Frontiers in tropical diseases最新文献

{"title":"Retrospective on molecular assay design for detecting pan-orthopox viruses and prospective on mpox laboratory preparedness and readiness","authors":"Kenneth B Yeh, Michael D. Powers, Ami Patel, F. Parekh, A. Tseng, E. Bradford, Kyle Parker, Ricky Soong, G. Olinger, Illich Mombo","doi":"10.3389/fitd.2023.1221804","DOIUrl":"https://doi.org/10.3389/fitd.2023.1221804","url":null,"abstract":"The landscape of in vitro diagnostic (IVD) devices encompasses a broad range of tests that have been used to detect and diagnose pathogens, especially tropical diseases, for decades. The COVID-19 pandemic exemplified the greater need for bringing IVDs from the laboratory directly to the consumer, and recent outbreaks such as mpox, Sudan ebolavirus, and Marburg virus further reinforce this need. The increased emergence of tropical disease outbreaks requires more agile development, higher performance, and mass production of IVD devices. Furthermore, lessons learned in previous device developments can sometimes be used to accelerate new disease diagnostic applications. As an example, we describe one case history of an earlier pan-orthopox viral assay that detected smallpox variola and vaccinia strains, and also discerned related strains including mpox. This work established the foundation for the molecular detection of orthopox viruses, which could be mobilized to address public health needs once an emergency declaration was made that opened the FDA pathway for issuing an emergency use authorization for the use of these assays. Thus, the utilization of knowledge from earlier investments was shown to enhance preparedness and readiness. Here in this retrospective, we elaborate on the processes that enable this approach, including multi-disciplinary and multisectoral collaborations to accomplish a holistic, one health world.","PeriodicalId":73112,"journal":{"name":"Frontiers in tropical diseases","volume":"52 10","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41294124","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A major dengue epidemic in 2022 in Nepal: need of an efficient early-warning system","authors":"B. G. Dhoubhadel, Yumiko Hayashi, F. M. Domai, S. Bhattarai, K. Ariyoshi, B. Pandey","doi":"10.3389/fitd.2023.1217939","DOIUrl":"https://doi.org/10.3389/fitd.2023.1217939","url":null,"abstract":"Dengue has become a recurrent and growing threat to public health in Nepal. The epidemic in 2022 was the largest ever reported, with cases being reported in all of the country’s seven provinces and 77 districts. Despite the establishment of an early-warning and reporting system (EWARS) in 1997, the lack of clear criteria for alarm signals and outbreak definitions in national guidelines delayed the epidemic declaration in 2022, which resulted in an increased number of cases and fatalities. For this article, we analyzed national data from previous years, which demonstrate that an epidemic could have been declared early in July, and that that would have resulted in fewer cases and fatalities if clear criteria for outbreak declarations had also been put in place. We also reviewed the existing national guidelines for dengue prevention and control, and propose recommendations to improve their implementation, particularly with regard to vector control measures. This article also highlights the need for a coordinated effort between multisector stakeholders, strengthened disease surveillance systems, and the establishment of predefined alarm signals and epidemic declaration criteria so that future epidemics are identified in a timely manner. The early outbreak warning system can potentially prevent future large outbreaks and minimize their negative impacts on the country’s health systems and economy.","PeriodicalId":73112,"journal":{"name":"Frontiers in tropical diseases","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44320090","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Malaria mitochondrial diagnosis: challenges and pitfalls","authors":"Gabriel Luíz Costa, D. A. Alvarenga, Gabriela Maíra Pereira de Assis, A. Aguiar, Jaime Louzada, D. Pereira, A. Pina-Costa, Z. Hirano, S. B. Moreira, A. Pissinatti, P. Brasil, C. Daniel-Ribeiro, T. Sousa, C. F. Alves de Brito","doi":"10.3389/fitd.2023.1204195","DOIUrl":"https://doi.org/10.3389/fitd.2023.1204195","url":null,"abstract":"High-copy genomic sequences could be used as PCR targets for the detection of Plasmodium infections, providing increased sensitivity over single- or low-copy genes. Mitochondrial genomes of malaria parasites are present in multiple copies in a single mitochondrion, and each parasite has many mitochondria. Here, we describe the development of seven species-specific qPCR assays for the diagnosis of Plasmodium vivax and Plasmodium falciparum, targeting coding and non-coding mitochondrial genomic regions.The optimization of the qPCR protocols involved a gradient of annealing temperatures and concentrations of primers and probes, as well as the inclusion of PCR additives/enhancers [e.g., dimethyl sulfoxide (DMSO), glycerol, bovine serum albumin (BSA)] to improve the specificity of qPCR amplification.Non-specific amplification of other Plasmodium species and of human targets was observed in different levels for all assays. Regardless of the late Cq values for most non-specific amplifications, the application of a cutoff value did not completely exclude false-positive amplification, compromising the specificity and also the sensitivity of the assays.Therefore, although mitochondrial targets have higher sensitivity, they frequently lose specificity due to their high levels of sequence conservation. A screening to evaluate the cross-reaction between Plasmodium species and the non-specific amplification of human malaria-free samples must be performed for Plasmodium mitochondrial assays.","PeriodicalId":73112,"journal":{"name":"Frontiers in tropical diseases","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45723513","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Editorial: Immunology of tuberculosis","authors":"Zhidong Hu, T. Barbosa, X-Y Fan","doi":"10.3389/fitd.2023.1252114","DOIUrl":"https://doi.org/10.3389/fitd.2023.1252114","url":null,"abstract":"","PeriodicalId":73112,"journal":{"name":"Frontiers in tropical diseases","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49166601","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genomic analysis of circulating HIV and hepatitis C virus infections and coinfections in Cameroon: 2005–2006 and 2015–2016","authors":"Sana Tamim, J. Nwobegahay, Armelle Gaelle Fepa Kwesseu, Ida Marlene Guiateu Tamo, Marceline Djuidje Ngounoue","doi":"10.3389/fitd.2023.1094286","DOIUrl":"https://doi.org/10.3389/fitd.2023.1094286","url":null,"abstract":"In humans, RNA viruses are responsible for a wide range of acute, chronic, emerging and re-emerging infections. Human Immunodeficiency virus (HIV) and hepatitis C virus (HCV) rank as some of the most important public health challenges affecting Africa.We performed enzyme-linked immune-sorbent assays to confirm positive specimens, and the genomic characterization on two cohorts of people living with HIV in Douala and Yaoundé for the periods 2005-2006 and 2015-2016. These groups were tested for co-infection with HCV using the enzyme-linked immunosorbent assays. Viral RNA was extracted from positive patients’ plasma samples by QIAGEN method, and specific primers were used to amplify the genes of interest on HIV and HCV genomes. The amplification products were subsequently cloned and sequenced. The nucleotide sequences were aligned, genotyped and phylogenetically analyzed.The HIV isolate identified in this study belongs to HIV-1 group M Subtype A1. The HCV subtypes characterized in this study are 1h and 4t corresponding to the dominant strains that circulate in Cameroon. Phylogenetic analysis of the HCV NS5B gene showed that the study viruses cluster with Gabonese, Canadian, and previously sequenced viruses from Cameroon.These results shed light on the genetic diversity of HIV and HCV in Cameroon. Virulent HCV infections are common in Cameroon, and therefore there is a great need for further analysis of the viral evolutionary and spatio-temporal patterns.","PeriodicalId":73112,"journal":{"name":"Frontiers in tropical diseases","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-07-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47839299","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The first mass drug administration campaign for schistosomiasis control in Lagos, Nigeria: lessons for future control programs","authors":"Francisca O Olamiju, O. Nebe, H. Mogaji, I. Abdus-salam, Lanre Jenrola, Ayodele J. Marcus, Olatunwa J Olamiju, S. Isiyaku, Perpetua Amodu-Agbi, I. Nwoye, Ijeoma Achu, E. Abah","doi":"10.3389/fitd.2023.1094320","DOIUrl":"https://doi.org/10.3389/fitd.2023.1094320","url":null,"abstract":"Background In this study we summarized the lessons learnt during the first effective mass drug administration (MDA) campaign in one of the most urbanized states in Nigeria. We particularly discuss the implementation approach including associated challenges and future prospects. Methods We implemented schistosomiasis MDA with praziquantel in seven endemic districts of the state, using a sub-district/ward-level implementation approach. Upon completion, we conducted desk reviews of field reports and a high-level stakeholder meeting among 95 key personnel involved in the MDA. We reviewed excerpts from the meetings to highlight the strengths, weaknesses, threats and opportunities (SWOT) of the sub-district/ward-level implementation approach. Quantitative data were summarized using basic descriptive statistics, while qualitative data were analyzed to identify emerging themes. Results About 1.45 million children between age 5 and 15 were targeted for treatment, and a geographic (100%) and therapeutic coverage of 85.5% was achieved. Therapeutic coverage was optimal (>75%), across all the implementation districts (Range:76.2- 95.3%). Ifako-Ijaiye had the highest therapeutic coverage (95.3%), while Oshodi-Isolo as the least (76.2%). Strategies supporting high coverage includes; (1) adequate delineation of hard-to reach areas and allocation of commensurate resources, (2) improved consultation and microplanning among programmers, (3) addressing traffic congestion on transportation routes, (4) strengthened engagements and collaborations with community gatekeepers, (5) optimizing cash flow to mitigate financial risk, (6) capacity building of field stakeholders and, (7) regular advocacy and sensitization among stakeholders. Conclusion This study provides possible directions for implementation of schistosomiasis control by programs and agencies at sub-district/ward-level in a cosmopolitan and urbanized state, like that of Lagos, Nigeria.","PeriodicalId":73112,"journal":{"name":"Frontiers in tropical diseases","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44075290","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Case report of cerebral cystic echinococcosis in a 5-year-old child","authors":"Denis Menschaert, A. Daron, J. Frere","doi":"10.3389/fitd.2023.1090644","DOIUrl":"https://doi.org/10.3389/fitd.2023.1090644","url":null,"abstract":"Cystic echinococcosis is a zoonosis caused by the larval form of the tapeworm Echinococcus granulosus. It has a worldwide distribution and represents a particularly significant economic and health burden in endemic areas. The most affected organs are the liver and the lungs. Cerebral involvement is relatively rare. This is a case study of a clinical presentation of cerebral cystic echinococcosis in a 5-year-old female patient of Moroccan origin who had developed recurrent seizures. Currently, diagnosis is based on radiological imaging in the context of anamnestic suspicion. Beyond the conclusions that can be drawn from the various case reports, there are no guidelines on management methods or randomized controlled trials that have compared management methods, and their absence can be deleterious for children. We present this clinical case report to add to the existing ones and to assist clinicians in their therapeutic decision-making while they await guidelines.","PeriodicalId":73112,"journal":{"name":"Frontiers in tropical diseases","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41534893","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Coalescing disparate data sources for the geospatial prediction of mosquito abundance, using Brazil as a motivating case study","authors":"A. Musah, Ella Browning, Aisha Aldosery, Iuri Valerio Graciano Borges, T. Ambrizzi, M. Tunali, Selma Basibüyük, O. Yenigün, G. Moreno, Clarisse Lins de Lima, Ana Clara Gomes da Silva, W. P. dos Santos, T. Massoni, L. Campos, P. Kostkova","doi":"10.3389/fitd.2023.1039735","DOIUrl":"https://doi.org/10.3389/fitd.2023.1039735","url":null,"abstract":"One of the barriers to performing geospatial surveillance of mosquito occupancy or infestation anywhere in the world is the paucity of primary entomologic survey data geolocated at a residential property level and matched to important risk factor information (e.g., anthropogenic, environmental, and climate) that enables the spatial risk prediction of mosquito occupancy or infestation. Such data are invaluable pieces of information for academics, policy makers, and public health program managers operating in low-resource settings in Africa, Latin America, and Southeast Asia, where mosquitoes are typically endemic. The reality is that such data remain elusive in these low-resource settings and, where available, high-quality data that include both individual and spatial characteristics to inform the geospatial description and risk patterning of infestation remain rare. There are many online sources of open-source spatial data that are reliable and can be used to address such data paucity in this context. Therefore, the aims of this article are threefold: (1) to highlight where these reliable open-source data can be acquired and how they can be used as risk factors for making spatial predictions for mosquito occupancy in general; (2) to use Brazil as a case study to demonstrate how these datasets can be combined to predict the presence of arboviruses through the use of ecological niche modeling using the maximum entropy algorithm; and (3) to discuss the benefits of using bespoke applications beyond these open-source online data sources, demonstrating for how they can be the new “gold-standard” approach for gathering primary entomologic survey data. The scope of this article was mainly limited to a Brazilian context because it builds on an existing partnership with academics and stakeholders from environmental surveillance agencies in the states of Pernambuco and Paraiba. The analysis presented in this article was also limited to a specific mosquito species, i.e., Aedes aegypti, due to its endemic status in Brazil.","PeriodicalId":73112,"journal":{"name":"Frontiers in tropical diseases","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42782182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Editorial: Highlights in emerging tropical diseases 2021/22","authors":"J. Gómez‐Marín, W. Villamil-Gómez, A. Rodríguez-Morales","doi":"10.3389/fitd.2023.1199049","DOIUrl":"https://doi.org/10.3389/fitd.2023.1199049","url":null,"abstract":"","PeriodicalId":73112,"journal":{"name":"Frontiers in tropical diseases","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-05-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44813581","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Distribution of genetic diversity of neotropical Biomphalaria (Preston 1910) (Basommatophora: Planorbidae) intermediate hosts for schistosomiasis in Southeast Brazil","authors":"R. Palasio, F. Chiaravalloti-Neto, R. Tuan","doi":"10.3389/fitd.2023.1143186","DOIUrl":"https://doi.org/10.3389/fitd.2023.1143186","url":null,"abstract":"Introduction Biomphalaria glabrata, B. tenagophila, and B. straminea occurrence are crucial for estimating the risk of infectious human schistosomiasis in the neotropics. How different geographic sample strategies influence snail genetic diversity estimations were here investigated for three Schistosoma mansoni hosts. Methods Mitochondrial gene sequences were employed for Cytochrome C Oxidase I (COI), ribosomal RNA (rRNA) 16S, and a dataset with concatenated gene sequences (COI+16S), resulting in an improved scientific hypothesis regarding the geographical distribution of snail species. This study compared the sequences of snails from the Middle Paranapanema (MP) hydrographic basin in a geographically restricted area (inner group) to snails widely distributed across a broad geographical range in São Paulo (outer group), Brazil from 1999 to 2017. DNA sequence polymorphisms and haplotype diversity were estimated using DNAsp software. Haplotype network trees were constructed using a network program. The geographical distribution of the haplotypes was mapped using QGIS. Haplotype variation and distribution were tested for population structure using analysis of molecular variance (AMOVA). Results and discussion The genetic diversity of B. glabrata, sampled from disconnected but geographically close freshwater collections, was partitioned into two sequence groups. The haplotype network showed that the diversity of B. straminea was more spatially partitioned than in B. tenagophila, which exhibited two population groups. The haplotype distribution pattern for B. tenagophila showed many unique and exclusive haplotypes for all three loci. AMOVA showed that genetic diversity could be high in species inhabiting small geographical areas, and a large river is not a local geographical barrier for snail migration. This study found that the survey dimensions and snail samplings influenced the genetic diversity results obtained by mitochondrial DNA molecular markers.","PeriodicalId":73112,"journal":{"name":"Frontiers in tropical diseases","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44643926","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}