Acta tropica最新文献_第9页

Protective humoral immunity induced by virus-like particles expressing Toxoplasma gondii CST1 or MIC8 表达弓形虫CST1或MIC8的病毒样颗粒诱导的保护性体液免疫。

IF 2.1 3区医学 Q2 PARASITOLOGY

Acta tropica

Pub Date : 2025-01-01 DOI: 10.1016/j.actatropica.2024.107501

Jie Mao , Gi-Deok Eom , Keon-Woong Yoon , Su In Heo , Hae-Ji Kang , Ki Back Chu , Eun-Kyung Moon , Fu-Shi Quan

Protective efficacy assessment of toxoplasmosis vaccines, at least at the preclinical level, frequently involves lethal dose challenge infection. Nonetheless, their efficacies remain largely unexplored against low infection doses which better reflects how humans become infected in the real world. In this study, we compared the immunity elicited in mice that were heterologously immunized with recombinant baculovirus and virus-like particles expressing either the cyst wall protein (CST1) or microneme protein 8 (MIC8) of Toxoplasma gondii (T. gondii). We also investigated how these vaccines fared against both light and heavy infection intensities of T. gondii ME49. Interestingly, under light infection intensity, vaccines expressing CST1 induced significantly higher mucosal antibody responses than MIC8. Germinal center B (GC B) cell responses were elicited to a greater extent following immunization with either antigen, regardless of the infection dose. Similarly, both antigens suppressed IFN-γ production in the brains upon heavy infection. The overall vaccine-induced protection was also similar for the two vaccine antigens under heavy infection. However, in lightly infected mice, CST1 conferred improved GC B cell induction and further inhibited IFN-γ and cyst burden than those elicited by MIC8, thereby contributing to better protection. These findings indicated that light infection could be used to identify optimal vaccine candidates, thus highlighting the impact of infection intensity in vaccine efficacy evaluations.

弓形虫病疫苗的保护功效评估，至少在临床前水平，经常涉及致死剂量挑战感染。尽管如此，它们的功效在很大程度上仍未被探索，以对抗低感染剂量，这更好地反映了人类在现实世界中是如何被感染的。在本研究中，我们比较了重组杆状病毒和表达刚地弓形虫囊壁蛋白（CST1）或微粒蛋白8 （MIC8）的病毒样颗粒异种免疫小鼠的免疫效果。我们还研究了这些疫苗如何抵抗轻度和重度感染强度的弓形虫ME49。有趣的是，在低感染强度下，表达CST1的疫苗诱导的粘膜抗体反应明显高于MIC8。生发中心B （GC B）细胞反应在免疫任一抗原后更大程度上被激发，无论感染剂量如何。同样，在严重感染时，两种抗原都抑制大脑中IFN-γ的产生。在严重感染情况下，两种疫苗抗原的总体疫苗诱导保护作用也相似。然而，在轻度感染小鼠中，与MIC8诱导的相比，CST1改善了GC B细胞的诱导，并进一步抑制IFN-γ和囊肿负荷，从而提供更好的保护。这些发现表明，光感染可用于确定最佳候选疫苗，从而突出感染强度对疫苗疗效评价的影响。

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引用次数: 0

Intra-individual polymorphisms in the mitochondrial COI gene of tick-killing Ixodiphagus wasps parasitizing Haemaphysalis flava ticks 寄生黄血蜱的杀蜱异食蜂线粒体COI基因的个体内多态性。

IF 2.1 3区医学 Q2 PARASITOLOGY

Acta tropica

Pub Date : 2025-01-01 DOI: 10.1016/j.actatropica.2024.107510

Yurie Taya , Yuto Shiraki , Samuel Kelava , Naoki Fujisawa , Yuma Ohari , Mackenzie L. Kwak , Saori Baba , Hideka Numata , Gita Sadaula Pandey , Yuki Ohsugi , Yuki Katada , Shiho Niwa , Shohei Ogata , Keita Matsuno , Nariaki Nonaka , Ryo Nakao

Ixodid ticks are significant vectors of pathogens affecting both humans and animals. Biological control with natural enemies represents a sustainable tool for managing ticks. However, there is a substantial lack of knowledge about the natural enemies of ticks. Wasps of the genus Ixodiphagus (Encyrtidae) are currently the only known tick-specific parasitoids. While these wasps have been sporadically recorded worldwide, their presence in Eastern Asia is poorly documented. In this study, we investigated the occurrence of Ixodiphagus wasps in field-collected ticks reared on rabbits under laboratory conditions. Ticks were collected from the Hokkaido, Hokuriku, Chugoku, Shikoku, and Kyushu regions in Japan. Out of 1,933 Haemaphysalis ticks infested on rabbits, adult wasps emerged from 15 engorged ticks. All the ticks from which wasps emerged were morphologically and molecularly identified as Haemaphysalis flava. Additionally, wasp DNA was detected in unfed H. flava nymphs using a newly designed Ixodiphagus-specific PCR assay. Among nine experimental sites in the Chugoku region, Ixodiphagus wasps were detected at three sites, with parasitism rates ranging from 1.8 % to 8.1 %. Finally, the mitochondrial COI gene sequences of four wasp and two tick samples were characterized using shotgun sequencing, direct sequencing, and in-fusion cloning approaches. Multiple intra-individual polymorphisms were observed in all the tested samples. Further studies are needed to investigate the relationship between Ixodiphagus wasps and Ixodid ticks. An increased understanding of these parasitoid wasps could contribute to future biological control measures against ticks.

粘蜱是影响人类和动物的病原体的重要媒介。利用天敌进行生物防治是一种可持续的蜱虫防治手段。然而，人们对蜱虫的天敌知之甚少。依螨属的黄蜂是目前唯一已知的蜱特有的寄生蜂。虽然这些黄蜂在世界各地都有零星的记录，但它们在东亚的存在却很少有记录。本研究在实验室条件下调查了野外采集的家兔饲养的蜱中蜱虫的发生情况。在日本北海道、北陆、Chugoku、四国和九州地区采集蜱虫。在1933只附着在兔子身上的血蜱中，从15只充血蜱中出现了成年黄蜂。所有产生胡蜂的蜱在形态和分子上都被鉴定为黄血蜱。此外，利用一种新设计的ixodiphagus特异性PCR检测方法，在未饲喂的黄蚜若虫中检测到黄蜂DNA。在中部地区的9个试验点中，有3个试验点检测到异食小蜂，寄生率为1.8% ~ 8.1%。最后，采用散弹枪测序、直接测序和融合克隆等方法对4只黄蜂和2只蜱的线粒体COI基因进行了鉴定。在所有测试样本中均观察到多个个体内多态性。粘虫寄生蜂与粘虫蜱的关系有待进一步研究。增加对这些寄生蜂的了解可能有助于未来对蜱虫的生物控制措施。

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引用次数: 0

Effects of climate change on the distribution of Molossus molossus and the potential risk of Orthohantavirus transmission in the Neotropical region 气候变化对新热带地区鼹鼠鼠分布的影响及正汉坦病毒传播的潜在风险。

IF 2.1 3区医学 Q2 PARASITOLOGY

Acta tropica

Pub Date : 2025-01-01 DOI: 10.1016/j.actatropica.2024.107497

Fernando da Silva Moreira , Gratchela Dutra Rodrigues , Diuliani Fonseca Morales , Maria Rita Donalisio , Frederico Schmitt Kremer , Rodrigo Ferreira Krüger

Molossus molossus is a widely distributed neotropical bat species in the Americas, often found in urban areas. This study evaluated climate change effects on the potential geographic distribution of M. molossus, a natural host of zoonotic pathogens such as Orthohantavirus, in the Neotropical region. Using ecological niche modeling (ENM), models were generated for current (1970–2000) and future (2070) climate scenarios based on two Shared Socioeconomic Pathways (SSP2–4.5 and SSP5–8.5) and two Global Circulation Models (MPI-ESM1–2-LR and IPSL-CM6A-LR). Results indicated that in the current scenario, warm and coastal areas of the Neotropics are suitable for M. molossus occurrence. Risk areas for Orthohantavirus transmission were mapped by overlapping the probability of urban expansion with projections of climatic suitability for the bat. For both future scenarios (2070), projections indicate an expansion of suitable climatic areas for M. molossus over urban expansion zones, specifically in Brazil, Paraguay, Peru, Ecuador, Costa Rica, Honduras, El Salvador, Guatemala, Belize, Mexico, the United States, Cuba, Haiti, the Dominican Republic, and Puerto Rico. However, projections also indicate the Lesser Antilles under climate threat, considering that no climatic suitability areas will remain. These findings provide important information for planning surveillance and mitigation actions for zoonotic risks associated with M. molossus, considering climate change impacts on its geographic distribution in the Neotropical region.

Molossus Molossus是一种广泛分布在美洲的新热带蝙蝠，经常在城市地区发现。本研究评估了气候变化对新热带地区molossus（正汉坦病毒等人畜共患病原体的天然宿主）潜在地理分布的影响。利用生态位模型（ENM），基于两个共享社会经济路径（SSP2-4.5和SSP5-8.5）和两个全球环流模式（MPI-ESM1-2-LR和IPSL-CM6A-LR），建立了当前（1970-2000）和未来（2070）气候情景的模型。结果表明，在当前情景下，暖区和新热带的沿海地区适合鼠唇蝗的生长。通过将城市扩张的概率与蝙蝠的气候适宜性预测重叠，绘制了正汉坦病毒传播的危险区。对于两种未来情景（2070年），预估表明，在城市扩张区，特别是在巴西、巴拉圭、秘鲁、厄瓜多尔、哥斯达黎加、洪都拉斯、萨尔瓦多、危地马拉、伯利兹、墨西哥、美国、古巴、海地、多米尼加共和国和波多黎各，适合molossus生长的气候区域将扩大。然而，考虑到气候适宜地区将不复存在，预测也表明小安的列斯群岛正面临气候威胁。考虑到气候变化对其在新热带地区的地理分布的影响，这些发现为规划与鼹鼠鼠相关的人畜共患风险的监测和缓解行动提供了重要信息。

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引用次数: 0

Modeling of periodic input Ornstein–Uhlenbeck temperature-tick-borne disease transmission coupling mechanism under climate change 气候变化下周期性输入Ornstein-Uhlenbeck温蜱传播耦合机制建模

IF 2.1 3区医学 Q2 PARASITOLOGY

Acta tropica

Pub Date : 2025-01-01 DOI: 10.1016/j.actatropica.2024.107490

Ning Wang, Shengqiang Liu

Given the rapid increase in climate change, investigating the impact of climate change on the transmission mechanism of tick-borne diseases is imperative. In order to fully capture the influence of the seasonal variation of temperature, environmental disturbances and the co-feeding transmission on the spread of tick-borne diseases, we propose a novel stochastic dynamical model that couples the mean-reverting Ornstein–Uhlenbeck temperature equation with periodic input to the tick-borne disease model. Through theoretical analysis, we derive sufficient conditions for the extinction of tick populations and the eradication of tick-borne diseases, as well as the stochastic persistence conditions of the system. In numerical simulations, we find that the periodic Ornstein–Uhlenbeck temperature equation can effectively fit the actual temperature data in low, medium, and high latitude regions of China. In risk assessment, we find that at the spatial perspective, low-latitude areas have a higher risk of tick-borne diseases, requiring enhanced control measures; from a temporal perspective, compared to the past, the current stage presents a greater risk of tick-borne diseases when preventive measures are not implemented. Additionally, we observe that larger noise of environment for tick populations favors the extinction of tick populations, while smaller temperature fluctuations, noise on infected hosts and ticks, as well as higher temperature regression rate, are more likely to lead to the extinction of tick-borne diseases. These findings provide crucial insights into understanding the impact of climate change on the transmission mechanism of tick-borne diseases.

鉴于气候变化的迅速加剧，研究气候变化对蜱传疾病传播机制的影响势在必行。为了充分捕捉季节温度变化、环境干扰和共食传播对蜱传疾病传播的影响，我们提出了一种新的随机动力学模型，该模型将均值回归的Ornstein-Uhlenbeck温度方程与周期性输入耦合到蜱传疾病模型中。通过理论分析，导出了蜱种群灭绝和蜱传疾病根除的充分条件，以及系统的随机持续条件。数值模拟结果表明，周期性的Ornstein-Uhlenbeck温度方程能较好地拟合中国低、中、高纬地区的实际温度数据。风险评估发现，从空间上看，低纬度地区蜱传疾病风险较高，需要加强控制措施；从时间的角度来看，与过去相比，如果不采取预防措施，目前阶段出现蜱传疾病的风险更大。此外，我们观察到蜱种群环境噪声越大，有利于蜱种群的灭绝，而较小的温度波动、受感染宿主和蜱的噪声以及较高的温度回归率更容易导致蜱传疾病的灭绝。这些发现为理解气候变化对蜱传疾病传播机制的影响提供了至关重要的见解。

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引用次数: 0

Modeling the lagged and nonlinear effects of weather conditions on abundance of Culex tarsalis mosquitoes in Saskatchewan, Western Canada using a bi-dimensional distributed lag nonlinear model 利用二维分布滞后非线性模型模拟天气条件对加拿大西部萨斯喀彻温省tarsalis库蚊丰度的滞后和非线性影响。

IF 2.1 3区医学 Q2 PARASITOLOGY

Acta tropica

Pub Date : 2025-01-01 DOI: 10.1016/j.actatropica.2024.107512

Zemichael Gizaw , Cuauhtémoc Tonatiuh Vidrio-Sahagún , Alain Pietroniro , Corinne J. Schuster-Wallace

The establishment of West Nile Virus (WNV) competent vectors continues to pose a major public health challenge in Canada, especially in the south. While studies have examined the association between weather conditions and the abundance of mosquitoes over trap weeks, there is limited research on the effects of weather conditions on the abundance of Culex tarsalis (Cx. tarsalis) mosquitoes for a lapse of time beyond the trap week in Saskatchewan, Western Canada. To address this gap, we analyzed provincially available weekly mosquito trap and co-incident meteorological station data in Saskatchewan from 2010 to 2021 using a bi-dimensional distributed lag and nonlinear model. Data indicate that 171,141 Cx. tarsalis mosquitoes were trapped across much of Saskatchewan, from 2010 to 2021. Cx. tarsalis were found to be most abundant between weeks 26 and 35 (July and August) and peaked in weeks 30 and 31. Based on the WNV-positive pools, mosquito infection rates increased from week 23 to 36. While weekly average maximum air temperatures between 20 °C

and 30 °C were associated with more Cx. tarsalis across all lags (0 – 8 weeks), higher weekly average minimum air temperatures had a strong and immediate effect that diminished over longer lags. Higher weekly average rainfall amounts (> 20 mm) were associated with fewer Cx. tarsalis mosquitoes across all lags, while average weekly rainfall between 8 and 20 mm was strongly associated with a high abundance of Cx. tarsalis mosquitoes over longer lags (5 -7 weeks). Additionally, increasing wind speed was associated with lower abundance of Cx. tarsalis across all lags. Findings identified nonlinear lag associations for weekly average maximum air temperature and rainfall, but linear associations for weekly average minimum air temperature and wind speed. Identified lags and thresholds for temperature, rainfall, and wind speed at which mosquito abundance peaked could help to inform public health authorities in timing of vector control measures to prevent WNV transmission.

在加拿大，特别是在南部，西尼罗病毒（WNV）有能力的媒介的确立继续构成重大的公共卫生挑战。虽然有研究调查了天气条件和捕蚊器周内蚊子数量之间的关系，但关于天气条件对库蚊（库蚊）数量的影响的研究有限。在加拿大西部的萨斯喀彻温省，在捕蚊器一周之后的一段时间里，人们一直在捕捉tarsalis)蚊子。为了解决这一差距，我们使用二维分布滞后和非线性模型分析了萨斯喀彻温省2010年至2021年每周可用的捕蚊器和同期气象站数据。数据显示，171,141 Cx。从2010年到2021年，萨斯喀彻温省的大部分地区都被困住了tarsalis蚊子。残雪。tarsalis在第26 ~ 35周（7 ~ 8月）数量最多，在第30 ~ 31周数量最多。在西尼罗河病毒阳性池中，蚊虫感染率从第23周上升至第36周。而每周平均最高气温在20°C至30°C之间与更多的Cx有关。在所有滞后期（0 - 8周），较高的周平均最低气温具有强烈而直接的影响，但随着滞后时间的延长而减弱。周平均降雨量（20 ~ 20 mm）越高，Cx越少。而平均每周降雨量在8至20毫米之间与Cx的高丰度密切相关。Tarsalis蚊潜伏期较长（5 -7周）。此外，风速的增加与Cx丰度的降低有关。Tarsalis在所有区域。研究发现，周平均最高气温和降雨量存在非线性滞后关系，但周平均最低气温和风速存在线性关联。确定蚊子数量达到峰值的温度、降雨和风速的滞后和阈值，可帮助公共卫生当局掌握预防西尼罗河病毒传播的病媒控制措施的时机。

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引用次数: 0

Epidemiological characteristics and genetic diversity of Bartonella species from rodents in Guangxi Zhuang autonomous region, Southwestern China 广西壮族自治区鼠类巴尔通体流行病学特征及遗传多样性

IF 2.1 3区医学 Q2 PARASITOLOGY

Acta tropica

Pub Date : 2025-01-01 DOI: 10.1016/j.actatropica.2024.107515

Xin-Yan Yao , Chao-Xiang Jia , An-Qi Li , Ting Qin , Dai Peng , Ying-Qian Han , Shuang Guo , Kai Zhong , Guo-Yu Yang , Yue-Ying Wang , He-Ping Li

Bartonella spp. are gram-negative bacteria recognized as zoonotic pathogens of wide spectrum mammals. Rodents are recognized as a natural reservoir of pathogens, and many Bartonella species transmitted by various blood-sucking arthropods have been detected in various rodents populations. In Guangxi Zhuang Autonomous Region, humans have a habit of preying on rodents, however, data on the genetic diversity of Bartonella are still absent. Investigating the epidemiological characteristics of Bartonella infection in rodents is of great significance for the prevention and control of human Bartonellosis. In this study, rodents were captured to monitor the prevalence of Bartonella in four cities in Guangxi Zhuang Autonomous Region, Southwestern China. Six species of Bartonella, including three confirmed zoonotic species, were detected based on the rrs gene with an overall prevalence of 11.5 % (32/278) in rodents. Bartonella tribocorum (21/32, 65.6 %) was the predominant species among the three zoonotic Bartonella species. In addition, phylogenetic and genetic analyses of the rrs, gltA, and rpoB genes indicated that the strains were divided into distinct clade within the same rodent, suggesting the co-circulating of diverse genetic genotypes of Bartonella species. These results provide insights into the prevalence and genetic diversity of Bartonella species circulating in rodents in Guangxi Zhuang Autonomous Region, and also urged the surveillance of rodent-associated Bartonella species in these areas.

巴尔通体是一种革兰氏阴性细菌，是广谱哺乳动物的人畜共患病原体。啮齿动物被认为是病原体的天然储存库，在不同啮齿动物种群中发现了许多由各种吸血节肢动物传播的巴尔通体。在广西壮族自治区，人类有捕食啮齿动物的习惯，然而，关于巴尔通体遗传多样性的数据仍然缺乏。研究啮齿动物巴尔通体感染的流行病学特征，对预防和控制人类巴尔通体病具有重要意义。本研究在广西壮族自治区4个城市捕获鼠类，监测巴尔通体的流行情况。基于rrs基因共检出巴尔通体6种，其中3种为人畜共患巴尔通体，鼠体总流行率为11.5%（32/278）。三种人畜共患巴尔通体中优势种为三角巴尔通体（21/32,65.6%）。此外，对rrs、gltA和rpoB基因的系统发育和遗传分析表明，这些菌株在同一啮齿动物中被划分为不同的进化支，表明巴尔通体物种的多种遗传基因型共循环。本研究结果为进一步了解广西鼠类巴尔通体的流行情况和遗传多样性提供了依据，同时也为加强广西鼠类巴尔通体的监测工作提供了依据。

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引用次数: 0

Application of the Sm1-7-qPCR system for identifying S. mansoni DNA in experimentally infected mice Sm1-7-qPCR系统在实验感染小鼠曼氏梭菌DNA鉴定中的应用。

IF 2.1 3区医学 Q2 PARASITOLOGY

Acta tropica

Pub Date : 2025-01-01 DOI: 10.1016/j.actatropica.2024.107513

Eduardo Henrique Matos Pires, Natália Adriely Ribeiro da Silva Costa, Walter Lins Barbosa Júnior, Elainne Christine de Souza Gomes

Schistosomiasis presents a significant public health challenge, especially in regions with inadequate sanitation. Current diagnostic methods, including the Kato-Katz technique, often lack sensitivity in detecting low parasite loads, prompting the search for more precise alternatives. This study introduces the Sm1–7-qPCR system as a highly sensitive and specific diagnostic tool for identifying S. mansoni infections. The 15 female Swiss Webster mice were infected with S. mansoni cercariae, and the data were compared with those of the nested PCR assay and Kato-Katz technique.

The analytical sensitivity of the Sm1–7-qPCR system was tested using genomic DNA extracted from S. mansoni worms, which demonstrated excellent detection capability. For the analytical specificity, different parasites did not show amplification. The Sm1–7-qPCR system detected S. mansoni genomic DNA in 86.7 % of the stool samples from infected mice, surpassing the Kato-Katz method. The system showed high sensitivity and specificity, accurately quantifying parasite load in infected samples, showing promise in identifying patients with low parasite loads, and contributing to disease control efforts. In conclusion, the Sm1–7-qPCR system exhibited outstanding performance as a diagnostic tool for S. mansoni, surpassing traditional methods for detecting and quantifying parasite load. Further validation studies in low endemicity areas are recommended to enhance its integration into control and management strategies for S. mansoni infections.

血吸虫病是一项重大的公共卫生挑战，特别是在卫生设施不足的地区。目前的诊断方法，包括Kato-Katz技术，在检测低寄生虫载量时往往缺乏灵敏度，这促使人们寻找更精确的替代方法。本研究介绍了Sm1-7-qPCR系统作为一种高度敏感和特异性的诊断工具，用于鉴定曼氏链球菌感染。将15只雌性瑞士韦氏小鼠感染曼氏尾蚴，并与巢式PCR法和Kato-Katz技术进行比较。利用曼氏线虫基因组DNA对Sm1-7-qPCR系统的检测灵敏度进行了测试，结果表明Sm1-7-qPCR系统具有良好的检测能力。在分析特异性上，不同寄生虫均无扩增。Sm1-7-qPCR系统在感染小鼠粪便样本中检测到86.7%的曼氏链球菌基因组DNA，超过了Kato-Katz方法。该系统显示出高灵敏度和特异性，能够准确地定量感染样本中的寄生虫载量，有望识别低寄生虫载量的患者，并为疾病控制工作做出贡献。综上所述，Sm1-7-qPCR系统作为mansoni的诊断工具表现出优异的性能，超越了传统的寄生虫负荷检测和定量方法。建议在低流行地区进行进一步的验证研究，以加强其与曼氏链球菌感染控制和管理策略的结合。

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引用次数: 0

Global trends of schistosomiasis burden from 1990 to 2021 across 204 countries and territories: Findings from GBD 2021 study 1990 年至 2021 年 204 个国家和地区血吸虫病负担的全球趋势：GBD 2021 研究结果。

IF 2.1 3区医学 Q2 PARASITOLOGY

Acta tropica

Pub Date : 2025-01-01 DOI: 10.1016/j.actatropica.2024.107504

Qin Li , Yin-Long Li , Su-Ying Guo , Shi-Zhen Li , Qiang Wang , Wei-Na Lin , Li-Juan Zhang , Shi-Zhu Li , Xiao-Nong Zhou , Jing Xu

Introduction

The WHO aims to eliminate schistosomiasis as a public health problem by 2030. Based on the Global Burden of Disease 2021 (GBD 2021), this study assesses the global distribution of schistosomiasis burden to guide policy and resource allocation.

Methods

Schistosomiasis burden and social-demographic indexes (SDIs) data were extracted from GBD 2021 study. Smoothing spline models were used to examine the relationship between age-standardized prevalence rates (ASPR), DALY rates, mortality rates (ASMR), and SDI. Future burden predictions till 2030 were made using a Bayesian age-period-cohort model. Predictions and their 95 % certainty intervals were used to determine whether the region can meet the target by 2030.

Results

Globally, the burden of schistosomiasis was substantial (prevalence: 151.38 million; DALYs: 1,746,333.31; deaths: 12,857.57) in 2021. Africa accounted for most burden (Prevalence: 84.25 %; DALYs: 87.92 %; Deaths: 87.28 %). Among all age groups, individuals aged 15 to 24 years old bear the heaviest burden in 2021. The ASPR, Age-standardized DALY rate and ASMR were inversely correlated to the SDIs across different super regions (r = -0.72, P < 0.00; r = -0.71, P < 0.00; r = -0.71, P < 0.00) and countries and territories (r = 0.02, P = 0.85; r = -0.48, P < 0.00; r = -0.72, P < 0.00). According to model results, the burden of schistosomiasis in most regions will continue to decline in the future, while it in regions with high-income presented slightly rising.

Conclusions

Despite significant progress, further effects are needed to achieve the 2030 goal across the world. Additionally, the rising ASR of DALY of schistosomiasis in regions with high-income warrants attentions.

导言：世界卫生组织的目标是到 2030 年消除血吸虫病这一公共卫生问题。根据《2021 年全球疾病负担》（GBD 2021），本研究评估了血吸虫病负担的全球分布情况，以指导政策制定和资源分配：方法：从 GBD 2021 研究中提取血吸虫病负担和社会人口指数（SDIs）数据。使用平滑样条模型来检验年龄标准化流行率（ASPR）、残疾调整寿命年率（DALY）、死亡率（ASMR）和社会人口指数（SDI）之间的关系。使用贝叶斯年龄-时期-队列模型对 2030 年前的未来负担进行了预测。预测结果及其 95% 的确定性区间用于确定该地区是否能在 2030 年前实现目标：从全球来看，2021 年血吸虫病造成的负担是巨大的（流行率：1.5138 亿；残疾调整寿命年数：1746333.31；死亡人数：12857.57）。非洲的负担最重（患病率：84.25%；残疾调整寿命年数：87.92%；死亡人数：87.28%）。在所有年龄组中，15 至 24 岁的人在 2021 年承受的负担最重。在不同的超级地区，ASPR、年龄标准化 DALY 率和 ASMR 与 SDIs 呈反向关系（r = -0.72，P < 0.00；r = -0.71，P 结论）：尽管取得了重大进展，但要在全球范围内实现 2030 年的目标，还需要进一步的努力。此外，高收入地区血吸虫病残疾调整寿命年数的增加也值得关注。

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引用次数: 0

Updated global distribution of Plasmodium vivax circumsporozoite protein variants and their correlation with vector susceptibility: A systematic review and meta-analysis

IF 2.1 3区医学 Q2 PARASITOLOGY

Acta tropica

Pub Date : 2025-01-01 DOI: 10.1016/j.actatropica.2024.107508

Marrara P. Sampaio , Marcelo Cerilo-Filho , Yasmin de A․G․do Amaral , Maria Naely G. Almeida , Rayanne I. Correa , Dulce J.V. Fernando , Nathália F. Reis , Leonardo A. Miceli , José R.S. Silva , Luciane M. Storti-Melo , Andréa R.S. Baptista , Ricardo L.D. Machado

The global distribution of Plasmodium vivax Circumsporozoite Protein variants (PvCSP), VK210, VK247, and P. vivax-like, plays a crucial role in malaria transmission and vaccine development. This systematic review and meta-analysis assessed the prevalence of these variants in humans and their association with Anopheles species worldwide. Following PRISMA statement, 94 studies were selected from 26,888 found. Of these, 65 focused on the distribution of PvCSP variants in humans, and 29 on Anopheles species, which were also included in a meta-analysis of vector susceptibility. Fixed and random effects, as well as heterogeneity, were analyzed, with results presented in maps, graphics and tables. VK210 was the most prevalent variant globally, in humans and vectors. The meta-analysis revealed that 22 of the 94 Anopheles species analyzed (23.4 %) were susceptible to pure or mixed infections with PvCSP variants. All 22 species (100 %) were susceptible to mono-infections with VK210, while 14 species (63.6 %) showed susceptibility to VK247 mono-infections, and six species (27.3 %) to mixed infections. The P. vivax-like variant, although rare, has been identified in humans from Brazil and Guiana, as well as in the vectors Anopheles oswaldoi and Anopheles daeneorum exclusively in Brazil. These data highlight the importance of vector competence and environmental factors in shaping regional PvCSP variant distribution, with implications for malaria control and vaccine development strategies.

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引用次数: 0

Schistosomiasis status and health impact in preschool-aged children in hard-to-reach areas and populations of Homa Bay County, Kenya 肯尼亚霍马贝县难以到达地区和人口的学龄前儿童血吸虫病状况和健康影响

IF 2.1 3区医学 Q2 PARASITOLOGY

Acta tropica

Pub Date : 2025-01-01 DOI: 10.1016/j.actatropica.2024.107511

Phyllis Munyiva Isaiah , Bryan Nyawanda , Collins Okoyo , Joseph Otieno Oloo , Peter Steinmann

Pediatric schistosomiasis in hard-to-reach communities is poorly understood, hampering tailored interventions. This study investigated the prevalence, intensity, health impact, and risk factors for schistosomiasis in preschool-aged children (PSAC) residing in hard-to-reach areas and populations of Homa Bay County, Kenya.

A cross-sectional study was conducted among 476 PSAC aged 2–5 years across 6 islands in Lake Victoria, Homa Bay County, Kenya. Kato-Katz and urine filtration techniques diagnosed Schistosoma mansoni and S. haematobium infections respectively. Fecal occult blood (FOB) was tested to assess morbidity, and questionnaires captured sociodemographic and household water, sanitation, and hygiene data. Logistic regression models explored risk factors.

The overall prevalence of S. mansoni was 26.0 %, varying considerably between islands; Ringiti had the highest prevalence (62.1 %), while Sukru had the lowest (7.7 %). No S. haematobium infections were diagnosed. Light infections were most common (15.4 %), followed by moderate (8.5 %) and heavy infections (2.2 %). Significantly increased odds for infection were observed in children aged four (aOR = 4.4, 95 % CI: 1.7–11.2) and five years (aOR = 5.6, 95 % CI: 2.2–14.5), in girls (aOR = 2.5, 95 % CI: 1.3–4.8), and in children living in Ringiti (aOR = 6.1, 95 % CI: 1.8–15.0). We noted a strong association between S. mansoni infection and FOB (aOR= 3.3, 95 % CI: 1.6–7.0).

We found a high burden of schistosomiasis among PSAC in hard-to-reach communities of Homa Bay County, emphasizing the urgent need to include them in control programs. FOB could be a promising indicator for assessing schistosomiasis-related morbidity in this age group.

人们对难以到达的社区的儿童血吸虫病了解甚少，妨碍了有针对性的干预措施。本研究调查了居住在肯尼亚Homa Bay县难以到达地区和人群的学龄前儿童（PSAC）血吸虫病的患病率、强度、健康影响和危险因素。一项横断面研究对476名年龄在2-5岁的PSAC进行了跨越6个岛屿在维多利亚湖，霍马湾县，肯尼亚。加藤-卡茨和尿液过滤技术分别诊断为曼氏血吸虫和血链球菌感染。测试粪便隐血（FOB）以评估发病率，调查问卷收集社会人口和家庭用水、环境卫生和个人卫生数据。Logistic回归模型探讨了风险因素。mansoni的总流行率为26.0%，岛屿间差异较大；Ringiti患病率最高（62.1%），Sukru患病率最低（7.7%）。未诊断出血葡萄球菌感染。轻度感染最常见（15.4%），其次是中度感染（8.5%）和重度感染（2.2%）。在4岁儿童（aOR = 4.4,95%CI: 1.7 - 11.2）和5岁儿童（aOR = 5.6,95%CI: 2.2 - 14.5）、女童（aOR = 2.5,95%CI: 1.3 - 4.8）和居住在Ringiti的儿童（aOR = 6.1,95%CI: 1.8 - 15.0）中，感染的几率显著增加。我们注意到曼氏链球菌感染与FOB有很强的相关性（aOR= 3.3, 95%CI: 1.6 - 7.0）。我们发现，在Homa Bay县难以到达的社区中，PSAC的血吸虫病负担很高，强调迫切需要将其纳入控制规划。FOB可能是评估该年龄组血吸虫病相关发病率的一个有希望的指标。

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引用次数: 0