Pub Date : 2025-03-01DOI: 10.1016/j.ijid.2025.107809
Helen J. Mayfield , Ramona Muttucumaru , Benn Sartorius , Sarah Sheridan , Selina Ward , Beatris Mario Martin , Shannon M. Hedtke , Robert Thomsen , Satupaitea Viali , Glen Fatupaito , Colleen L. Lau , Patricia M. Graves
Objectives
Contrasting evidence is emerging on the long-term effectiveness of triple-drug therapy for elimination of lymphatic filariasis (LF) in the Pacific region. We evaluated the effectiveness of ivermectin, diethylcarbamazine and albendazole (IDA) for sustained clearance of microfilariae (Mf) in Samoa.
Methods
We enrolled two cohorts of Mf-positive participants. Cohort A were Mf-positive participants from 2018, who received directly observed triple-drug therapy in 2019 and were retested and retreated in 2023 and 2024. Cohort B were Mf-positive and treated in 2023 and retested in 2024. Participants were tested for LF antigen and Mf.
Results
In Cohort A, eight of the 14 participants from 2018/2019 were recruited in 2023; six were Mf-positive. In 2024, six participants were retested, and two were Mf-positive. Cohort B included eight participants, and two remained Mf-positive in 2024. Mf prevalence in 2023 for Cohort A (71.4%, 95% CI 29.0%-96.3%) was significantly higher than among their household members (12.0%, 95% CI 2.5%-31.2%).
Conclusion
One or two doses of directly observed IDA was not sufficient for sustained clearance of Wuchereria bancrofti Mf in Samoa. The high Mf prevalence in treated individuals compared to household members suggests recrudescence rather than reinfection.
{"title":"Recurrence of microfilaraemia after triple-drug therapy for lymphatic filariasis in Samoa: Recrudescence or reinfection?","authors":"Helen J. Mayfield , Ramona Muttucumaru , Benn Sartorius , Sarah Sheridan , Selina Ward , Beatris Mario Martin , Shannon M. Hedtke , Robert Thomsen , Satupaitea Viali , Glen Fatupaito , Colleen L. Lau , Patricia M. Graves","doi":"10.1016/j.ijid.2025.107809","DOIUrl":"10.1016/j.ijid.2025.107809","url":null,"abstract":"<div><h3>Objectives</h3><div>Contrasting evidence is emerging on the long-term effectiveness of triple-drug therapy for elimination of lymphatic filariasis (LF) in the Pacific region. We evaluated the effectiveness of ivermectin, diethylcarbamazine and albendazole (IDA) for sustained clearance of microfilariae (Mf) in Samoa.</div></div><div><h3>Methods</h3><div>We enrolled two cohorts of Mf-positive participants. Cohort A were Mf-positive participants from 2018, who received directly observed triple-drug therapy in 2019 and were retested and retreated in 2023 and 2024. Cohort B were Mf-positive and treated in 2023 and retested in 2024. Participants were tested for LF antigen and Mf.</div></div><div><h3>Results</h3><div>In Cohort A, eight of the 14 participants from 2018/2019 were recruited in 2023; six were Mf-positive. In 2024, six participants were retested, and two were Mf-positive. Cohort B included eight participants, and two remained Mf-positive in 2024. Mf prevalence in 2023 for Cohort A (71.4%, 95% CI 29.0%-96.3%) was significantly higher than among their household members (12.0%, 95% CI 2.5%-31.2%).</div></div><div><h3>Conclusion</h3><div>One or two doses of directly observed IDA was not sufficient for sustained clearance of <em>Wuchereria bancrofti</em> Mf in Samoa. The high Mf prevalence in treated individuals compared to household members suggests recrudescence rather than reinfection.</div></div>","PeriodicalId":14006,"journal":{"name":"International Journal of Infectious Diseases","volume":"152 ","pages":"Article 107809"},"PeriodicalIF":4.8,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143074409","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-01DOI: 10.1016/j.ijid.2025.107827
Mr Cedric Marsboom
Avia-GIS R&D team has an extensive expertise in the spatial modeling of vector-borne diseases (VBDs) to address critical concerns regarding the epidemiology and control of VBDs. Our work focuses on dissecting the complex interactions between vectors, hosts, and the environmental conditions that facilitate disease transmission. Through the integration of machine learning techniques, our endeavors to predict not only the presence and activity of disease vectors but also the potential for disease outbreaks and their impact on populations in a one health context.
Central to our approach are three questions concerning the vector: (1) Where is the vector present? (2) When will the vector be active? and (3) How many vectors will be active at any given time? These inquiries are crucial for understanding the spatial and temporal dynamics of vector populations, which in turn influence the transmission of vector-borne diseases. Answering these questions, aids in identifying areas and times of high transmission risk, thereby enabling more effective vector control strategies and disease prevention measures.
Parallel to the vector-focused analysis, similar questions need to be answered from the disease perspective: (1) Where can the disease occur? (2) When will there be an outbreak? and (3) How much of he population will be affected? This aspect of our work is aimed at predicting the geographical spread and timing of disease outbreaks, as well as estimating the potential number of cases. Such predictions are vital for public health planning and response, as they help in allocating resources efficiently and implementing timely interventions to mitigate the impact of outbreaks.
The integration of insights from both the vector and disease aspects forms the foundation of an early warning system. Such a system combines data on vector presence and activity with information on environmental and climatic conditions, host population, and historical disease incidence to forecast where and when outbreaks are likely to occur, and how severe they may be. Machine learning techniques play a pivotal role in this process, enabling the analysis of large datasets and the identification of patterns that may not be apparent through traditional epidemiological methods.
{"title":"Spatial modelling of vector-borne diseases: Where? When? How many?","authors":"Mr Cedric Marsboom","doi":"10.1016/j.ijid.2025.107827","DOIUrl":"10.1016/j.ijid.2025.107827","url":null,"abstract":"<div><div>Avia-GIS R&D team has an extensive expertise in the spatial modeling of vector-borne diseases (VBDs) to address critical concerns regarding the epidemiology and control of VBDs. Our work focuses on dissecting the complex interactions between vectors, hosts, and the environmental conditions that facilitate disease transmission. Through the integration of machine learning techniques, our endeavors to predict not only the presence and activity of disease vectors but also the potential for disease outbreaks and their impact on populations in a one health context.</div><div>Central to our approach are three questions concerning the vector: (1) Where is the vector present? (2) When will the vector be active? and (3) How many vectors will be active at any given time? These inquiries are crucial for understanding the spatial and temporal dynamics of vector populations, which in turn influence the transmission of vector-borne diseases. Answering these questions, aids in identifying areas and times of high transmission risk, thereby enabling more effective vector control strategies and disease prevention measures.</div><div>Parallel to the vector-focused analysis, similar questions need to be answered from the disease perspective: (1) Where can the disease occur? (2) When will there be an outbreak? and (3) How much of he population will be affected? This aspect of our work is aimed at predicting the geographical spread and timing of disease outbreaks, as well as estimating the potential number of cases. Such predictions are vital for public health planning and response, as they help in allocating resources efficiently and implementing timely interventions to mitigate the impact of outbreaks.</div><div>The integration of insights from both the vector and disease aspects forms the foundation of an early warning system. Such a system combines data on vector presence and activity with information on environmental and climatic conditions, host population, and historical disease incidence to forecast where and when outbreaks are likely to occur, and how severe they may be. Machine learning techniques play a pivotal role in this process, enabling the analysis of large datasets and the identification of patterns that may not be apparent through traditional epidemiological methods.</div></div>","PeriodicalId":14006,"journal":{"name":"International Journal of Infectious Diseases","volume":"152 ","pages":"Article 107827"},"PeriodicalIF":4.8,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143519740","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-01DOI: 10.1016/j.ijid.2025.107861
Craig R Cohen
Chlamydia trachomatis remains the most common bacterial sexually transmitted infection globally. Recent Phase 1 trials of the C. trachomatis vaccine candidate CTH522 in both women and men have shown that the adjuvanted and non-adjuvanted formulations are safe and elicit systemic (IgG) and mucosal (IgA) antibodies, as well as vaccine-specific cell-mediated immunity. In advance of a standard Phase 2 randomized controlled trial to determine the vaccine's efficacy, this perspective advocates for using a carefully and ethically designed human challenge model as an innovative approach to assess a vaccine's ability to prevent infection and its impact on tubal immunopathogenesis in breakthrough infections. Such models could accelerate vaccine development by providing critical insights, making it essential for stakeholders to consider this approach and expedite the long-awaited chlamydia vaccine.
{"title":"Innovative Approach for the Clinical Development of a Chlamydia trachomatis Vaccine Through a Human-Challenge Model in Women.","authors":"Craig R Cohen","doi":"10.1016/j.ijid.2025.107861","DOIUrl":"https://doi.org/10.1016/j.ijid.2025.107861","url":null,"abstract":"<p><p>Chlamydia trachomatis remains the most common bacterial sexually transmitted infection globally. Recent Phase 1 trials of the C. trachomatis vaccine candidate CTH522 in both women and men have shown that the adjuvanted and non-adjuvanted formulations are safe and elicit systemic (IgG) and mucosal (IgA) antibodies, as well as vaccine-specific cell-mediated immunity. In advance of a standard Phase 2 randomized controlled trial to determine the vaccine's efficacy, this perspective advocates for using a carefully and ethically designed human challenge model as an innovative approach to assess a vaccine's ability to prevent infection and its impact on tubal immunopathogenesis in breakthrough infections. Such models could accelerate vaccine development by providing critical insights, making it essential for stakeholders to consider this approach and expedite the long-awaited chlamydia vaccine.</p>","PeriodicalId":14006,"journal":{"name":"International Journal of Infectious Diseases","volume":" ","pages":"107861"},"PeriodicalIF":4.8,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143541984","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-01DOI: 10.1016/j.ijid.2024.107445
Dr Christin Schmidt , Dr Florian Hastert , Dr Tim Beissert , Dr Ugur Sahin , Dr Mario Perkovic , Dr Barbara Schnierle
Introduction
The human pathogenic chikungunya virus (CHIKV) has caused outbreaks in over 100 countries worldwide and is raising public health concern. Further spread by mosquito vectors due to globalization and climate change is expected. The symptoms of a CHIKV infection include fever, headache, myalgia, arthritis, and joint pain. Although the mortality rate is rather low, infections can result in debilitating arthralgia that can become chronic. Accordingly, we aim to explore potential CHIKV vaccine candidates.
Methods
Our first-generation CHIKV vaccine candidate was based on trans-amplifying RNA (taRNA), consisting of two RNAs: a non-replicating mRNA encoding for the CHIKV nonstructural proteins, forming the replicase complex and a trans-replicon (TR) RNA encoding the CHIKV envelope proteins. The TR-RNA is efficiently amplified by the replicase in trans leading to a high antigen expression and potent immune responses. To optimize our taRNA platform, we now simplified the TR-RNA to the essential elements by removing the subgenomic promoter and redesigning the 5’ untranslated region. Additionally, we formulated our vaccine candidates with lipid nanoparticles and evaluated several modifications. Humoral and cellular immune responses were assessed after prime-boost immunization of mice.
Results
First, we could prove in vitro that the respective antigen can now be directly translated from the STR-RNA as from a normal mRNA. However, as the conserved sequence elements were preserved, the STR-RNA was efficiently amplified by the CHIKV replicase. Here, the usage of only the envelope proteins led to a high protein expression, whereas the addition of the capsid protein allowed the release of virus-like particles. The LNP formulation of our taRNA vaccine candidate led to a 4.3-fold greater antibody titer compared to intradermal vaccination in saline. In comparison to the previous TR-RNA, the STR-RNA induced a further 4-fold increase in antibody titers. Here, in contrast to our previous results, all mice developed potent neutralizing antibody responses. Importantly, we could drastically reduce the taRNA dose. Neutralizing antibodies could be induced with as little as 1 ng STR-RNA and 5 ng STR-RNA were sufficient to protect all mice from a CHIKV challenge infection.
Discussion
The CHIKV is of increasing public health concern after its rapid global spread. In comparison to mRNA vaccines, the platform of taRNA allows to significantly reduce the required RNA doses for protective immunity. Nevertheless, the potential of taRNA as vaccine in humans still needs to be established in clinical trials.
Conclusion
In conclusion, taRNA represents a promising safe and efficient vaccination strategy for emerging infectious diseases.
{"title":"An optimized chikungunya virus trans-amplifying RNA vaccine candidate induces potent immune responses with only 1 ng of antigen encoding RNA","authors":"Dr Christin Schmidt , Dr Florian Hastert , Dr Tim Beissert , Dr Ugur Sahin , Dr Mario Perkovic , Dr Barbara Schnierle","doi":"10.1016/j.ijid.2024.107445","DOIUrl":"10.1016/j.ijid.2024.107445","url":null,"abstract":"<div><h3>Introduction</h3><div>The human pathogenic chikungunya virus (CHIKV) has caused outbreaks in over 100 countries worldwide and is raising public health concern. Further spread by mosquito vectors due to globalization and climate change is expected. The symptoms of a CHIKV infection include fever, headache, myalgia, arthritis, and joint pain. Although the mortality rate is rather low, infections can result in debilitating arthralgia that can become chronic. Accordingly, we aim to explore potential CHIKV vaccine candidates.</div></div><div><h3>Methods</h3><div>Our first-generation CHIKV vaccine candidate was based on trans-amplifying RNA (taRNA), consisting of two RNAs: a non-replicating mRNA encoding for the CHIKV nonstructural proteins, forming the replicase complex and a trans-replicon (TR) RNA encoding the CHIKV envelope proteins. The TR-RNA is efficiently amplified by the replicase in trans leading to a high antigen expression and potent immune responses. To optimize our taRNA platform, we now simplified the TR-RNA to the essential elements by removing the subgenomic promoter and redesigning the 5’ untranslated region. Additionally, we formulated our vaccine candidates with lipid nanoparticles and evaluated several modifications. Humoral and cellular immune responses were assessed after prime-boost immunization of mice.</div></div><div><h3>Results</h3><div>First, we could prove in vitro that the respective antigen can now be directly translated from the STR-RNA as from a normal mRNA. However, as the conserved sequence elements were preserved, the STR-RNA was efficiently amplified by the CHIKV replicase. Here, the usage of only the envelope proteins led to a high protein expression, whereas the addition of the capsid protein allowed the release of virus-like particles. The LNP formulation of our taRNA vaccine candidate led to a 4.3-fold greater antibody titer compared to intradermal vaccination in saline. In comparison to the previous TR-RNA, the STR-RNA induced a further 4-fold increase in antibody titers. Here, in contrast to our previous results, all mice developed potent neutralizing antibody responses. Importantly, we could drastically reduce the taRNA dose. Neutralizing antibodies could be induced with as little as 1 ng STR-RNA and 5 ng STR-RNA were sufficient to protect all mice from a CHIKV challenge infection.</div></div><div><h3>Discussion</h3><div>The CHIKV is of increasing public health concern after its rapid global spread. In comparison to mRNA vaccines, the platform of taRNA allows to significantly reduce the required RNA doses for protective immunity. Nevertheless, the potential of taRNA as vaccine in humans still needs to be established in clinical trials.</div></div><div><h3>Conclusion</h3><div>In conclusion, taRNA represents a promising safe and efficient vaccination strategy for emerging infectious diseases.</div></div>","PeriodicalId":14006,"journal":{"name":"International Journal of Infectious Diseases","volume":"152 ","pages":"Article 107445"},"PeriodicalIF":4.8,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143520573","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-01DOI: 10.1016/j.ijid.2024.107390
Miss Susan Kavai , Dr Cecilia Mbae , Dr Sylvia Omulo , Prof Julius Oyugi , Prof Samuel Kariuki
Introduction
Whole genome sequencing (WGS) is an important tool for disease diagnostics and identification of circulating multi-drug resistant (MDR) genotypes of enteric pathogens globally. In typhoid-endemic regions, WGS of Salmonella Typhi (S. Typhi) has identified haplotype 58 (H58) as one of the dominant MDR haplogroups. This case-control study reports on antimicrobial resistance (AMR) genes and genotypic diversity of S. Typhi from sick and asymptomatic children in Mukuru and Kibera informal settlements in Nairobi County.
Methods
From 2013 to 2018, children ≤ 16 years presenting to 4 health facilities in Nairobi County were recruited if they had a fever; ≥380C with or without diarrhea. Asymptomatic individuals (controls) who reported to the facilities for vaccinations and with non-typhoid-related symptoms were also recruited. Both groups provided stool samples that were subjected to culture and antimicrobial susceptibility testing for phenotypic analysis of AMR. S. Typhi isolates that showed resistance to ampicillin, co-trimoxazole, and chloramphenicol were considered as MDR and subjected to WGS. Deoxyribonucleic acid (DNA) of 90 S. Typhi isolates (44 from sick and 46 from asymptomatic individuals) was extracted for WGS. Sequencing was done using the Illumina Nextseq2000 platform. The generated raw reads were de novo assembled and pathogen-watch was used for analysis.
Results
Of the sequenced isolates, 60(69%) were confirmed to be S. Typhi. All of the S. Typhi belonged to the sequence Type 1 and genotype 4.3.1 (Haplotype 58). Out of the 60 S. Typhi strains 40(67%) were found to have plasmids, out of which 38(95%) had the IncHI1A/IncHI1B (R27) plasmids. The distribution of S. Typhi in sick and asymptomatic individuals was almost equal at 31(51%) and 30(49%). The 60 S. Typhi isolates were observed to have AMR determinants of 6 antibiotics with ampicillin (bla TEM-1D) as the most common, observed in 59 (98%) of the isolates. Point mutations conferring reduced susceptibility to quinolones were detected in 42 (70%) of S. Typhi isolates, 14(33%) gyrA_S83Y, and 28/42 (67%) gyrB_S464F.
Discussion
This study reports all MDR S. Typhi sequenced to belong to sequence Type 1. Genotype 4.3.1 (H58) was observed as the most dominant S. Typhi genotype among the symptomatic and asymptomatic individuals. Haplotype 58 is responsible for the spread of MDR phenotypes that carry on IncHI1 plasmids.
Conclusion
Circulation of H58 S. Typhi genotypes in Mukuru and Kibera informal settlements especially among asymptomatic individuals reiterates the need for mass vaccination as a control and prevention measure of Typhoid fever in urban informal settlements in Kenya.
{"title":"Genotypic diversity and antimicrobial resistance determinants in Salmonella Typhi isolated from children living in informal settlements in Nairobi, Kenya","authors":"Miss Susan Kavai , Dr Cecilia Mbae , Dr Sylvia Omulo , Prof Julius Oyugi , Prof Samuel Kariuki","doi":"10.1016/j.ijid.2024.107390","DOIUrl":"10.1016/j.ijid.2024.107390","url":null,"abstract":"<div><h3>Introduction</h3><div>Whole genome sequencing (WGS) is an important tool for disease diagnostics and identification of circulating multi-drug resistant (MDR) genotypes of enteric pathogens globally. In typhoid-endemic regions, WGS of Salmonella Typhi (S. Typhi) has identified haplotype 58 (H58) as one of the dominant MDR haplogroups. This case-control study reports on antimicrobial resistance (AMR) genes and genotypic diversity of S. Typhi from sick and asymptomatic children in Mukuru and Kibera informal settlements in Nairobi County.</div></div><div><h3>Methods</h3><div>From 2013 to 2018, children ≤ 16 years presenting to 4 health facilities in Nairobi County were recruited if they had a fever; ≥380C with or without diarrhea. Asymptomatic individuals (controls) who reported to the facilities for vaccinations and with non-typhoid-related symptoms were also recruited. Both groups provided stool samples that were subjected to culture and antimicrobial susceptibility testing for phenotypic analysis of AMR. S. Typhi isolates that showed resistance to ampicillin, co-trimoxazole, and chloramphenicol were considered as MDR and subjected to WGS. Deoxyribonucleic acid (DNA) of 90 S. Typhi isolates (44 from sick and 46 from asymptomatic individuals) was extracted for WGS. Sequencing was done using the Illumina Nextseq2000 platform. The generated raw reads were de novo assembled and pathogen-watch was used for analysis.</div></div><div><h3>Results</h3><div>Of the sequenced isolates, 60(69%) were confirmed to be S. Typhi. All of the S. Typhi belonged to the sequence Type 1 and genotype 4.3.1 (Haplotype 58). Out of the 60 S. Typhi strains 40(67%) were found to have plasmids, out of which 38(95%) had the IncHI1A/IncHI1B (R27) plasmids. The distribution of S. Typhi in sick and asymptomatic individuals was almost equal at 31(51%) and 30(49%). The 60 S. Typhi isolates were observed to have AMR determinants of 6 antibiotics with ampicillin (bla TEM-1D) as the most common, observed in 59 (98%) of the isolates. Point mutations conferring reduced susceptibility to quinolones were detected in 42 (70%) of S. Typhi isolates, 14(33%) gyrA_S83Y, and 28/42 (67%) gyrB_S464F.</div></div><div><h3>Discussion</h3><div>This study reports all MDR S. Typhi sequenced to belong to sequence Type 1. Genotype 4.3.1 (H58) was observed as the most dominant S. Typhi genotype among the symptomatic and asymptomatic individuals. Haplotype 58 is responsible for the spread of MDR phenotypes that carry on IncHI1 plasmids.</div></div><div><h3>Conclusion</h3><div>Circulation of H58 S. Typhi genotypes in Mukuru and Kibera informal settlements especially among asymptomatic individuals reiterates the need for mass vaccination as a control and prevention measure of Typhoid fever in urban informal settlements in Kenya.</div></div>","PeriodicalId":14006,"journal":{"name":"International Journal of Infectious Diseases","volume":"152 ","pages":"Article 107390"},"PeriodicalIF":4.8,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143520314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-01DOI: 10.1016/j.ijid.2025.107818
Prof Justin Jang H Chu
<div><h3>Introduction</h3><div>Enterovirus D68 (EV-D68) can cause a spectrum of clinical symptoms from mild respiratory symptoms to severe disease which can lead to hospitalization and even fatality in the immunocompromised, the elderly, and young children. To date, there are no effective antiviral successfully developed for enterovirus infection and the current understanding on pathogenesis is limited, which has resulted in the persistent circulation and outbreaks across the globe.</div></div><div><h3>Methods</h3><div>An immunofluorescence-based phenotypic high-throughput antiviral screen was performed on both RD and H1299 cells, where 7,987 compounds across nine commercially-available drug libraries were screened for antiviral activity against Enterovirus D68 (EV-D68) strain US/KY/14-18953. Using a hit threshold of 50% inhibition and a toxicity threshold of nuclei count > 1000, 178 hits were identified. These hits were further filtered for novelty and potency, which led to the validation of 12 compounds. MARVAS DF01 was selected for subsequent experiments due to its high efficacy (IC50: 1.804 µM).</div></div><div><h3>Results</h3><div>MARVAS DF01 treatment of EV-D68 infected cells potently reduced viral protein and viral genomic RNA levels. The time-of-addition, time-of-removal, and entry bypass studies showed that MARVAS DF01 acts in the post-entry stages of EV-D68 replication, specifically between 4 to 6 hours post-infection. Transfecting a Nanoluciferase viral replicon containing a truncated viral 3D protein still resulted in a luminescence reduction, indicating that MARVAS DF01 affects viral protein translation. Following serial passaging of EV-D68 in the presence of MARVAS DF01, no resistant mutants were found after 18 passages, suggesting the target of MARVAS DF01 to be a host factor. To elucidate the specific target, siRNA knockdown of the four currently known host targets of MARVAS DF01 was performed, from which ULK1 and ULK2 were identified to be involved in EV-D68 replication. As these two proteins are canonically known as part of the autophagy pathway, MARVAS DF01 was investigated for its role in EV-D68-induced autophagy. Through western blot and immunofluorescence staining, the LC3-II/LC3-I ratio and number of LC3 puncta-positive cells increased upon EV-D68 infection, indicating autophagy induction in infected cells. MARVAS DF01 treatment reversed this phenomenon, suggesting its mechanism of inhibition to be through the autophagy pathway. Additionally, MARVAS DF01 is a broad-spectrum enterovirus antiviral, inhibiting the replication of representative viruses from Enterovirus A-D and Rhinovirus A. MARVAS DF01 also reduced EV-D68 replication primary human nasal epithelial cells.</div></div><div><h3>Discussion</h3><div>Our research has taken a leap into the identification of novel antivirals for EV-D68 and highlight the gap that necessitates further research to devise novel broad spectrum treatment approaches and modalities to thwart
{"title":"Antiviral Therapeutics Discovery for Enterovirus D68.","authors":"Prof Justin Jang H Chu","doi":"10.1016/j.ijid.2025.107818","DOIUrl":"10.1016/j.ijid.2025.107818","url":null,"abstract":"<div><h3>Introduction</h3><div>Enterovirus D68 (EV-D68) can cause a spectrum of clinical symptoms from mild respiratory symptoms to severe disease which can lead to hospitalization and even fatality in the immunocompromised, the elderly, and young children. To date, there are no effective antiviral successfully developed for enterovirus infection and the current understanding on pathogenesis is limited, which has resulted in the persistent circulation and outbreaks across the globe.</div></div><div><h3>Methods</h3><div>An immunofluorescence-based phenotypic high-throughput antiviral screen was performed on both RD and H1299 cells, where 7,987 compounds across nine commercially-available drug libraries were screened for antiviral activity against Enterovirus D68 (EV-D68) strain US/KY/14-18953. Using a hit threshold of 50% inhibition and a toxicity threshold of nuclei count > 1000, 178 hits were identified. These hits were further filtered for novelty and potency, which led to the validation of 12 compounds. MARVAS DF01 was selected for subsequent experiments due to its high efficacy (IC50: 1.804 µM).</div></div><div><h3>Results</h3><div>MARVAS DF01 treatment of EV-D68 infected cells potently reduced viral protein and viral genomic RNA levels. The time-of-addition, time-of-removal, and entry bypass studies showed that MARVAS DF01 acts in the post-entry stages of EV-D68 replication, specifically between 4 to 6 hours post-infection. Transfecting a Nanoluciferase viral replicon containing a truncated viral 3D protein still resulted in a luminescence reduction, indicating that MARVAS DF01 affects viral protein translation. Following serial passaging of EV-D68 in the presence of MARVAS DF01, no resistant mutants were found after 18 passages, suggesting the target of MARVAS DF01 to be a host factor. To elucidate the specific target, siRNA knockdown of the four currently known host targets of MARVAS DF01 was performed, from which ULK1 and ULK2 were identified to be involved in EV-D68 replication. As these two proteins are canonically known as part of the autophagy pathway, MARVAS DF01 was investigated for its role in EV-D68-induced autophagy. Through western blot and immunofluorescence staining, the LC3-II/LC3-I ratio and number of LC3 puncta-positive cells increased upon EV-D68 infection, indicating autophagy induction in infected cells. MARVAS DF01 treatment reversed this phenomenon, suggesting its mechanism of inhibition to be through the autophagy pathway. Additionally, MARVAS DF01 is a broad-spectrum enterovirus antiviral, inhibiting the replication of representative viruses from Enterovirus A-D and Rhinovirus A. MARVAS DF01 also reduced EV-D68 replication primary human nasal epithelial cells.</div></div><div><h3>Discussion</h3><div>Our research has taken a leap into the identification of novel antivirals for EV-D68 and highlight the gap that necessitates further research to devise novel broad spectrum treatment approaches and modalities to thwart","PeriodicalId":14006,"journal":{"name":"International Journal of Infectious Diseases","volume":"152 ","pages":"Article 107818"},"PeriodicalIF":4.8,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143520464","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-01DOI: 10.1016/j.ijid.2024.107433
Miss Tebello Kolobe
<div><h3>Background</h3><div>Cholera remains a public health threat in Zambia, particularly in hotspot areas like Chienge district in Luapula Province, where the most recent previous outbreak was recorded in 2017. An outbreak of cholera in Chienge was first suspected on May 02, 2023, and confirmed on May 08, 2023. By May 18, 2023, the district had recorded 47 cases. This study aimed to describe cases, identify the cause, and risk factors, and propose control measures.</div></div><div><h3>Methods</h3><div>An outbreak investigation followed by a 1: 2 matched case-control study were conducted. Suspected cases were individuals aged ≥2 years in the Lunchinda catchment area, presenting with acute watery diarrhoea with or without vomiting or signs of dehydration from April 28 to June 09, 2023. Confirmed cases involved isolation of vibrio cholerae O1 or 0139 from stool samples through culture. Cases and controls were matched by age and sex, with controls from the same household or neighbourhood. A structured questionnaire was used for interviews. The district is situated along the Luapula River and Lake Mweru, and has a total population of 189,893 that mainly depends on fishing as their main source of living. We conducted a descriptive analysis, calculated the case fatality rate (CFR), and applied Conditional logistic regression to determine odds ratios (OR) with 95% confidence interval in R.</div></div><div><h3>Results</h3><div>Between April 2018 to June 09, 2023, a total of 79 cases were recorded, with 24 lab-confirmed 01 (23 Inaba, 1 Ogawa) species and one community death (CFR: 1.27%). The overall attack rate was 3 cases per 1,000 population. Approximately 80% of the case patients clustered along the lake. All the cases were detected in the health facilities, and 92% exhibited severe dehydration. From 67 cases and 134 controls, none were vaccinated against cholera. The main water source was the lake (41%). The absence of hand washing stations (OR: 2.3, CI: 1.1-4.9), and chlorine before the outbreak (OR: 6.3, CI: 1.3-30.8) were significantly associated with cholera.</div></div><div><h3>Discussion</h3><div>The outbreak was linked to Vibrio cholerae O1, Inaba serotype. This community lacks safe water, sanitation, and hygiene (WASH) services as it is not under the administrative jurisdiction of the district. Both sexes were equally susceptible. Although the 1.2% fatality rate indicates effective management, it slightly surpasses WHO's threshold, possibly due to late health-seeking behaviours. Unknown vaccination status highlights gaps in coverage since the district conducted Cholera vaccination in the recent past. Risk factors like water source and treatment practices showed varied significance, emphasizing hand hygiene's crucial role.</div></div><div><h3>Conclusion</h3><div>The outbreak was primarily caused by Inaba serotype. CFR was slightly above the WHO recommendation. Unavailability of chlorine and hand washing stations were the significant risk fact
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Pub Date : 2025-03-01DOI: 10.1016/j.ijid.2024.107458
Dr Helen Callaby , Dr Janie Olver , Ms Kirsty Emery , Dr Kevin Richards , Dr Marian Killip , Dr Natalie Groves , Dr Jake Dunning , Professor Malcolm G Semple , Professor J Kenneth Baillie , Dr Tommy Rampling , Dr Catherine F Houlihan
Introduction
Monkeypox virus (MPXV), a DNA virus in the genus Orthopoxvirus, causes the clinical disease mpox. Human-to-human transmission occurs, primarily through contact with infectious lesions. The cycle threshold (Ct) value at which mpox virus can be isolated varies in the literature. Clarification of a Ct that correlates reliably with MPXV infectivity would have significant implications for infection control measures. Persistent viral shedding of mpox is widely reported but what is less well described is the duration of infectious MPXV from patient samples, using virus isolation as proxy.
Methods
This is a retrospective study using 169 longitudinal stored clinical isolates from 11 patients with clade II mpox. The samples were inoculated into African green monkey kidney (Vero E6) cells, termed passage 1 (P1). The P1 cultures were incubated and monitored for cytopathic effects (CPE). Cultures were sampled on day 0 and 7 and underwent virus inactivation, nucleic acid extraction and MPXV-specific PCR to support CPE observations. A decrease in mean MPXV Ct values from day 0 to 7 correlates to an increase in MPXV nucleic acid production, indicative of MPXV replication.
Results
The sampling frame for these patients ranged from the swab of an asymptomatic contact 13 days prior to the onset of symptoms, to 109 days post the onset of symptoms. 98 samples had a detectable Ct on MPXV PCR at day 0 (Ct range 20.1 to 39.7) and virus was able to be isolated from 46.9% of these samples (46/98). The cycle threshold at which virus was able to be isolated ranged from 22.3 to 37.7. Median MPXV Ct value for which virus could be isolated was 30.7. The longest duration from MPXV culture positivity from diagnosis was 109 days, from a throat swab with a Ct value of 35.9. The sample was from a 40-50 year old man with poorly controlled HIV CD4+ T-lymphocyte count 57 cells/mm3. HIV viral load 52,800 copies/ML) who presented with an ulcerating rash affecting limbs and a necrotic tongue lesion. The median time from mpox diagnosis to culture negative was 11.5 days (range 2 to 109).
Discussion
The duration of the infectious period of MPXV during clinical mpox is currently unclear with a paucity of robust longitudinal culture data, particularly from hospitalised patients. The median time of isolation of 11.5 days would fit within the known threshold but was far exceeded in a single immunocompromised patient at 109 days.
Conclusion
MPXV was isolated at higher Ct values than the previously reported, potentially removing the reassurance of lack of “infectiousness” in a patient with a rising Ct on PCR. Immunocompromised patients may be infectious with MPXV for longer than those with a competent immune system and these patients may require longer isolation.
{"title":"Monkeypox virus (MPXV) isolation from longitudinal samples of 11 patients to infer risk of onwards transmission","authors":"Dr Helen Callaby , Dr Janie Olver , Ms Kirsty Emery , Dr Kevin Richards , Dr Marian Killip , Dr Natalie Groves , Dr Jake Dunning , Professor Malcolm G Semple , Professor J Kenneth Baillie , Dr Tommy Rampling , Dr Catherine F Houlihan","doi":"10.1016/j.ijid.2024.107458","DOIUrl":"10.1016/j.ijid.2024.107458","url":null,"abstract":"<div><h3>Introduction</h3><div>Monkeypox virus (MPXV), a DNA virus in the genus Orthopoxvirus, causes the clinical disease mpox. Human-to-human transmission occurs, primarily through contact with infectious lesions. The cycle threshold (Ct) value at which mpox virus can be isolated varies in the literature. Clarification of a Ct that correlates reliably with MPXV infectivity would have significant implications for infection control measures. Persistent viral shedding of mpox is widely reported but what is less well described is the duration of infectious MPXV from patient samples, using virus isolation as proxy.</div></div><div><h3>Methods</h3><div>This is a retrospective study using 169 longitudinal stored clinical isolates from 11 patients with clade II mpox. The samples were inoculated into African green monkey kidney (Vero E6) cells, termed passage 1 (P1). The P1 cultures were incubated and monitored for cytopathic effects (CPE). Cultures were sampled on day 0 and 7 and underwent virus inactivation, nucleic acid extraction and MPXV-specific PCR to support CPE observations. A decrease in mean MPXV Ct values from day 0 to 7 correlates to an increase in MPXV nucleic acid production, indicative of MPXV replication.</div></div><div><h3>Results</h3><div>The sampling frame for these patients ranged from the swab of an asymptomatic contact 13 days prior to the onset of symptoms, to 109 days post the onset of symptoms. 98 samples had a detectable Ct on MPXV PCR at day 0 (Ct range 20.1 to 39.7) and virus was able to be isolated from 46.9% of these samples (46/98). The cycle threshold at which virus was able to be isolated ranged from 22.3 to 37.7. Median MPXV Ct value for which virus could be isolated was 30.7. The longest duration from MPXV culture positivity from diagnosis was 109 days, from a throat swab with a Ct value of 35.9. The sample was from a 40-50 year old man with poorly controlled HIV CD4+ T-lymphocyte count 57 cells/mm3. HIV viral load 52,800 copies/ML) who presented with an ulcerating rash affecting limbs and a necrotic tongue lesion. The median time from mpox diagnosis to culture negative was 11.5 days (range 2 to 109).</div></div><div><h3>Discussion</h3><div>The duration of the infectious period of MPXV during clinical mpox is currently unclear with a paucity of robust longitudinal culture data, particularly from hospitalised patients. The median time of isolation of 11.5 days would fit within the known threshold but was far exceeded in a single immunocompromised patient at 109 days.</div></div><div><h3>Conclusion</h3><div>MPXV was isolated at higher Ct values than the previously reported, potentially removing the reassurance of lack of “infectiousness” in a patient with a rising Ct on PCR. Immunocompromised patients may be infectious with MPXV for longer than those with a competent immune system and these patients may require longer isolation.</div></div>","PeriodicalId":14006,"journal":{"name":"International Journal of Infectious Diseases","volume":"152 ","pages":"Article 107458"},"PeriodicalIF":4.8,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143520683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2025-03-01DOI: 10.1016/j.ijid.2024.107416
Dr Igor Mokrousov , Prof. Tatiana Vinogradova , Dr. Marine Dogonadze , Dr. Natalia Zabolotnykh , Dr. Marina Dyakova , Dr. Dilyara Esmedlyaeva , Dr. Maria Vitovskaya , Dr Olga Rubtsova , Dr Sergei Chekrygin , Dr Anna Vyazovaya , Prof. Boris Ariel
<div><h3>Introduction</h3><div>The clinical manifestations of tuberculosis (TB) in humans represent a complex interaction between the causative agent, Mycobacterium tuberculosis, and the immune response of the human host. Using the murine model, we compared virulence of M. tuberculosis strains of the medically significant genotypes and evaluated the effectiveness of anti-TB therapy and inflammatory response in infected mice.</div></div><div><h3>Methods</h3><div>The C57BL/6 mice were infected with multidrug-resistant clinical M. tuberculosis strains of Beijing and LAM genotypes. Control groups were not treated and experimental groups received adequate treatment with moxifloxacin, linezolid, bedaquiline and perchlozone. After 2 and 5.5 months of therapy, groups of mice were euthanized and studied for bacterial load, histology, lung pathology, and biochemical markers of liver damage. Whole genome sequencing was performed on all bacterial isolates from the lungs of the treated mice and the obtained fastq files were analyzed using SAM-TB tool and Geneious package. This study was funded by Russian Science Foundation (grant 24-44-00004).</div></div><div><h3>Results</h3><div>The anti-TB therapy reduced the inflammation and tuberculous lung damage in all groups of mice, even in those infected with the most virulent strain Beijing 396. A significant effect of the anti-TB therapy was observed at both time-point for all groups. The highest effectiveness of the therapy was observed in mice infected with the least virulent strains Beijing 6691 and LAM 7074. At the same time, in 3 out of 4 groups of treated mice (except for those infected with the low-virulent strain LAM 7074), a slight increase in bacterial load was recorded by the end of the 5.5-month course of therapy. High-coverage WGS analysis showed that no mutations associated with resistance to the administered drugs emerged after 5.5 months of treatment. The study of non-specific inflammatory response revealed the differently severe acute inflammation in mice infected with different strains.</div></div><div><h3>Discussion</h3><div>The highest lung damage was observed in treated mice infected with Beijing 396, the lowest – in mice infected with low-virulent Beijing 6691 and LAM 7074. At the same time, the contrasting inflammatory responses were observed in mice infected with the LAM strains: the highest in those infected by highly-virulent strain 4542 (SIT266), the lowest – in mice infected with low-virulent strain 7074 (SIT252). Phylogenetically, these LAM strains belong to the genetically homogeneous LAM-RUS branch and their contrasting in vivo manifestation is noteworthy.</div></div><div><h3>Conclusions</h3><div>Some of the observed differences between studied strains distinguish between low-virulent and highly-virulent strains irrespective of the genotype. On the other hand, some other features were common for the strains of the same genotype either Beijing or LAM and might correlate with deeply roo
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Pub Date : 2025-03-01DOI: 10.1016/j.ijid.2024.107457
Ms Tshegofatso Mahlangu , Dr Tongai Maponga , Mr Martin Deijs , Prof Lia van der Hoek , Prof Gert van Zyl , Prof Davey Smith
<div><h3>Introduction and motivation</h3><div>Emerging and re-emerging viruses are a global health concern. Historically, such viruses have been identified through targeted approaches, which has been the gold standard in diagnosis. Unfortunately, these approaches are limited to known pathogens and thus inadequate for the monitoring of “unknown” viruses. Therefore, there is a need for a technology that can identify known, novel and unexpected viruses.</div><div>Virus discovery using copy deoxyribonucleic acid (cDNA) and amplified fragment length polymorphism (AFLP) (also called VIDISCA) is a metagenomics approach that non-specifically enriches for viral sequences and then uses next generation sequencing (NGS) for virus discovery. VIDISCA has been used for the discovery of a several previously unknown viruses, including human coronavirus (HCoV) NL63 and Ntwetwe virus.</div><div>VIDISCA has previously relied on Ion Torrent NGS, and we hypothesised that Oxford Nanopore Technology (ONT), which is easier to use, could be as effective as Ion Torrent sequencing. Therefore, we developed and validated VIDISCA with ONT and this compared to Ion Torrent NGS.</div></div><div><h3>Methodology</h3><div>A library made-up of different sample types was split into two identical libraries to sequence on the ONT and Ion Torrent platforms. The samples contained known viral pathogens which were blinded and treated as “unknown” samples for viral discovery. cDNA was synthesized with random primers from nucleic acid extracts that were depleted of rRNA complementary sequences. After second strand synthesis, DNA was digested with a restriction enzyme coupled with adaptor ligation, which served as priming sites for PCR enrichment. Templates are then sequenced, and output files were mapped against protein databases including human, mammal, insect, tick and avian virus sequences.</div></div><div><h3>Findings</h3><div>The two NGS platforms performed similarly in identifying the pathogens in the prepared library that contained Human Mastadenovirus (HAdV), Human Immunodeficiency virus (HIV), Hepatitis E virus (HEV), HCoV-NL63 and a virus free sample. Neither the ONT nor Ion Torrent platforms sequenced the HAdV. Both platforms also missed HEV in one sample. All other viruses were successfully identified by both platforms. Overall, ONT performed similarly to Ion Torrent.</div></div><div><h3>Conclusion and relevance</h3><div>VIDISCA performed on Ion Torrent and ONT sequencing platforms has displayed similar Results. ONT sequencing has the advantage of a more rapid turnaround and low sequencing footprint with a similar cost estimation.</div><div>Future plans include the testing of residual patient samples where some viruses are often undiagnosed (such as cerebrospinal fluid) as well as sentinel species (such as rats and shrews) as a part of pandemic preparedness and novel virus discovery. If necessary, additional work, such as genome primer walking, will be conducted for full-genome ch
{"title":"Investigating an agnostic metagenomic virus discovery tool and evaluating the performance of Ion Torrent versus Oxford Nanopore Technology sequencing","authors":"Ms Tshegofatso Mahlangu , Dr Tongai Maponga , Mr Martin Deijs , Prof Lia van der Hoek , Prof Gert van Zyl , Prof Davey Smith","doi":"10.1016/j.ijid.2024.107457","DOIUrl":"10.1016/j.ijid.2024.107457","url":null,"abstract":"<div><h3>Introduction and motivation</h3><div>Emerging and re-emerging viruses are a global health concern. Historically, such viruses have been identified through targeted approaches, which has been the gold standard in diagnosis. Unfortunately, these approaches are limited to known pathogens and thus inadequate for the monitoring of “unknown” viruses. Therefore, there is a need for a technology that can identify known, novel and unexpected viruses.</div><div>Virus discovery using copy deoxyribonucleic acid (cDNA) and amplified fragment length polymorphism (AFLP) (also called VIDISCA) is a metagenomics approach that non-specifically enriches for viral sequences and then uses next generation sequencing (NGS) for virus discovery. VIDISCA has been used for the discovery of a several previously unknown viruses, including human coronavirus (HCoV) NL63 and Ntwetwe virus.</div><div>VIDISCA has previously relied on Ion Torrent NGS, and we hypothesised that Oxford Nanopore Technology (ONT), which is easier to use, could be as effective as Ion Torrent sequencing. Therefore, we developed and validated VIDISCA with ONT and this compared to Ion Torrent NGS.</div></div><div><h3>Methodology</h3><div>A library made-up of different sample types was split into two identical libraries to sequence on the ONT and Ion Torrent platforms. The samples contained known viral pathogens which were blinded and treated as “unknown” samples for viral discovery. cDNA was synthesized with random primers from nucleic acid extracts that were depleted of rRNA complementary sequences. After second strand synthesis, DNA was digested with a restriction enzyme coupled with adaptor ligation, which served as priming sites for PCR enrichment. Templates are then sequenced, and output files were mapped against protein databases including human, mammal, insect, tick and avian virus sequences.</div></div><div><h3>Findings</h3><div>The two NGS platforms performed similarly in identifying the pathogens in the prepared library that contained Human Mastadenovirus (HAdV), Human Immunodeficiency virus (HIV), Hepatitis E virus (HEV), HCoV-NL63 and a virus free sample. Neither the ONT nor Ion Torrent platforms sequenced the HAdV. Both platforms also missed HEV in one sample. All other viruses were successfully identified by both platforms. Overall, ONT performed similarly to Ion Torrent.</div></div><div><h3>Conclusion and relevance</h3><div>VIDISCA performed on Ion Torrent and ONT sequencing platforms has displayed similar Results. ONT sequencing has the advantage of a more rapid turnaround and low sequencing footprint with a similar cost estimation.</div><div>Future plans include the testing of residual patient samples where some viruses are often undiagnosed (such as cerebrospinal fluid) as well as sentinel species (such as rats and shrews) as a part of pandemic preparedness and novel virus discovery. If necessary, additional work, such as genome primer walking, will be conducted for full-genome ch","PeriodicalId":14006,"journal":{"name":"International Journal of Infectious Diseases","volume":"152 ","pages":"Article 107457"},"PeriodicalIF":4.8,"publicationDate":"2025-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143520815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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