Optimising passive surveillance of a neglected tropical disease in the era of elimination: A modelling study

Background Surveillance is an essential component of global programs to eliminate infectious diseases and avert epidemics of (re-)emerging diseases. As the numbers of cases decline, costs of treatment and control diminish but those for surveillance remain high even after the ‘last’ case. Reducing surveillance may risk missing persistent or (re-)emerging foci of disease. Here, we use a simulation-based approach to determine the minimal number of passive surveillance sites required to ensure maximum coverage of a population at-risk (PAR) of an infectious disease. Methodology and principal findings For this study, we use Gambian human African trypanosomiasis (g-HAT) in north-western Uganda, a neglected tropical disease (NTD) which has been reduced to historically low levels (<1000 cases/year globally), as an example. To quantify travel time to diagnostic facilities, a proxy for surveillance coverage, we produced a high spatial-resolution resistance surface and performed cost-distance analyses. We simulated travel time for the PAR with different numbers (1–170) and locations (170,000 total placement combinations) of diagnostic facilities, quantifying the percentage of the PAR within 1h and 5h travel of the facilities, as per in-country targets. Our simulations indicate that a 70% reduction (51/170) in diagnostic centres still exceeded minimal targets of coverage even for remote populations, with >95% of a total PAR of ~3million individuals living ≤1h from a diagnostic centre, and we demonstrate an approach to best place these facilities, informing a minimal impact scale back. Conclusions Our results highlight that surveillance of g-HAT in north-western Uganda can be scaled back without substantially reducing coverage of the PAR. The methodology described can contribute to cost-effective and equable strategies for the surveillance of NTDs and other infectious diseases approaching elimination or (re-)emergence.

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Optimising passive surveillance of a neglected tropical disease in the era of elimination: A modelling study

10.1101/2020.07.20.211714 ◽

2020 ◽

Author(s):

Joshua Longbottom ◽

Charles Wamboga ◽

Paul R. Bessell ◽

Steve J. Torr ◽

Michelle C. Stanton

Keyword(s):

Infectious Diseases ◽

Disease Surveillance ◽

Human African Trypanosomiasis ◽

Cost Effective ◽

Emerging Diseases ◽

Surveillance Systems ◽

Passive Surveillance ◽

Resistance Surface ◽

Western Uganda ◽

North Western

AbstractBackgroundSurveillance is an essential component of global programs to eliminate infectious diseases and avert epidemics of (re-)emerging diseases. As the numbers of cases decline, costs of treatment and control diminish but those for surveillance remain high even after the ‘last’ case. Reducing surveillance may risk missing persistent or (re-)emerging foci of disease. Here, we use a simulation-based approach to determine the minimal number of passive surveillance sites required to ensure maximum coverage of a population at-risk (PAR) of an infectious disease.Methodology and Principal FindingsFor this study, we use Gambian human African trypanosomiasis (g-HAT) in north-western Uganda, a neglected tropical disease (NTD) which has been reduced to historically low levels (<1000 cases/year globally), as an example. To quantify travel time to diagnostic facilities, a proxy for surveillance coverage, we produced a high spatial-resolution resistance surface and performed cost-distance analyses. We simulated travel time for the PAR with different numbers (1-170) and locations (170,000 total placement combinations) of diagnostic facilities, quantifying the percentage of the PAR within 1h and 5h travel of the facilities, as per in-country targets. Our simulations indicate that a 70% reduction (51/170) in diagnostic centres still exceeded minimal targets of coverage even for remote populations, with >95% of a total PAR of ~3million individuals living ≤1h from a diagnostic centre, and we demonstrate an approach to best place these facilities, informing a minimal impact scale back.ConclusionsOur results highlight that surveillance of g-HAT in north-western Uganda can be scaled back without reducing coverage of the PAR. The methodology described can contribute to cost-effective and equable strategies for the surveillance of NTDs and other infectious diseases approaching elimination or (re-)emergence.Author SummaryDisease surveillance systems are an essential component of public health practice and are often considered the first line in averting epidemics for (re-)emerging diseases. Regular evaluation of surveillance systems ensures that they remain operating at maximum efficiency; systems that survey diseases of low incidence, such as those within elimination settings, should be simplified to reduce the reporting burden. A lack of guidance on how to optimise disease surveillance in an elimination setting may result in added expense, and/or the underreporting of disease. Here, we propose a framework methodology to determine systematically the optimal number and placement of surveillance sites for the surveillance of infectious diseases approaching elimination. By utilising estimates of geographic accessibility, through the construction of a resistance surface and a simulation approach, we identify that the number of operational diagnostic facilities for Gambian human African trypanosomiasis in north-western Uganda can be reduced by 70% without affecting existing coverage, and identify the minimum number of facilities required to meet coverage targets. Our analysis can be used to inform the number and positioning of surveillance sites for diseases within an elimination setting. Passive surveillance becomes increasingly important as cases decline and active surveillance becomes less cost-effective; methods to evaluate how best to engage this passive surveillance capacity given facility capacity and geographic distribution are pertinent for several NTDs where diagnosis is complex. Not only is this a complicated research area for diseases approaching elimination, a well-designed surveillance system is essential for the detection of emerging diseases, with this work being topical in a climate where emerging pathogens are becoming more commonplace.

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Glycoprotein- and Lectin-Based Approaches for Detection of Pathogens

Pathogens ◽

10.3390/pathogens9090694 ◽

2020 ◽

Vol 9 (9) ◽

pp. 694

Author(s):

Sammer-ul Hassan ◽

Ahmed Donia ◽

Usman Sial ◽

Xunli Zhang ◽

Habib Bokhari

Keyword(s):

Infectious Diseases ◽

Point Of Care ◽

Healthcare Providers ◽

Basic Research ◽

High Specificity ◽

Cost Effective ◽

Emerging Diseases ◽

Public Healthcare ◽

Point Of Use ◽

Specificity And Sensitivity

Infectious diseases alone are estimated to result in approximately 40% of the 50 million total annual deaths globally. The importance of basic research in the control of emerging and re-emerging diseases cannot be overemphasized. However, new nanotechnology-based methodologies exploiting unique surface-located glycoproteins or their patterns can be exploited to detect pathogens at the point of use or on-site with high specificity and sensitivity. These technologies will, therefore, affect our ability in the future to more accurately assess risk. The critical challenge is making these new methodologies cost-effective, as well as simple to use, for the diagnostics industry and public healthcare providers. Miniaturization of biochemical assays in lab-on-a-chip devices has emerged as a promising tool. Miniaturization has the potential to shape modern biotechnology and how point-of-care testing of infectious diseases will be performed by developing smart microdevices that require minute amounts of sample and reagents and are cost-effective, robust, and sensitive and specific. The current review provides a short overview of some of the futuristic approaches using simple molecular interactions between glycoproteins and glycoprotein-binding molecules for the efficient and rapid detection of various pathogens at the point of use, advancing the emerging field of glyconanodiagnostics.

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Yeast as a Potential Vehicle for Neglected Tropical Disease Drug Discovery

CrossRef Listing of Deleted DOIs ◽

10.1177/1087057114546552 ◽

2014 ◽

Vol 20 (1) ◽

pp. 56-63 ◽

Cited By ~ 13

Author(s):

P.W. Denny ◽

P.G. Steel

Keyword(s):

Drug Discovery ◽

High Throughput ◽

High Throughput Screening ◽

Cost Effective ◽

Eukaryotic Cell ◽

Tropical Disease ◽

Neglected Tropical Disease ◽

Cellular Context ◽

Basic Approaches

High-throughput screening (HTS) efforts for neglected tropical disease (NTD) drug discovery have recently received increased attention because several initiatives have begun to attempt to reduce the deficit in new and clinically acceptable therapies for this spectrum of infectious diseases. HTS primarily uses two basic approaches, cell-based and in vitro target-directed screening. Both of these approaches have problems; for example, cell-based screening does not reveal the target or targets that are hit, whereas in vitro methodologies lack a cellular context. Furthermore, both can be technically challenging, expensive, and difficult to miniaturize for ultra-HTS [(u)HTS]. The application of yeast-based systems may overcome some of these problems and offer a cost-effective platform for target-directed screening within a eukaryotic cell context. Here, we review the advantages and limitations of the technologies that may be used in yeast cell–based, target-directed screening protocols, and we discuss how these are beginning to be used in NTD drug discovery.

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Design for the Post-Antibiotic Era: Experiences from a New Building for Infectious Diseases in Malmö, Sweden

HERD Health Environments Research & Design Journal ◽

10.1177/193758671300600403 ◽

2013 ◽

Vol 6 (4) ◽

pp. 27-52 ◽

Cited By ~ 4

Author(s):

Torsten Holmdahl ◽

Peter Lanbeck

Keyword(s):

Infectious Diseases ◽

Infection Control ◽

Cost Effective ◽

Emerging Diseases ◽

Control Measures ◽

Evidence Based ◽

Active Involvement ◽

Infection Control Measures ◽

Building Process ◽

New Facility

OBJECTIVE: To describe the experience of planning and designing a new facility for infectious diseases in Sweden and to discuss underlying theories relating to infection prevention and evidence-based design. BACKGROUND: Departments of Infectious Diseases are common in healthcare facililties in Sweden. In 2005, a decision was made to build a new facility. The program required spacious single rooms, with a high ventilation standard, and anterooms. METHODS: In this article we present an analysis of the future of infectious diseases. Underlying theories are discussed. We also describe how a program was outlined using literature studies, including evidence-based healthcare design, focus groups of staff, and study visits. RESULTS: Active involvement of users and infection control specialists was important in the building process. A full-scale patient room mock-up was built with ventilation, electrical, and other systems. The mock-up was cost effective because it avoided costly mistakes during the building process. The mock-up also was a place where staff could assess and begin adapting to their future work environment. Separate ventilation and separate entrances to patient rooms from the building exterior allowed placement of isolation units in the main hospital area. CONCLUSIONS: Antimicrobial resistance, emerging diseases, healthcare associated infections, and outbreaks highlight the need for infection control measures in all hospital design. Infection control should be integrated in all hospital planning and be part of contracts. In this study we describe a specialized unit where a high degree of standardization and flexibility has made it possible to have a unique standard of preparedness for the post-antibiotic era.

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Development of Novel Therapeutics for Neglected Tropical Disease Leishmaniasis

10.21236/ada637013 ◽

2015 ◽

Author(s):

Abhay Satoskar

Keyword(s):

Tropical Disease ◽

Neglected Tropical Disease ◽

Novel Therapeutics

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Multi-Epitope Vaccines (MEVs), as a Novel Strategy Against Infectious Diseases

Current Proteomics ◽

10.2174/1570164617666190919120140 ◽

2020 ◽

Vol 17 (5) ◽

pp. 354-364

Author(s):

Mohammad Mahmoudi Goumari ◽

Ibrahim Farhani ◽

Navid Nezafat ◽

Shirin Mahmoodi

Keyword(s):

Infectious Diseases ◽

Epitope Prediction ◽

Cost Effective ◽

Antimicrobial Drugs ◽

Antibiotic Resistant ◽

Time Consumption ◽

Preclinical Evaluation ◽

Structural Evaluation ◽

Novel Strategy ◽

Epitope Vaccines

Infectious diseases have caused historical pandemics in the world. Three strategies, including sanitation programs, antimicrobial drugs, and vaccines are considered for the prevention and treatment of infectious diseases. Today, some infectious diseases cause millions of mortalities universally. Due to the emergence of antibiotic-resistant pathogens, as well as some limitations of traditional vaccines, focusing on novel strategies is essential. Multi-Epitope Vaccines (MEVs), as a novel strategy, have been designed based on immunoinformatics methods; epitope prediction by authentic servers, attachment of epitopes using proper linkers, physicochemical, immunological and structural evaluation by bioinformatics tools that are basic stages in MEVs designing. Advantages such as cost-effective, high safety, less time consumption in designing, the application of natural adjuvants, and satisfactory preclinical evaluation outstand MEVs than other types of vaccines. Therefore, MEVs are promising vaccines against resistant diseases such as lower respiratory infection and diarrhea.

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Platforms for Production of Protein-Based Vaccines: From Classical to Next-Generation Strategies

Biomolecules ◽

10.3390/biom11081072 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1072

Author(s):

Raquel Cid ◽

Jorge Bolívar

Keyword(s):

Infectious Diseases ◽

Mammalian Cells ◽

Vaccine Development ◽

Low Cost ◽

Cost Effective ◽

Insect Larvae ◽

Subunit Vaccines ◽

Effective Strategies ◽

Alternative Systems ◽

Inactivated Vaccines

To date, vaccination has become one of the most effective strategies to control and reduce infectious diseases, preventing millions of deaths worldwide. The earliest vaccines were developed as live-attenuated or inactivated pathogens, and, although they still represent the most extended human vaccine types, they also face some issues, such as the potential to revert to a pathogenic form of live-attenuated formulations or the weaker immune response associated with inactivated vaccines. Advances in genetic engineering have enabled improvements in vaccine design and strategies, such as recombinant subunit vaccines, have emerged, expanding the number of diseases that can be prevented. Moreover, antigen display systems such as VLPs or those designed by nanotechnology have improved the efficacy of subunit vaccines. Platforms for the production of recombinant vaccines have also evolved from the first hosts, Escherichia coli and Saccharomyces cerevisiae, to insect or mammalian cells. Traditional bacterial and yeast systems have been improved by engineering and new systems based on plants or insect larvae have emerged as alternative, low-cost platforms. Vaccine development is still time-consuming and costly, and alternative systems that can offer cost-effective and faster processes are demanding to address infectious diseases that still do not have a treatment and to face possible future pandemics.

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Aliphatic extractive effects on acetic acid catalysis of typical agricultural residues to xylo-oligosaccharide and enzymatic hydrolyzability of cellulose

Biotechnology for Biofuels ◽

10.1186/s13068-021-01952-8 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Jianming Guo ◽

Kaixuan Huang ◽

Rou Cao ◽

Junhua Zhang ◽

Yong Xu

Keyword(s):

Acetic Acid ◽

Acid Catalysis ◽

Cost Effective ◽

Economic Benefits ◽

Ethanol Extraction ◽

Minimal Impact ◽

Aliphatic Compounds ◽

Organic Solvent Extraction ◽

Promising Application ◽

Poplar Sawdust

Abstract Background Xylo-oligosaccharide is the spotlight of functional sugar that improves the economic benefits of lignocellulose biorefinery. Acetic acid acidolysis technology provides a promising application for xylo-oligosaccharide commercial production, but it is restricted by the aliphatic (wax-like) compounds, which cover the outer and inner surfaces of plants. Results We removed aliphatic compounds by extraction with two organic solvents. The benzene–ethanol extraction increased the yield of acidolyzed xylo-oligosaccharides of corncob, sugarcane bagasse, wheat straw, and poplar sawdust by 14.79, 21.05, 16.68, and 7.26% while ethanol extraction increased it by 11.88, 17.43, 1.26, and 13.64%, respectively. Conclusion The single ethanol extraction was safer, more environmentally friendly, and more cost-effective than benzene–ethanol solvent. In short, organic solvent extraction provided a promising auxiliary method for the selective acidolysis of herbaceous xylan to xylo-oligosaccharides, while it had minimal impact on woody poplar.

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