Acta tropica最新文献

Designing a Multi-Epitope Vaccine Candidate for Visceral Leishmaniasis Targeting Leishmania and Sand Fly Vector Antigens: An In Silico Approach

IF 2.1 3区医学 Q2 PARASITOLOGY

Acta tropica

Pub Date : 2025-04-01 DOI: 10.1016/j.actatropica.2025.107600

Manas Ranjan Dikhit , A. Pranav , Ajay Kumar , Abhik Sen

Leishmania donovani, which is responsible for visceral leishmaniasis (VL), poses severe public health challenges, necessitating novel strategies to decrease its incidence. The epitopes predicted with immune informatics tools provide the opportunity for the development of a good vaccine candidate. The immunogenicity of sand fly salivary proteins SP02, SP12, SP13, SP14, SP15, SP19, and SP56 and known Leishmania MHC class I and class II epitopes was evaluated. Among the sand fly salivary proteins the most prominent ten B cell epitopes based on their immunogenicity, stability and safety were derived from these proteins. Two remarkable vaccination candidates that were considered safe, SP14 and SP15, were “LPTILAHSPAGASVNQ” (1.244) and “RLLIKDYVVTRKVVKD" (1.178), respectively. These T cell epitopes included thirteen verified MHC I and six MHC class II epitopes. All known immunodominant epitopes were used in the vaccine build together with possible linkers and an adjuvant at the N-terminus to improve immunogenicity. The proposed vaccine was extensively tested to establish its stability, non-allergic reaction, and nontoxicity, all of which were confirmed.The vaccine construct's stable interaction with TLR4 highlighted important hydrogen bonds necessary for stable receptor engagement. Indicative of a robust Th1 response, immune simulations showed an elivated IgG and IgM titers, substantial helper and cytotoxic T-cell responses, and elevated levels of IFN-γ, IL-2, and IL-12, further supporting the vaccine construct's potential as a promising candidate for leishmaniasis control. However, experimental validations will determine its potential as an effective vaccine candidate.

{"title":"Designing a Multi-Epitope Vaccine Candidate for Visceral Leishmaniasis Targeting Leishmania and Sand Fly Vector Antigens: An In Silico Approach","authors":"Manas Ranjan Dikhit , A. Pranav , Ajay Kumar , Abhik Sen","doi":"10.1016/j.actatropica.2025.107600","DOIUrl":"10.1016/j.actatropica.2025.107600","url":null,"abstract":"<div><div><em>Leishmania donovani,</em> which is responsible for visceral leishmaniasis (VL), poses severe public health challenges, necessitating novel strategies to decrease its incidence. The epitopes predicted with immune informatics tools provide the opportunity for the development of a good vaccine candidate. The immunogenicity of sand fly salivary proteins SP02, SP12, SP13, SP14, SP15, SP19, and SP56 and known <em>Leishmania</em> MHC class I and class II epitopes was evaluated. Among the sand fly salivary proteins the most prominent ten B cell epitopes based on their immunogenicity, stability and safety were derived from these proteins. Two remarkable vaccination candidates that were considered safe, SP14 and SP15, were “LPTILAHSPAGASVNQ” (1.244) and “RLLIKDYVVTRKVVKD\" (1.178), respectively. These T cell epitopes included thirteen verified MHC I and six MHC class II epitopes. All known immunodominant epitopes were used in the vaccine build together with possible linkers and an adjuvant at the N-terminus to improve immunogenicity. The proposed vaccine was extensively tested to establish its stability, non-allergic reaction, and nontoxicity, all of which were confirmed<em>.</em>The vaccine construct's stable interaction with TLR4 highlighted important hydrogen bonds necessary for stable receptor engagement. Indicative of a robust Th1 response, immune simulations showed an elivated IgG and IgM titers, substantial helper and cytotoxic T-cell responses, and elevated levels of IFN-γ, IL-2, and IL-12, further supporting the vaccine construct's potential as a promising candidate for leishmaniasis control. However, experimental validations will determine its potential as an effective vaccine candidate.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"264 ","pages":"Article 107600"},"PeriodicalIF":2.1,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143741801","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

Receptor-regulated smads (R-Smads) in the liver fluke Fasciola gigantica: Characterization, comparative sequence analysis, and life stage-specific expression

IF 2.1 3区医学 Q2 PARASITOLOGY

Acta tropica

Pub Date : 2025-04-01 DOI: 10.1016/j.actatropica.2025.107603

Ornampai Japa , Chorpaka Phuangsri , Khuruwan Klinbumrung , Khanuengnij Prakhammin

The transforming growth factor-beta (TGF-β) signaling pathway is a key conserved developmental pathway, demonstrating remarkable conservation in its components, structures, and functions across diverse animal species. This study presents a comprehensive characterization and comparative analysis of receptor-regulated Smads (R-Smads) in Fasciola gigantica, a major parasite affecting cattle, buffalo, and ruminants in tropical regions. Four R-Smads were identified: FgSmad1/5, FgSmad2, FgSmad3, and FgSmad8. Full-length cDNAs for these R-Smads, isolated using the rapid amplification of cDNA ends (RACE) approach, were 3348, 3010, 5172, and 1991 bp in length, encoding proteins of 464, 506, 678, and 404 amino acids, respectively. FgSmad1/5 and FgSmad8 were classified as bone morphogenetic protein (BMP)-specific R-Smads (BR-Smads) due to their conserved signature motifs and similarity to those found in parasitic platyhelminths and mammalian hosts. Conversely, FgSmad2 and FgSmad3 were identified as TGF-β/activin-specific R-Smads (AR-Smads), displaying a distinctive pattern of conserved motifs commonly observed among trematode parasites. Notably, FgSmad2 exhibited an atypical feature for R-Smads, as it lacked the MH1 domain. The expressions of F. gigantica R-Smad genes were observed across all developmental stages, with the highest levels of most R-Smads occurring in the unembryonated egg stage (primarily BR-Smads) and the metacercaria stage (predominantly AR-Smads), underscoring a significant shift in TGF-β and BMP signaling dynamics during development. These findings greatly advance our understanding of R-Smad proteins within the TGF-β signaling pathway of F. gigantica and provide a solid foundation for future research into their roles and regulatory mechanisms.

{"title":"Receptor-regulated smads (R-Smads) in the liver fluke Fasciola gigantica: Characterization, comparative sequence analysis, and life stage-specific expression","authors":"Ornampai Japa , Chorpaka Phuangsri , Khuruwan Klinbumrung , Khanuengnij Prakhammin","doi":"10.1016/j.actatropica.2025.107603","DOIUrl":"10.1016/j.actatropica.2025.107603","url":null,"abstract":"<div><div>The transforming growth factor-beta (TGF-β) signaling pathway is a key conserved developmental pathway, demonstrating remarkable conservation in its components, structures, and functions across diverse animal species. This study presents a comprehensive characterization and comparative analysis of receptor-regulated Smads (R-Smads) in <em>Fasciola gigantica</em>, a major parasite affecting cattle, buffalo, and ruminants in tropical regions. Four R-Smads were identified: FgSmad1/5, FgSmad2, FgSmad3, and FgSmad8. Full-length cDNAs for these R-Smads, isolated using the rapid amplification of cDNA ends (RACE) approach, were 3348, 3010, 5172, and 1991 bp in length, encoding proteins of 464, 506, 678, and 404 amino acids, respectively. FgSmad1/5 and FgSmad8 were classified as bone morphogenetic protein (BMP)-specific R-Smads (BR-Smads) due to their conserved signature motifs and similarity to those found in parasitic platyhelminths and mammalian hosts. Conversely, FgSmad2 and FgSmad3 were identified as TGF-β/activin-specific R-Smads (AR-Smads), displaying a distinctive pattern of conserved motifs commonly observed among trematode parasites. Notably, FgSmad2 exhibited an atypical feature for R-Smads, as it lacked the MH1 domain. The expressions of <em>F. gigantica R-Smad</em> genes were observed across all developmental stages, with the highest levels of most <em>R-Smads</em> occurring in the unembryonated egg stage (primarily BR-Smads) and the metacercaria stage (predominantly AR-Smads), underscoring a significant shift in TGF-β and BMP signaling dynamics during development. These findings greatly advance our understanding of R-Smad proteins within the TGF-β signaling pathway of <em>F. gigantica</em> and provide a solid foundation for future research into their roles and regulatory mechanisms.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"264 ","pages":"Article 107603"},"PeriodicalIF":2.1,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143741805","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

Rapid molecular method for early detection of the invasive mosquito Aedes aegypti (Linnaeus, 1762) at Points of Entry

IF 2.1 3区医学 Q2 PARASITOLOGY

Acta tropica

Pub Date : 2025-04-01 DOI: 10.1016/j.actatropica.2025.107605

Michela Menegon , Francesco Severini , Luciano Toma , Marco Martignoni , Marco Di Luca

In recent years, globalization and climate change have led to a rise in the number of imported cases of Aedes-diseases in Europe, resulting in increased frequency and magnitude of local transmissions due to the presence of competent vectors. Recently, Italy has experienced the establishment of three exotic Aedes mosquitoes relevant to human health, Aedes albopictus, Aedes koreicus and Aedes japonicus. Aedes aegypti, the primary vector of dengue and yellow fever, distributed in tropical and subtropical regions, has recently reappeared in Europe and the risk for its re-introduction in Italy is high given the climatic conditions suitable for the species.

To address the risk of introduction and spread of Aedes-diseases, the Health Authorities recommend the strengthening of entomological surveillance at regional level, particularly in strategic areas and Points of Entry, such as ports and airports.

In 2021, a Korean research team developed a multiplex-PCR assay for the identification of six Aedini species, not including Ae. aegypti. In the present study, the previous diagnostic test was improved by designing reverse primers for the identification of Ae. aegypti and Aedes geniculatus. This latter native mosquito lays eggs morphologically similar to those of invasive species with which it can sometimes be found in sympatry. Furthermore, a ten-minute DNA extraction method was implemented. The results obtained demonstrate a perfect diagnostic capacity and sensitivity of the method in discriminating the five species tested.

Here, findings of a sensitive, rapid and cost-effective molecular assay developed for the early identification of invasive species at high-risk sites are shown.

{"title":"Rapid molecular method for early detection of the invasive mosquito Aedes aegypti (Linnaeus, 1762) at Points of Entry","authors":"Michela Menegon , Francesco Severini , Luciano Toma , Marco Martignoni , Marco Di Luca","doi":"10.1016/j.actatropica.2025.107605","DOIUrl":"10.1016/j.actatropica.2025.107605","url":null,"abstract":"<div><div>In recent years, globalization and climate change have led to a rise in the number of imported cases of <em>Aedes</em>-diseases in Europe, resulting in increased frequency and magnitude of local transmissions due to the presence of competent vectors. Recently, Italy has experienced the establishment of three exotic <em>Aedes</em> mosquitoes relevant to human health, <em>Aedes albopictus, Aedes koreicus</em> and <em>Aedes japonicus. Aedes aegypti,</em> the primary vector of dengue and yellow fever, distributed in tropical and subtropical regions, has recently reappeared in Europe and the risk for its re-introduction in Italy is high given the climatic conditions suitable for the species.</div><div>To address the risk of introduction and spread of <em>Aedes</em>-diseases, the Health Authorities recommend the strengthening of entomological surveillance at regional level, particularly in strategic areas and Points of Entry, such as ports and airports.</div><div>In 2021, a Korean research team developed a multiplex-PCR assay for the identification of six Aedini species, not including <em>Ae. aegypti</em>. In the present study, the previous diagnostic test was improved by designing reverse primers for the identification of <em>Ae. aegypti</em> and <em>Aedes geniculatus</em>. This latter native mosquito lays eggs morphologically similar to those of invasive species with which it can sometimes be found in sympatry. Furthermore, a ten-minute DNA extraction method was implemented. The results obtained demonstrate a perfect diagnostic capacity and sensitivity of the method in discriminating the five species tested.</div><div>Here, findings of a sensitive, rapid and cost-effective molecular assay developed for the early identification of invasive species at high-risk sites are shown.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"264 ","pages":"Article 107605"},"PeriodicalIF":2.1,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143750527","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

Epidemiological and molecular typing of dengue viruses circulating in Jorhat district, Assam, India

IF 2.1 3区医学 Q2 PARASITOLOGY

Acta tropica

Pub Date : 2025-04-01 DOI: 10.1016/j.actatropica.2025.107588

Barbi Gogoi , Pinkee Phukon , Sima Kumari Dutta , Angshurekha Das , Uttara Borkakoty , Purnima Barua

Background

Dengue is a significant mosquito-borne infection that causes public health concern, particularly in tropical and subtropical regions. This study aimed to characterize the molecular typing of dengue viruses in Jorhat district, as information on dengue serotypes is scarce in India.

Methods

A total of 1359 serum samples of clinically suspected dengue cases were tested for non-structural protein 1 (NS1) antigen and Immunoglobulin M (IgM) antibody using enzyme-linked immunosorbent assay (ELISA). Additionally, viral RNA was extracted from positive samples for multiplex reverse transcriptase-polymerase chain reaction (RT-PCR) to determine the dengue serotypes. Seasonal variations, gender, and age-wise incidences were also studied. Statistical analysis was performed to assess demographic and clinical characteristics.

Results

This study depicts a substantial burden of dengue, with 370 (27.22 %) positive samples. IgM and NS1 ELISA tested positive for 42 (11.3 %) and 328 (88.6 %) samples. Dengue virus (DENV) cases predominantly affected males (58.4 %) and the age group of 16–30 years. The major clinical manifestations include fever, headache, and body aches. Serotyping revealed DENV-2 as the predominant serotype, followed by DENV-3 and DENV-1. The co-infection of DENV-2 and DENV-3 was observed in many cases. Seasonal clustering of dengue cases indicates the highest peak in September and October.

Conclusions

This study provides valuable insights into the epidemiology, diagnosis, and serotyping of dengue viruses in the Jorhat district of Assam, emphasizing the need for continued surveillance and effective vector control measures that should be implemented to mitigate the early detection of dengue in this region.

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引用次数: 0

Cost-effectiveness of dengue control strategies in Bangladesh: An optimal control and ACER-ICER analysis

IF 2.1 3区医学 Q2 PARASITOLOGY

Acta tropica

Pub Date : 2025-04-01 DOI: 10.1016/j.actatropica.2025.107587

Faizunnesa Khondaker , Md. Kamrujjaman , Md. Shahidul Islam

The prevalence of the dengue virus in Bangladesh is extensive, significantly contributing to both illness and death. Managing outbreaks of dengue fever poses a challenge in tropical regions like Bangladesh, where consistently warm temperatures allow mosquitoes to breed and the virus to proliferate. This study introduces a deterministic model with four compartments to represent the transmission of the dengue virus, with parameters estimated using the 2023 outbreak data in Bangladesh. Utilizing the next generation method, we calculate the basic reproduction number

(R_{b})

and conduct sensitivity analysis to explore how various model parameters impact the transmission and spread of dengue in the population. Furthermore, personal protective measures and treatment are incorporated into our proposed model. Numerical simulations are conducted, using the average cost-effectiveness ratio (ACER) and the incremental cost-effectiveness ratio (ICER) to assess the cost-effectiveness of different control strategies, focusing on different control measures with varying cost weights. The findings demonstrate that the combined application of controls avert more infections at a minimal expenses. Additionally, there is a reciprocal relationship between the extent of control efforts and cost weights.

{"title":"Cost-effectiveness of dengue control strategies in Bangladesh: An optimal control and ACER-ICER analysis","authors":"Faizunnesa Khondaker , Md. Kamrujjaman , Md. Shahidul Islam","doi":"10.1016/j.actatropica.2025.107587","DOIUrl":"10.1016/j.actatropica.2025.107587","url":null,"abstract":"<div><div>The prevalence of the dengue virus in Bangladesh is extensive, significantly contributing to both illness and death. Managing outbreaks of dengue fever poses a challenge in tropical regions like Bangladesh, where consistently warm temperatures allow mosquitoes to breed and the virus to proliferate. This study introduces a deterministic model with four compartments to represent the transmission of the dengue virus, with parameters estimated using the 2023 outbreak data in Bangladesh. Utilizing the next generation method, we calculate the basic reproduction number <span><math><mrow><mo>(</mo><msub><mrow><mi>R</mi></mrow><mrow><mi>b</mi></mrow></msub><mo>)</mo></mrow></math></span> and conduct sensitivity analysis to explore how various model parameters impact the transmission and spread of dengue in the population. Furthermore, personal protective measures and treatment are incorporated into our proposed model. Numerical simulations are conducted, using the average cost-effectiveness ratio (ACER) and the incremental cost-effectiveness ratio (ICER) to assess the cost-effectiveness of different control strategies, focusing on different control measures with varying cost weights. The findings demonstrate that the combined application of controls avert more infections at a minimal expenses. Additionally, there is a reciprocal relationship between the extent of control efforts and cost weights.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"264 ","pages":"Article 107587"},"PeriodicalIF":2.1,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143738794","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

Aedes albopictus responses to transfluthrin-impregnated polyester fabric in a semi-field system at different time periods

IF 2.1 3区医学 Q2 PARASITOLOGY

Acta tropica

Pub Date : 2025-04-01 DOI: 10.1016/j.actatropica.2025.107596

Jutamas Kerdsawang , Alex Ahebwa , Ratchadawan Ngoen-Klan , Jeffrey Hii , Theeraphap Chareonviriyaphap

Volatile pyrethroid spatial repellents produce airborne chemicals that cause insect repellency and provide personal protection to human users. This study investigated the effect of a passive emanator fabric on the human landing catch (HLC) of Aedes albopictus in a semi-field system (SFS) as well as post-exposure blood-feeding behavior, fecundity, and egg hatchability. A polyester fabric measuring 1029 cm² impregnated with 2.5 g/m² transfluthrin (TFT) (6.8 %, w/v) was attached to a black-screened vest to simulate insecticide-treated clothing. Two collectors wearing treated polyester fabric (TFT-P) or untreated fabric conducted HLC from opposite test arenas during morning (06:00–08:00 h) and evening (18:00–20:00 h) trials for 12 days. Recaptured surviving mosquitoes were provided a blood meal for 120 min. The protective efficacy—the percentage reduction of HLC in treatment compared to control—of TFT-P was 60.73 % during the morning trials compared to 31.97 % during the evening trials. Blood feeding was moderately reduced in exposed (37.5 % fed) and unexposed (67.7 % fed) mosquitoes during the morning trials. Similarly, egg hatchability was significantly low in exposed batches (31.2 % hatched) compared to the unexposed (54.5 % hatched) from the morning trials, but not the evening trials. The results highlighted the effect of trial time on TFT-P efficacy, mosquito feeding behavior, and egg hatchability. TFT-P could provide personal protection against Ae. albopictus by preventing bites and offering community protection by reducing feeding propensity. Further open-field tests and evaluations against other mosquito species are needed before public use.

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引用次数: 0

Short-term effect of weather variables on West Nile virus infection in Equids in Spain: A space-time stratified case-crossover design

IF 2.1 3区医学 Q2 PARASITOLOGY

Acta tropica

Pub Date : 2025-04-01 DOI: 10.1016/j.actatropica.2025.107602

Osvaldo Fonseca-Rodríguez , Lola Pailler-García , Aleš Urban , Germán Cáceres , Sebastián Napp , Núria Busquets

West Nile virus (WNV) is an arthropod-borne virus primarily transmitted by Culex mosquitoes, among birds, but occasionally infecting humans and equids. Understanding environmental factors on the disease occurrence is crucial for planning effective prevention and control strategies. Our study estimates the short-term effects of ambient temperature, relative humidity and precipitation on weekly cases of WNV in equids in Spain, using a space-time stratified case-crossover design. Because WNV transmission occurs sometime after the weather conditions become favorable for the vector, we aimed to estimate the lagged effect of the three weather variables on the incidence of WNV cases in equids. Therefore, we applied a conditional Poisson regression within the framework of lag-distributed models. These models are particularly effective for examining the delayed effects of exposures. The incidence of WNV confirmed cases was associated with temperatures registered within the prior two and eight weeks. The highest incidence was observed at lag four, where the incident rate ratio (IRR) increased to 11.96 (95 % CI: 9.84–50.40) with mean temperature at 33 °C, likewise relative humidity effect peaked also at lag four (IRR=3.99; 95 % CI: 1.43–11.16) at 93 % of relative humidity. On the other hand, the confidence intervals for precipitation were very wide, making it difficult to discern a clear change in the risk of WNV infection associated with total precipitation. This study sheds light on the complex relationships between meteorological variables and the incidence of WNV cases. Considering the zoonotic nature of the disease, these results could provide valuable information for surveillance and early warning of the disease.

{"title":"Short-term effect of weather variables on West Nile virus infection in Equids in Spain: A space-time stratified case-crossover design","authors":"Osvaldo Fonseca-Rodríguez , Lola Pailler-García , Aleš Urban , Germán Cáceres , Sebastián Napp , Núria Busquets","doi":"10.1016/j.actatropica.2025.107602","DOIUrl":"10.1016/j.actatropica.2025.107602","url":null,"abstract":"<div><div>West Nile virus (WNV) is an arthropod-borne virus primarily transmitted by <em>Culex</em> mosquitoes, among birds, but occasionally infecting humans and equids. Understanding environmental factors on the disease occurrence is crucial for planning effective prevention and control strategies. Our study estimates the short-term effects of ambient temperature, relative humidity and precipitation on weekly cases of WNV in equids in Spain, using a space-time stratified case-crossover design. Because WNV transmission occurs sometime after the weather conditions become favorable for the vector, we aimed to estimate the lagged effect of the three weather variables on the incidence of WNV cases in equids. Therefore, we applied a conditional Poisson regression within the framework of lag-distributed models. These models are particularly effective for examining the delayed effects of exposures. The incidence of WNV confirmed cases was associated with temperatures registered within the prior two and eight weeks. The highest incidence was observed at lag four, where the incident rate ratio (IRR) increased to 11.96 (95 % CI: 9.84–50.40) with mean temperature at 33 °C, likewise relative humidity effect peaked also at lag four (IRR=3.99; 95 % CI: 1.43–11.16) at 93 % of relative humidity. On the other hand, the confidence intervals for precipitation were very wide, making it difficult to discern a clear change in the risk of WNV infection associated with total precipitation. This study sheds light on the complex relationships between meteorological variables and the incidence of WNV cases. Considering the zoonotic nature of the disease, these results could provide valuable information for surveillance and early warning of the disease.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"264 ","pages":"Article 107602"},"PeriodicalIF":2.1,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143727366","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

Seroprevalence of Chlamydia abortus infection in Tibetan sheep in Qinghai Province, China

IF 2.1 3区医学 Q2 PARASITOLOGY

Acta tropica

Pub Date : 2025-04-01 DOI: 10.1016/j.actatropica.2025.107593

Fan Lei , Jiali Yu , Yaqian Niu , Te Ba , Lin Liang

Chlamydia abortus (C. abortus) is an obligate intracellular, Gram-negative bacterium, causing ovine enzootic abortion (OEA). No data about C. abortus infection are available in Tibetan sheep in Qinghai, China. A total of 1043 Tibetan sheep serum samples were collected from 8 regions in Qinghai, China, and for specific antibodies against C. abortus using a commercial ELISA Kit. The results showed that the overall seroprevalence of C. abortus in Tibetan sheep was 153/1043 (14.7 %, 95 % confidence interval [CI] 12.5–16.8). The prevalence in female and male Tibetan sheep was 58/421 (13.8 %, 95 % CI 10.5–17.1) and 95/622 (15.3 %, 95 % CI 18.6–26.6), respectively with no significant difference (P > 0.05). The seroprevalence of antibodies to C. abortus in Tibetan sheep ranged from 10.0 to 21.7 % among the eight different areas, and the difference was also without statistical significance. The prevalence among different age groups ranged from 14.0 to 16.5 %, with a higher prevalence among 1 to 1.5 years age category. The results demonstrate the presence of C. abortus infection in Tibetan sheep in Qinghai and its potential impact on public health and the local Tibetan economy. To our knowledge, this is the first seroprevalence survey of C. abortus in Tibetan sheep in Qinghai, China.

{"title":"Seroprevalence of Chlamydia abortus infection in Tibetan sheep in Qinghai Province, China","authors":"Fan Lei , Jiali Yu , Yaqian Niu , Te Ba , Lin Liang","doi":"10.1016/j.actatropica.2025.107593","DOIUrl":"10.1016/j.actatropica.2025.107593","url":null,"abstract":"<div><div><em>Chlamydia abortus</em> (<em>C. abortus</em>) is an obligate intracellular, Gram-negative bacterium, causing ovine enzootic abortion (OEA). No data about <em>C. abortus</em> infection are available in Tibetan sheep in Qinghai, China. A total of 1043 Tibetan sheep serum samples were collected from 8 regions in Qinghai, China, and for specific antibodies against <em>C. abortus</em> using a commercial ELISA Kit. The results showed that the overall seroprevalence of <em>C. abortus</em> in Tibetan sheep was 153/1043 (14.7 %, 95 % confidence interval [CI] 12.5–16.8). The prevalence in female and male Tibetan sheep was 58/421 (13.8 %, 95 % CI 10.5–17.1) and 95/622 (15.3 %, 95 % CI 18.6–26.6), respectively with no significant difference (<em>P</em> > 0.05). The seroprevalence of antibodies to <em>C. abortus</em> in Tibetan sheep ranged from 10.0 to 21.7 % among the eight different areas, and the difference was also without statistical significance. The prevalence among different age groups ranged from 14.0 to 16.5 %, with a higher prevalence among 1 to 1.5 years age category. The results demonstrate the presence of <em>C. abortus</em> infection in Tibetan sheep in Qinghai and its potential impact on public health and the local Tibetan economy. To our knowledge, this is the first seroprevalence survey of <em>C. abortus</em> in Tibetan sheep in Qinghai, China.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"264 ","pages":"Article 107593"},"PeriodicalIF":2.1,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143746642","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

Exposure to three zoonotic pathogens in the pig population of Southern Italy

IF 2.1 3区医学 Q2 PARASITOLOGY

Acta tropica

Pub Date : 2025-04-01 DOI: 10.1016/j.actatropica.2025.107607

Gianmarco Ferrara , Nebyou Moje , Antonella Rossi , Ugo Pagnini , Giuseppe Iovane , Serena Montagnaro

Pigs represent a reservoir of infectious diseases that can be transmitted to humans through feeding or close contact. The aim of this study was to evaluate the seroprevalence of three zoonotic pathogens (Brucella suis, Mycobacterium avium, and Paslahepevirus balayani, also called hepatitis E virus) in the swine population in the Campania region, Southern Italy. A total of 370 animals from 31 farms were sampled and tested with specific commercial ELISAs. Antibodies against hepatitis E virus were detected in 41.4 % of the animals and in almost all the farms (83.8 %). Mycobacterium avium and Brucella suis were less widespread (seroprevalences of 3.5 % and 0 % at the individual level, 32.3 % and 0 % at the farm level, respectively). The univariate analysis of risk factors showed that sex (males), location (Naples), age (growers and finishers), farm size, and system (intensive) were related to higher hepatitis E virus prevalences. We also found higher seroprevalences in pigs belonging to districts where bovines were the main ruminant species. This variable and age were confirmed as risk factors also in multivariate analysis. The data obtained highlighted how pigs are HEV reservoirs also in southern Italy and that pigs in this region are also exposed to Mycobacterium avium but not to Brucella suis.

{"title":"Exposure to three zoonotic pathogens in the pig population of Southern Italy","authors":"Gianmarco Ferrara , Nebyou Moje , Antonella Rossi , Ugo Pagnini , Giuseppe Iovane , Serena Montagnaro","doi":"10.1016/j.actatropica.2025.107607","DOIUrl":"10.1016/j.actatropica.2025.107607","url":null,"abstract":"<div><div>Pigs represent a reservoir of infectious diseases that can be transmitted to humans through feeding or close contact. The aim of this study was to evaluate the seroprevalence of three zoonotic pathogens (<em>Brucella suis, Mycobacterium avium</em>, and <em>Paslahepevirus balayani</em>, also called hepatitis E virus) in the swine population in the Campania region, Southern Italy. A total of 370 animals from 31 farms were sampled and tested with specific commercial ELISAs. Antibodies against hepatitis E virus were detected in 41.4 % of the animals and in almost all the farms (83.8 %). <em>Mycobacterium avium</em> and <em>Brucella suis</em> were less widespread (seroprevalences of 3.5 % and 0 % at the individual level, 32.3 % and 0 % at the farm level, respectively). The univariate analysis of risk factors showed that sex (males), location (Naples), age (growers and finishers), farm size, and system (intensive) were related to higher hepatitis E virus prevalences. We also found higher seroprevalences in pigs belonging to districts where bovines were the main ruminant species. This variable and age were confirmed as risk factors also in multivariate analysis. The data obtained highlighted how pigs are HEV reservoirs also in southern Italy and that pigs in this region are also exposed to <em>Mycobacterium avium</em> but not to <em>Brucella suis</em>.</div></div>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":"264 ","pages":"Article 107607"},"PeriodicalIF":2.1,"publicationDate":"2025-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143750488","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

A systematic literature review of the efficacy of acaricidal plants, plant extracts, and tick assays used against dog-associated ticks.

IF 2.1 3区医学 Q2 PARASITOLOGY

Acta tropica

Pub Date : 2025-03-30 DOI: 10.1016/j.actatropica.2025.107608

G G Molaba, P K Thethe, L J Shai, Omm Thekisoe, K Mtshali

Dogs are an integral part of many households and important companion animals to humans. Their inquisitive and exploratory behaviour leads them to roam natural environments, making them susceptible to tick infestations that can also be transmitted to humans. To control these ticks, various plant extracts have been evaluated for their efficacy as acaricides and/or repellents against various species. This study was aimed at consolidating the data that has been published in terms of the plant species that have shown efficacy against ticks that parasitize dogs, it further evaluated the methods used in these formulations. A keyword-Boolean strategy was created to extract a total of n = 103 articles that were included in the study. The leading countries in terms of the global distribution of acaricidal plant investigation outputs were Brazil at 23%, India at 17% and Turkey at 7%. A total of n = 13 tick species were used in the evaluated studies. The dog tick Rhipicephalus sanguineus was the most widely used for efficacy testing at 43% frequency. The Lamiaceae plant family had the highest frequency for reported use across the evaluated studies at 18%, this was followed by the family Asteraceae at 11%. Adult immersion test, larval packet test and larval immersion test were the most preferred assays for acaricidal efficacy studies. Leaves were the most preferred plant parts utilized for crude plant metabolites extraction (n = 43), while essential oils were the most highly reported extracts (n = 60). Lastly, extracts were primarily subjected to Gas chromatography for analysis of the plant compounds (n = 38). This paper gives the current global status of potential acaricidal plants utilized against ticks parasitizing dogs.

{"title":"A systematic literature review of the efficacy of acaricidal plants, plant extracts, and tick assays used against dog-associated ticks.","authors":"G G Molaba, P K Thethe, L J Shai, Omm Thekisoe, K Mtshali","doi":"10.1016/j.actatropica.2025.107608","DOIUrl":"https://doi.org/10.1016/j.actatropica.2025.107608","url":null,"abstract":"<p><p>Dogs are an integral part of many households and important companion animals to humans. Their inquisitive and exploratory behaviour leads them to roam natural environments, making them susceptible to tick infestations that can also be transmitted to humans. To control these ticks, various plant extracts have been evaluated for their efficacy as acaricides and/or repellents against various species. This study was aimed at consolidating the data that has been published in terms of the plant species that have shown efficacy against ticks that parasitize dogs, it further evaluated the methods used in these formulations. A keyword-Boolean strategy was created to extract a total of n = 103 articles that were included in the study. The leading countries in terms of the global distribution of acaricidal plant investigation outputs were Brazil at 23%, India at 17% and Turkey at 7%. A total of n = 13 tick species were used in the evaluated studies. The dog tick Rhipicephalus sanguineus was the most widely used for efficacy testing at 43% frequency. The Lamiaceae plant family had the highest frequency for reported use across the evaluated studies at 18%, this was followed by the family Asteraceae at 11%. Adult immersion test, larval packet test and larval immersion test were the most preferred assays for acaricidal efficacy studies. Leaves were the most preferred plant parts utilized for crude plant metabolites extraction (n = 43), while essential oils were the most highly reported extracts (n = 60). Lastly, extracts were primarily subjected to Gas chromatography for analysis of the plant compounds (n = 38). This paper gives the current global status of potential acaricidal plants utilized against ticks parasitizing dogs.</p>","PeriodicalId":7240,"journal":{"name":"Acta tropica","volume":" ","pages":"107608"},"PeriodicalIF":2.1,"publicationDate":"2025-03-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143762784","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