107549","url":null,"abstract":"<div><h3>Background</h3><div>Feline sporotrichosis is a subcutaneous infection caused by fungi of the <em>Sporothrix</em> genus, particularly concerning in endemic regions of South America, where cats are important vectors. Traditional diagnosis through fungal culture is time-consuming, which can delay the start of treatment.</div></div><div><h3>Objective</h3><div>Our goal was to synthesize the evidence on the accuracy of alternative diagnostic methods for feline sporotrichosis.</div></div><div><h3>Methods</h3><div>A systematic review was conducted following the Cochrane Collaboration recommendations and the PRISMA-DTA checklist (CRD42023456520). Searches for observational studies were performed in PubMed, Embase, and Web of Science. Using a random-effects model, bivariate meta-analysis was employed to estimate combined sensitivity, specificity, and diagnostic odds ratio (DOR) with 95 % confidence intervals. The results were presented in forest plots and Summary Receiver Operating Characteristic (SROC) curves; heterogeneity was assessed using Tau² and I² statistics (R-software).</div></div><div><h3>Results</h3><div>Eight studies, totaling 1,920 cats, evaluated five diagnostic methods. PCR tests had the highest accuracy (90 % sensitivity, 94 % specificity, area under the curve 0.950), while cytological methods demonstrated moderate diagnostic accuracy (89 %, 22 % and 0.879, respectively). The findings highlight the need for faster, more accurate, and cost-effective diagnostic alternatives, especially in resource-limited regions, and underscore the importance of advancing techniques to improve early detection and treatment of sporotrichosis.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"263 ","pages":"Article 107549"},"PeriodicalIF":2.1,"publicationDate":"2025-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143387070","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Metabolomic analysis of larval stages of Onchocerca japonica (Spirurida: Onchocercidae), raised in black fly (Diptera: Simuliidae) vectors, by gas chromatography-tandem mass spectrometry 利用气相色谱-串联质谱法对在黑蝇（双翅目：蚋科）载体中饲养的日本盘尾丝虫（螺旋体：盘尾丝虫科）幼虫阶段进行代谢组学分析。

IF 2.1 3区医学 Q2 PARASITOLOGY

Acta tropica

Pub Date : 2025-02-09 DOI: 10.1016/j.actatropica.2025.107541

Masako Fukuda , Yasushi Otsuka , Kumiko Sakai , Shigehiko Uni , Kerstin Junker , Atiporn Saeung , Wichai Srisuka , Hiroyuki Takaoka

To monitor and prevent the spread of zoonotic onchocerciasis, identification of the natural vectors (blood-sucking insects) of its causative agents, Onchocerca species, is crucial. To date, vector identification depends on the detection of infective third-stage larvae in insects by traditional dissection. We aimed to develop a novel, more efficient method for the discrimination of the four larval stages, i.e. microfilariae (Mf), first-stage larvae (L1), second-stage larvae (L2), and third-stage larvae (L3), of O. japonica by metabolomic analysis. Microfilariae of O. japonica, the causative agent of zoonotic onchocerciasis in Japan, were obtained from skin snips of wild boars and injected into newly-emerged black flies (Diptera: Simuliidae) to enable further larval development. Metabolites obtained from Mf, L1, L2, and L3 were analyzed using a gas chromatography-tandem mass spectrometer. Multivariate analysis of the data of metabolites showed the complete separation of the four larval stages. The highest level of acetoacetic acid and hydroxylamine was found in Mf and L3, respectively. Consequently, we propose that hydroxylamine is a potential marker to detect infective larvae of O. japonica in natural infections and could be a valuable tool in vector surveys, transmission studies and epidemiological surveys.

{"title":"Metabolomic analysis of larval stages of Onchocerca japonica (Spirurida: Onchocercidae), raised in black fly (Diptera: Simuliidae) vectors, by gas chromatography-tandem mass spectrometry","authors":"Masako Fukuda , Yasushi Otsuka , Kumiko Sakai , Shigehiko Uni , Kerstin Junker , Atiporn Saeung , Wichai Srisuka , Hiroyuki Takaoka","doi":"10.1016/j.actatropica.2025.107541","DOIUrl":"10.1016/j.actatropica.2025.107541","url":null,"abstract":"<div><div>To monitor and prevent the spread of zoonotic onchocerciasis, identification of the natural vectors (blood-sucking insects) of its causative agents, <em>Onchocerca</em> species, is crucial. To date, vector identification depends on the detection of infective third-stage larvae in insects by traditional dissection. We aimed to develop a novel, more efficient method for the discrimination of the four larval stages, i.e. microfilariae (Mf), first-stage larvae (L1), second-stage larvae (L2), and third-stage larvae (L3), of <em>O. japonica</em> by metabolomic analysis. Microfilariae of <em>O. japonica</em>, the causative agent of zoonotic onchocerciasis in Japan, were obtained from skin snips of wild boars and injected into newly-emerged black flies (Diptera: Simuliidae) to enable further larval development. Metabolites obtained from Mf, L1, L2, and L3 were analyzed using a gas chromatography-tandem mass spectrometer. Multivariate analysis of the data of metabolites showed the complete separation of the four larval stages. The highest level of acetoacetic acid and hydroxylamine was found in Mf and L3, respectively. Consequently, we propose that hydroxylamine is a potential marker to detect infective larvae of <em>O. japonica</em> in natural infections and could be a valuable tool in vector surveys, transmission studies and epidemiological surveys.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"263 ","pages":"Article 107541"},"PeriodicalIF":2.1,"publicationDate":"2025-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143397751","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Insights into spatio-temporal dynamics of Anopheles vectors while approaching malaria elimination along the Thailand-Cambodia border

IF 2.1 3区医学 Q2 PARASITOLOGY

Acta tropica

Pub Date : 2025-02-09 DOI: 10.1016/j.actatropica.2025.107545

Manop Saeung , Natapong Jupatanakul , Aneta Afelt , Kittitat Suksirisawat , Suthat Lhaosudto , Alex Ahebwa , Jeffrey Hii , Sylvie Manguin , Theeraphap Chareonviriyaphap

The international borders of Thailand are well recognized as areas with high malaria transmission risk. Although Sisaket Province, bordering Cambodia, is recognized as a malaria-prone area, major progress towards malaria elimination has been made. In fact, this province was ranked as having high malaria incidence in Thailand decades ago, increasing its potential for malaria re-establishment. To devise a re-establishment strategy, this work investigated the spatio-temporal dynamics of Anopheles and examined the malariogenic potential of villages in Sisaket Province. Human landing catches (HLCs) were recorded to collect adult mosquitoes from village and rubber-forest ecotypes between 18.00 and 06.00 h. The collection was conducted for two years based on four consecutive nights per season in the rainy, cool-dry, and hot-dry seasons during July 2022–March 2024, for a total of 24 nights. Based on the results, Anopheles dirus s.s. was the primary malaria vector and predominant in the rubber-forest areas, where positive larval habitats were found. Its biting peaks were observed between 21.00 and 22.00 h across seasons and years. The abundance of An. dirus was correlated positively with the amount of rainfall at two months (R = 0.89) and three months (R = 0.95) after the rainfall. Therefore, public health interventions to prevent outdoor biting should target rubber tappers and forest-goers two–three months after the rainy season. In addition, risk assessment of malaria re-establishment suggested a high potential based on the malariogenic potential scores. Thus, ongoing action is important to control any re-establishment to achieve sustainable malaria elimination in Sisaket Province.

{"title":"Insights into spatio-temporal dynamics of Anopheles vectors while approaching malaria elimination along the Thailand-Cambodia border","authors":"Manop Saeung , Natapong Jupatanakul , Aneta Afelt , Kittitat Suksirisawat , Suthat Lhaosudto , Alex Ahebwa , Jeffrey Hii , Sylvie Manguin , Theeraphap Chareonviriyaphap","doi":"10.1016/j.actatropica.2025.107545","DOIUrl":"10.1016/j.actatropica.2025.107545","url":null,"abstract":"<div><div>The international borders of Thailand are well recognized as areas with high malaria transmission risk. Although Sisaket Province, bordering Cambodia, is recognized as a malaria-prone area, major progress towards malaria elimination has been made. In fact, this province was ranked as having high malaria incidence in Thailand decades ago, increasing its potential for malaria re-establishment. To devise a re-establishment strategy, this work investigated the spatio-temporal dynamics of <em>Anopheles</em> and examined the malariogenic potential of villages in Sisaket Province. Human landing catches (HLCs) were recorded to collect adult mosquitoes from village and rubber-forest ecotypes between 18.00 and 06.00 h. The collection was conducted for two years based on four consecutive nights per season in the rainy, cool-dry, and hot-dry seasons during July 2022–March 2024, for a total of 24 nights. Based on the results, <em>Anopheles dirus</em> s.s. was the primary malaria vector and predominant in the rubber-forest areas, where positive larval habitats were found. Its biting peaks were observed between 21.00 and 22.00 h across seasons and years. The abundance of <em>An. dirus</em> was correlated positively with the amount of rainfall at two months (<em>R</em> = 0.89) and three months (<em>R</em> = 0.95) after the rainfall. Therefore, public health interventions to prevent outdoor biting should target rubber tappers and forest-goers two–three months after the rainy season. In addition, risk assessment of malaria re-establishment suggested a high potential based on the malariogenic potential scores. Thus, ongoing action is important to control any re-establishment to achieve sustainable malaria elimination in Sisaket Province.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"263 ","pages":"Article 107545"},"PeriodicalIF":2.1,"publicationDate":"2025-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143397750","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Histopathology and immunohistochemistry findings in kidney and urinary bladder of rabies virus-infected mice

IF 2.1 3区医学 Q2 PARASITOLOGY

Acta tropica

Pub Date : 2025-02-08 DOI: 10.1016/j.actatropica.2025.107550

Sara de Souza Pereira , Cássia Nazaré de Sousa Moraes , Vinicius Pacheco , Érika Dayane Leal Rodrigues , Victor Gabriel Bastos Chaves , Marcella Katheryne Marques Bernal , Roberta Nicole de Oliveira Mota , Ranna Taynara dos Reis Sousa , Adriana Maciel de Castro Cardoso Jaques , Jorge Rodrigues de Sousa , Livia Medeiros Neves Casseb

Rabies virus (RABV) is a lethal and neglected zoonosis responsible for over 60,000 deaths annually caused by the neurotropic virus Lyssavirus rabies. Although rabies is well-known for its severe nervous system impairment, little is known regarding the specific alterations caused in extraneural organs. Studies suggest an essential involvement of RABV in the kidneys. However, the extent of the pathological damage caused by RABV in this organ remains to be understood. This study describes the histopathological alterations and RABV antigen expression in the kidneys and urinary bladder. Viral immunostaining was observed, suggesting that RABV can successfully infect these tissues. In addition, the main alterations found in the kidneys were edema in the convoluted tubules and in the glomerulus, interstitial inflammation, atrophy of the glomerular tuft, a decrease in Bowman's capsule and Bowman's space, and the accumulation of glycogen in the tubules, which may indicate the effects of inflammation caused by RABV. Therefore, our results showed the importance of understanding the effects of histopathological alterations induced by RABV and the need for more studies concerning the inflammatory action of the virus during the infection.

{"title":"Histopathology and immunohistochemistry findings in kidney and urinary bladder of rabies virus-infected mice","authors":"Sara de Souza Pereira , Cássia Nazaré de Sousa Moraes , Vinicius Pacheco , Érika Dayane Leal Rodrigues , Victor Gabriel Bastos Chaves , Marcella Katheryne Marques Bernal , Roberta Nicole de Oliveira Mota , Ranna Taynara dos Reis Sousa , Adriana Maciel de Castro Cardoso Jaques , Jorge Rodrigues de Sousa , Livia Medeiros Neves Casseb","doi":"10.1016/j.actatropica.2025.107550","DOIUrl":"10.1016/j.actatropica.2025.107550","url":null,"abstract":"<div><div>Rabies virus (RABV) is a lethal and neglected zoonosis responsible for over 60,000 deaths annually caused by the neurotropic virus <em>Lyssavirus rabies</em>. Although rabies is well-known for its severe nervous system impairment, little is known regarding the specific alterations caused in extraneural organs. Studies suggest an essential involvement of RABV in the kidneys. However, the extent of the pathological damage caused by RABV in this organ remains to be understood. This study describes the histopathological alterations and RABV antigen expression in the kidneys and urinary bladder. Viral immunostaining was observed, suggesting that RABV can successfully infect these tissues. In addition, the main alterations found in the kidneys were edema in the convoluted tubules and in the glomerulus, interstitial inflammation, atrophy of the glomerular tuft, a decrease in Bowman's capsule and Bowman's space, and the accumulation of glycogen in the tubules, which may indicate the effects of inflammation caused by RABV. Therefore, our results showed the importance of understanding the effects of histopathological alterations induced by RABV and the need for more studies concerning the inflammatory action of the virus during the infection.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"263 ","pages":"Article 107550"},"PeriodicalIF":2.1,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143389851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Big Six: Vertebrate host interactions as significant transmission drivers of bovine trypanosomosis in Nigeria – A systematic review and meta-analysis

IF 2.1 3区医学 Q2 PARASITOLOGY

Acta tropica

Pub Date : 2025-02-07 DOI: 10.1016/j.actatropica.2025.107547

Paul Olalekan Odeniran , Kehinde Foluke Paul-Odeniran , Aanuoluwapo Olalekan Odeyemi , Isaiah Oluwafemi Ademola

Bovine trypanosomosis remains a significant challenge in Nigeria due to the widespread presence of tsetse and biting flies. Despite numerous control interventions, livestock owners continue to face the burden of high treatment costs year-round. Holistic management has been elusive, largely due to the interconnected roles of the "Big-Six" animal hosts in sustaining transmission dynamics. This study conducted a systematic review of publications from Web of Science, Ovid MEDLINE, PubMed, Google Scholar, and AJOL Online databases, following PRISMA guidelines between 2000 and 2024. Eligible studies reported trypanosomosis prevalence in cattle, small ruminants, dogs, pigs, camels, and wildlife. Subgroup analyses by breed, sex, and diagnostic techniques were performed, with point estimates evaluated at a 95 % confidence interval (CI). A total of 80 studies involving 25,171 animals were included, revealing average prevalence of 38.2 % (95 % CI: 31.4–45.3) in wildlife, pooled prevalence of 12.0 % (95 % CI: 3.0–25.1) in cattle, with 11.7 % specifically observed in trypanotolerant cattle breeds, 4.6 % (2.3–7.6) in small ruminants, 9.6 % (95 % CI: 1.9–21.5) in dogs, 10.4 % (95 % CI: 5.6–16.3) in pigs, and 28.0 % (95 % CI: 18.5–38.6) in camels. Wildlife exhibited distinct ecological patterns, while ovine and caprine data clustered closely. These findings explain the critical role of vertebrate hosts, along with bovine herd management practices, in perpetuating disease transmission within susceptible cattle populations. Effective control requires treating vertebrate hosts harbouring trypanosomes within or surrounding bovine herds and the use of insecticide-impregnated nets, alongside fencing cattle herds from forest edges. This integrated approach is essential to achieving the elimination of African animal trypanosomosis (AAT) in Nigeria and across Africa.

{"title":"Big Six: Vertebrate host interactions as significant transmission drivers of bovine trypanosomosis in Nigeria – A systematic review and meta-analysis","authors":"Paul Olalekan Odeniran , Kehinde Foluke Paul-Odeniran , Aanuoluwapo Olalekan Odeyemi , Isaiah Oluwafemi Ademola","doi":"10.1016/j.actatropica.2025.107547","DOIUrl":"10.1016/j.actatropica.2025.107547","url":null,"abstract":"<div><div>Bovine trypanosomosis remains a significant challenge in Nigeria due to the widespread presence of tsetse and biting flies. Despite numerous control interventions, livestock owners continue to face the burden of high treatment costs year-round. Holistic management has been elusive, largely due to the interconnected roles of the \"Big-Six\" animal hosts in sustaining transmission dynamics. This study conducted a systematic review of publications from Web of Science, Ovid MEDLINE, PubMed, Google Scholar, and AJOL Online databases, following PRISMA guidelines between 2000 and 2024. Eligible studies reported trypanosomosis prevalence in cattle, small ruminants, dogs, pigs, camels, and wildlife. Subgroup analyses by breed, sex, and diagnostic techniques were performed, with point estimates evaluated at a 95 % confidence interval (CI). A total of 80 studies involving 25,171 animals were included, revealing average prevalence of 38.2 % (95 % CI: 31.4–45.3) in wildlife, pooled prevalence of 12.0 % (95 % CI: 3.0–25.1) in cattle, with 11.7 % specifically observed in trypanotolerant cattle breeds, 4.6 % (2.3–7.6) in small ruminants, 9.6 % (95 % CI: 1.9–21.5) in dogs, 10.4 % (95 % CI: 5.6–16.3) in pigs, and 28.0 % (95 % CI: 18.5–38.6) in camels. Wildlife exhibited distinct ecological patterns, while ovine and caprine data clustered closely. These findings explain the critical role of vertebrate hosts, along with bovine herd management practices, in perpetuating disease transmission within susceptible cattle populations. Effective control requires treating vertebrate hosts harbouring trypanosomes within or surrounding bovine herds and the use of insecticide-impregnated nets, alongside fencing cattle herds from forest edges. This integrated approach is essential to achieving the elimination of African animal trypanosomosis (AAT) in Nigeria and across Africa.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"263 ","pages":"Article 107547"},"PeriodicalIF":2.1,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143381435","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Spatio-temporal modeling of Cutaneous Leishmaniasis under climate change scenarios in the Maghreb region (2021–2100)

IF 2.1 3区医学 Q2 PARASITOLOGY

Acta tropica

Pub Date : 2025-02-07 DOI: 10.1016/j.actatropica.2025.107548

Yasmine Saadene, Amina Salhi

Introduction

Climate change presents a significant challenge to global public health, especially regarding vector-borne diseases such as cutaneous leishmaniasis. This study aims to investigate the impact of climate change on the distribution of CL in North Africa, with a focus on Algeria, Tunisia, and Morocco.

Methods

We analyzed historical epidemiological and climatic data from 2000 to 2020 and employed a Generalized Additive Model to assess the influence of climatic variables including temperature, relative humidity, wind speed, and precipitation on CL incidence. Additionally, climate projection data from the Coordinated Regional Climate Downscaling Experiment (CORDEX) under the RCP 2.6 scenario were utilized to predict future CL incidence from 2021 to 2100.

Results

The findings indicate an increase in CL cases in Mediterranean coastal areas, particularly in eastern Tunisia, Algeria, and parts of Morocco, due to rising temperatures and shifting precipitation patterns. The analysis revealed varying temporal peaks in CL incidence across the three countries: short-term for Algeria (2025), mid-term for Morocco (2065), and long-term for Tunisia (2085).

Conclusions

This study underscores the need for region-specific surveillance and response systems and emphasizes the importance of integrating climate forecasts into public health strategies to mitigate the risks of CL spread under changing climatic conditions in North Africa.

{"title":"Spatio-temporal modeling of Cutaneous Leishmaniasis under climate change scenarios in the Maghreb region (2021–2100)","authors":"Yasmine Saadene, Amina Salhi","doi":"10.1016/j.actatropica.2025.107548","DOIUrl":"10.1016/j.actatropica.2025.107548","url":null,"abstract":"<div><h3>Introduction</h3><div>Climate change presents a significant challenge to global public health, especially regarding vector-borne diseases such as cutaneous leishmaniasis. This study aims to investigate the impact of climate change on the distribution of CL in North Africa, with a focus on Algeria, Tunisia, and Morocco.</div></div><div><h3>Methods</h3><div>We analyzed historical epidemiological and climatic data from 2000 to 2020 and employed a Generalized Additive Model to assess the influence of climatic variables including temperature, relative humidity, wind speed, and precipitation on CL incidence. Additionally, climate projection data from the Coordinated Regional Climate Downscaling Experiment (CORDEX) under the RCP 2.6 scenario were utilized to predict future CL incidence from 2021 to 2100.</div></div><div><h3>Results</h3><div>The findings indicate an increase in CL cases in Mediterranean coastal areas, particularly in eastern Tunisia, Algeria, and parts of Morocco, due to rising temperatures and shifting precipitation patterns. The analysis revealed varying temporal peaks in CL incidence across the three countries: short-term for Algeria (2025), mid-term for Morocco (2065), and long-term for Tunisia (2085).</div></div><div><h3>Conclusions</h3><div>This study underscores the need for region-specific surveillance and response systems and emphasizes the importance of integrating climate forecasts into public health strategies to mitigate the risks of CL spread under changing climatic conditions in North Africa.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"263 ","pages":"Article 107548"},"PeriodicalIF":2.1,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143381436","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0