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The emergence of multicancer early detection (MCED) tests holds promise for improving early cancer detection and public health outcomes. However, positive MCED test results require confirmation through recommended cancer diagnostic imaging modalities. To address these challenges, we have developed a consultation and work-up protocol for definitive diagnostic results post MCED testing, named SPOT-MAS. Developed through circulating tumor DNA (ctDNA) analysis and in line with professional guidelines and advisory board consensus, this protocol standardizes information to aid general practitioners in accessing, interpreting and managing SPOT-MAS results. Clinical effectiveness is demonstrated through a series of identified cancer cases. Our research indicates that the protocol could empower healthcare professionals to confidently interpret circulating tumor DNA test results for 5 common types of cancer, thereby facilitating the clinical integration of MCED tests.

Despite their promise, circulating tumor DNA (ctDNA)-based assays for multi-cancer early detection face challenges in test performance, due mostly to the limited abundance of ctDNA and its inherent variability. To address these challenges, published assays to date demanded a very high-depth sequencing, resulting in an elevated price of test. Herein, we developed a multimodal assay called SPOT-MAS (screening for the presence of tumor by methylation and size) to simultaneously profile methylomics, fragmentomics, copy number, and end motifs in a single workflow using targeted and shallow genome-wide sequencing (~0.55×) of cell-free DNA. We applied SPOT-MAS to 738 non-metastatic patients with breast, colorectal, gastric, lung, and liver cancer, and 1550 healthy controls. We then employed machine learning to extract multiple cancer and tissue-specific signatures for detecting and locating cancer. SPOT-MAS successfully detected the five cancer types with a sensitivity of 72.4% at 97.0% specificity. The sensitivities for detecting early-stage cancers were 73.9% and 62.3% for stages I and II, respectively, increasing to 88.3% for non-metastatic stage IIIA. For tumor-of-origin, our assay achieved an accuracy of 0.7. Our study demonstrates comparable performance to other ctDNA-based assays while requiring significantly lower sequencing depth, making it economically feasible for population-wide screening.

Vocational orientation is a concerned topic in the Vietnamese new general education program. However, the current high school vocational programs have not yet met the need for innovation in the student competence development orientation, thus leading to high school vocational orientation has not been effective. This study proposes a vocational school-based program approached from a new individual guidance. By using the pre-experiment and post-experiment questionnaire to evaluate the feasibility and effectiveness of the proposed program to the quality of vocational orientation, the results showed that students' awareness of vocational school-based programs changed in a positive direction. The proposed program proves its effectiveness when applied in schools by combining the practical career experience and vocational counseling, or the combination of individual experience and social interaction in choosing a suitable career. This finding overcomes the disadvantages of the old vocational school-based program and can be applied to adapt the student competence development orientation in the Vietnamese general education program.

ABSTRACTThe use of eggshells as an alternative source of calcium carbonate for groundnut can reduce the impact on the natural reserves of limestone, a non-renewable natural source. This study aimed to investigate the effects of eggshell powder application on the growth and yield of groundnut. The calcium treatments were lime application (A0) at 500 kg ha−1 and four rates of eggshell powder application including A1 (200 kg ha−1), A2 (300 kg ha−1), A3 (400 kg ha−1), and A4 (500 kg ha−1). Two application times, T1 (applying 5-days before sowing) and T2 (applying 5-days after flowering) were employed. The result showed that eggshell powder could be a useful alternative source to supply Ca for groundnut. Application of eggshell powder before sowing resulted in significantly higher pod yield and total calcium uptake with better growth parameters than after flowering. Increasing eggshell powder application rates also increased soil pH and calcium contents, and plant calcium uptake. The application rate of eggshell powder before sowing at the rate of 300 kg ha−1 produced the highest pod yield and was suggested to be optimum.

Summary: Background: Encephalitis is a worldwide public health issue, with a substantially high burden among children in southeast Asia. We aimed to determine the causes of encephalitis in children admitted to hospitals across the Greater Mekong region by implementing a comprehensive state-of-the-art diagnostic procedure harmonised across all centres, and identifying clinical characteristics related to patients’ conditions. Methods: In this multicentre, observational, prospective study of childhood encephalitis, four referral hospitals in Cambodia, Vietnam, Laos, and Myanmar recruited children (aged 28 days to 16 years) who presented with altered mental status lasting more than 24 h and two of the following minor criteria: fever (within the 72 h before or after presentation), one or more generalised or partial seizures (excluding febrile seizures), a new-onset focal neurological deficit, cerebrospinal fluid (CSF) white blood cell count of 5 per mL or higher, or brain imaging (CT or MRI) suggestive of lesions of encephalitis. Comprehensive diagnostic procedures were harmonised across all centres, with first-line testing was done on samples taken at inclusion and results delivered within 24 h of inclusion for main treatable causes of disease and second-line testing was done thereafter for mostly non-treatable causes. An independent expert medical panel reviewed the charts and attribution of causes of all the included children. Using multivariate analyses, we assessed risk factors associated with unfavourable outcomes (ie, severe neurological sequelae and death) at discharge using data from baseline and day 2 after inclusion. This study is registered with ClinicalTrials.gov, NCT04089436, and is now complete. Findings: Between July 28, 2014, and Dec 31, 2017, 664 children with encephalitis were enrolled. Median age was 4·3 years (1·8–8·8), 295 (44%) children were female, and 369 (56%) were male. A confirmed or probable cause of encephalitis was identified in 425 (64%) patients: 216 (33%) of 664 cases were due to Japanese encephalitis virus, 27 (4%) were due to dengue virus, 26 (4%) were due to influenza virus, 24 (4%) were due to herpes simplex virus 1, 18 (3%) were due to Mycobacterium tuberculosis, 17 (3%) were due to Streptococcus pneumoniae, 17 (3%) were due to enterovirus A71, 74 (9%) were due to other pathogens, and six (1%) were due to autoimmune encephalitis. Diagnosis was made within 24 h of admission to hospital for 83 (13%) of 664 children. 119 (18%) children had treatable conditions and 276 (42%) had conditions that could have been preventable by vaccination. At time of discharge, 153 (23%) of 664 children had severe neurological sequelae and 83 (13%) had died. In multivariate analyses, risk factors for unfavourable outcome were diagnosis of M tuberculosis infection upon admission (odds ratio 3·23 [95% CI 1·04–10·03]), coma on day 2 (2·90 [1·78–4·72]), supplementary oxygen requirement (1·89 [1·25–2·86]), and more than 1 week duration between symptom onset and admission to hospital (3·03 [1·68–5·48]). At 1 year after inclusion, of 432 children who were discharged alive from hospital with follow-up data, 24 (5%) had died, 129 (30%) had neurological sequelae, and 279 (65%) had completely recovered. Interpretation: In southeast Asia, most causes of childhood encephalitis are either preventable or treatable, with Japanese encephalitis virus being the most common cause. We provide crucial information that could guide public health policy to improve diagnostic, vaccination, and early therapeutic guidelines on childhood encephalitis in the Greater Mekong region. Funding: Institut Pasteur, Institut Pasteur International Network, Fondation Merieux, Aviesan Sud, INSERM, Wellcome Trust, Institut de Recherche pour le Développement (IRD), and Fondation Total.

Abstract Background Dengue virus (DENV) is a member of insect vector-borne viruses, and it causes dengue fever. Southeast Asia is the epi-center of dengue fever in the world. The characterization of the virus is essential to identify the transmission and evolution of DENV. Objectives In 2017, there was an outbreak of Dengue virus type 1 (DENV1) in northern Vietnam and the neighboring countries. To identify the genetic character of the outbreak virus in the area, we conducted whole-genome sequencing analysis on the samples positive for the DENV1 along with real-time PCR. Study design In total, 1026 blood samples were collected from patients with suspected dengue fever in Ha Nam and Hai Duong province, nearby areas of the capital of Vietnam. After screening by real-time PCR, 40 of DENV1 positive samples were subjected to whole-genome sequencing, and 28 complete coding sequences were obtained. Results All 28 sequences were genotype I of DENV1, which is dominant in the southeast and East Asian countries. The phylogenetic analysis of the E region showed that they fell into a single cluster with the reported sequences from Vietnam between 2009 and 2016, in which the isolates from other countries are very rare. Our results suggested that the 2017 outbreak in the area was caused by locally circulating viruses.

Cultural globalization is the fierce and unavoidable tendency that has powerfully influenced the culture of each nation or ethnicity, especially the cultures of developing countries. They are worried about the uniformity of the world culture, which will fade away cultural identity diversity. This paper analyzes some threat and chances of the globalization process and point out several solutions that Vietnam has applied and practiced to preserve cultural identity in the context of cultural globalization.

Abstract Background Between 2016 and 2019, 265 cases of Zika virus (ZIKV) infection were reported in Vietnam, predominantly in southern Vietnam. In 2016, a case of ZIKV-associated microcephaly was confirmed in the Central Highlands, and several members of the infant’s family were confirmed to be infected with ZIKV. The study aims to determine the level of immunity to ZIKV in the general population of the ZIKV epidemic region. Methods A total of 879 serum samples were collected from 801 participants between January 2017 and July 2018, during and after the ZIKV epidemic in Vietnam. The samples were tested for anti-ZIKV immunoglobulin M (IgM) and immunoglobulin G (IgG), and anti-dengue virus (DENV) IgG antibodies using enzyme-linked immunosorbent assays (ELISA). Plaque-reduction neutralization test (PRNT) for ZIKV was performed on all samples, and for DENV on the samples that ZIKV neutralizing antibody positive. Results A total of 83 (10.3%) participants had anti-ZIKV IgM. Of the 83, 6 were confirmed to be ZIKV antibodies positive using PRNT and anti-ZIKV IgG ELISA. Of the 718 participants who were anti-ZIKV IgM negative, a further 3 cases were confirmed as positive for antibodies against ZIKV. Of the 9 participants with ZIKV infection, 5 lived in the same village as the infant with ZIKV-associated microcephaly and the other 4 lived in 2 neighboring communes. Repeat samples were collected from the 83 ZIKV IgM positive participants 1.5 years after the first collection. No new cases of ZIKV infection were detected. In addition, 2 of 3 participants with anti-ZIKV NS1 IgG demonstrated a 4- to 8-fold increase in ZIKV neutralizing antibody titer. Conclusions ZIKV was present in the area around Krong Buk, with the rate of ZIKV-specific antibodies was 1.1% in the community since at least 2016. While the low levels of circulation together with low seroprevalence suggests a limited outbreak in the region, the results also reflect on low levels of protective immunity to Zika within the population. These results provide a better understanding of the current ZIKV epidemic status in the region and demonstrate a need for implementation of more effective ZIKV infection control measures.

Proverbs as a section of language are a folklore genre that contains much knowledge, wisdom, philosophy, behavior of nations. Research on proverbs themselves is always an interesting job attracting many scholars. More particularly, research on proverbs as tools by language-culture relationship perspective to deeply understand cultures is a much harder task. Using an interdisciplinary approach and typological method in Comparative cultural studies based on the data of more than 151 proverbs processed, the findings of this article will introduce some cultural features of Polish and Vietnamese people as well as East and West. It is just a channel to prove that research on proverbs can help research on culture to affirm the differences and similarities in thought and behavior. Accordingly, this will help the communication and cultural interchange, cooperation, and education better and more effectively.

This article provides an overview of environmental accounting for sustainable development such as approach, measurement of sustainable accounting and assess the impact of factors on the application of environmental accounting for sustainable development. The information of 80 companies used for research have been representatively selected from manufacturing, mining and processing industries, state ownership and nonstate ownership, in export processing zones and outside export processing zones at all scales of number of employees, equity, reve-nue in Vietnam. Data is analyzed using multivariate linear regression. Research shows that factors such as managers' perceptions of costs and benefits, environmental changes, characteristics of the scale of production and business activities of enterprises, pressures to announce sustainable environmental information and reporting have significant influences on the development of environmental accounting for sustainable development.

In recent years, serosurveillance has gained momentum as a way of determining disease transmission and immunity in populations, particularly with respect to vaccine-preventable diseases. At the end of 2017, the Oxford University Clinical Research Unit and the National Institute of Hygiene and Epidemiology held a meeting in Vietnam with national policy makers, researchers, and international experts to discuss current seroepidemiologic projects in Vietnam and future needs and plans for nationwide serosurveillance. This report summarizes the meeting and the plans that were discussed to set up nationwide serosurveillance in Vietnam.

Trong nghiên cứu này, vật liệu nano bạc (AgNPs) được tổng hợp bằng phương pháp khử hóa học với chất khử là natri citrate và chất bảo vệ là alginate. Các thông số ảnh hưởng tới quá trình tổng hợp nano bạc gồm nồng độ natri citrate, nồng độ bạc nitrate, nồng độ alginate và nhiệt độ của hệ phản ứng đã được nghiên cứu. Sự hình thành AgNPs, hình thái và cấu trúc của vật liệu sau khi tổng hợp được phân tích bằng quang phổ hấp thụ phân tử, hiển vi điện tử quét, hiển vi điện tử truyền qua và nhiễu xạ tia X. AgNPs có hiệu lực ức chế cao đối với nấm Pyricularia oryzae gây bệnh đạo ôn trên cây lúa.

Abstract Background Hospital nurses are exposed to various work-related factors that may be associated with increased risk of developing different mental disorders. Empirical evidence on the prevalence and correlates of individual mental health problems such as stress, anxiety and depression is widely reported, while a combined pattern of these conditions is unknown. This study aims to examine the co-occurrence of stress, anxiety and depression among clinical nurses, and to explore socio-demographic characteristics of, and working conditions experienced by, nurses that may be associated with these three mental health conditions. Methods A cross-sectional study was implemented in one tertiary hospital in Hanoi city, Vietnam, from May to September 2015. A self-reported questionnaire including a short version of the Depression, Anxiety and Stress scale 21 items and questions on demographic and work-related characteristics was delivered to 787 registered nurses. 600 completed questionnaires was used in the final analysis (76.2% response rate). The two-step clustering analysis was performed to identify sub groups. Chi square test and post hoc ANOVA analysis with Bonferroni correction were used to examine differences in psychological status, demographic characteristics and working conditions among the clusters (two-tailed p

In this paper, the impact of the jamming signal on the secrecy performance of Energy Harvesting (EH) enabled dual-hop amplify-and-forward relaying network is investigated. First, the security outage probability analysis is studied for conventional networks under a single passive eavesdropper attack. Then, the outage performance analysis in two cases regarding energy harvesting is investigated. Moreover, the proposed work enhances Physical Layer (PHY) security performance of two-hop relaying model using Cooperative Jamming Dual-Hop Techniques (CJDH). For this purpose, new closed-form expressions are derived for the outage probability of CJDH model in the presence of interference over Rayleigh fading channels. A power allocation optimization problem for energy harvesting protocol is formulated and solved for enhancing the system security. The derived analytical formulas herein are supported by numerical and simulation results to clarify the main contributions of the paper.

Copper lighter tetrylenes are promising for inhibition towards Rhizoctonia solani-based protein PDB-4G9M and Magnaporthe oryzae-based PDB-6JBR in rice. Quantum properties of four hypothetic copper complexes of carbenes and silylenes (Cu-NHC1, Cu-NHC2, Cu-NHSi1, and Cu-NHSi2) were examined using the density functional theory. Their inhibitability towards the targeted proteins was evaluated using molecular docking simulation. Quantum analysis predicts the stability of the investigated complexes and thus their practical existability and practicable synthesisability. Their electronic configurations are justified as highly conducive to intermolecular interaction. Regarding ligand-protein as carbenes/silylenes-4G9M inhibitory structures, the stability is estimated in the order [Cu-NHC2]-4G9M (DS −12.9 kcal⋅mol−1) > [Cu-NHSi1]-4G9M (DS −11.8 kcal⋅mol−1) = [Cu-NHSi2]-4G9M (DS −11.7 kcal⋅mol−1) > [Cu-NHC1]-4G9M (DS –11.4 kcal⋅mol−1). In contrast, the corresponding order for the carbenes/silylenes-6JBR systems is [Cu-NHSi2]-6JBR (DS –13.4 kcal⋅mol−1) > [Cu-NHC2]-6JBR (DS −13.0 kcal⋅mol−1) = [Cu-NHSi1]-6JBR (DS −12.6 kcal⋅mol−1) > [Cu-NHC1]-6JBR (DS −12.3 kcal⋅mol−1). In theory, this study suggests a potentiality of copper lighter tetrylenes and their derivatives against the infection of fungi Rhizoctonia solani and Magnaporthe oryzae, thus encouraging attempts for experimental developments.

This paper summarizes some of the essential aspects for the fabrication of functional devices from bottom-up silicon nanowires. In a first part, the different ways of exploiting nanowires in functional devices, from single nanowires to large assemblies of nanowires such as nanonets (two-dimensional arrays of randomly oriented nanowires), are briefly reviewed. Subsequently, the main properties of nanowires are discussed followed by those of nanonets that benefit from the large numbers of nanowires involved. After describing the main techniques used for the growth of nanowires, in the context of functional device fabrication, the different techniques used for nanowire manipulation are largely presented as they constitute one of the first fundamental steps that allows the nanowire positioning necessary to start the integration process. The advantages and disadvantages of each of these manipulation techniques are discussed. Then, the main families of nanowire-based transistors are presented; their most common integration routes and the electrical performance of the resulting devices are also presented and compared in order to highlight the relevance of these different geometries. Because they can be bottlenecks, the key technological elements necessary for the integration of silicon nanowires are detailed: the sintering technique, the importance of surface and interface engineering, and the key role of silicidation for good device performance. Finally the main application areas for these silicon nanowire devices are reviewed.

Dendritic cells (DC) are professional antigen-presenting cells that activate T cells to kill cancer cells. The extracellular products of DCs have also been reported to perform the same function. In this study, we examined the in vitro differentiation of umbilical cord blood monocytes into DCs in the presence of GM-CSF, and interferon (IFN)-α. The resulting DC population (called IFN-DCs) were then matured in the presence of TNF-α, and pulsed with total protein extracted from A549 cancer cell line. The pulsed DCs and their conditioned medium were then used to stimulate allogeneic lymphocytes (alloLym). The proliferation and cytotoxicity of alloLym were then determined. The results showed that after 5 days of differentiation, the stimulated monocytes had the typical morphology and characteristic surface markers of DCs. Both unpulsed and pulsed IFN-DCs can induce the proliferation of alloLym, especially Vγ9γδ T cells. The conditioned medium from pulsed and unpulsed IFN-DCs culture also prompted the growth of Vγ9γδ T cells. Moreover, alloLym stimulated with pulsed DCs and their conditioned medium had a greater cytotoxic effect on A549 cells than the ones that were not stimulated. Our results indicated that IFN-DCs and their conditioned medium could induce the anti-tumor immunity in vitro , providing evidence for application of cord blood monocytes-derived, interferon-α- stimulated dendritic cells and their extracellular products in anti-cancer therapy.

This cross-sectional study is to examine the prevalence of depression and associated factors among 110 ethnic minority elderly in Kon Tum city, Vietnam. Depression was assessed using 30-items Geriatric Depression Scale. Multivariate linear regression analysis was employed to identify factors associated with depression. The prevalence of depression among participants was 25.5%. All were classified as mild depression level. Depression was significantly associated with age, gender, educational level, chronic diseases, stressful life events in the past 12 months, and family history of depression. These risk factors can help formulate effective public health programs to improve mental health among ethnic minority elderly.

Background: Achieving access to clean water and basic sanitation remains as major challenges in Vietnam, especially for vulnerable groups such as minority people, despite all the progress made by the Millennium Development Goal number 7.C. Objectives: The study aimed to describe the access to improved water sources and sanitation of the ethnic minority people in Vietnam based on a national survey and to identify associated factors. Methods: A cross-sectional study was conducted in 2019 with a sample size of 1385 ethnic minority households in 12 provinces in Vietnam. Multivariate logistic regression modeling was performed to examine the probability of having access to improved water sources and sanitation and sociodemographic status at a significance level of P

The relaxation dynamics and thermodynamic properties of supercooled and glassy gambogic acid are investigated using both theory and experiment. We measure the temperature dependence of the relaxation times in three polymorphs (α-, β-, and γ-form). To gain insight into the relaxation processes, we propose a theoretical approach to quantitatively understand the nature of these three relaxations. The α-relaxation captures cooperative motions of molecules, while the β-process is mainly governed by the local dynamics of a single molecule within the cage formed by its nearest neighbors. Based on quantitative agreement between theory and experimental data, our calculations clearly indicate that the β-process is a precursor of the structural relaxation and intramolecular motions are responsible for the γ-relaxation. Moreover, the approach is exploited to study the effects of the heating process on alpha relaxation. We find that the heating rate varies logarithmically with Tg and 1000/Tg. These variations are qualitatively consistent with many prior studies.

Monofloral honey samples (Coffea robusta) from Vietnam were determined for their chemical compositions. This is the first report on the chemical composition and antioxidant activity of coffee honey from Vietnam. These samples were characterized by their high contents of total and reducing sugars, total phenolic contents, and total flavonoid contents. The contents of seven phenolic acids (PAs) were quantified by high performance liquid chromatography (HPLC) and analyzed with the assistance of principle component analysis (PCA) to differentiate the honey samples into groups. The hydroxymethylfurfural (HMF) (0.048–2.933 mg/kg) and free acid contents (20.326–31.163 meq/kg) of coffee honey were lower in Nepal, which reflected the freshness of the honey when conducting this survey. The coffee honey had total sugar and reducing sugar contents 831.711 g/kg and 697.903 g/kg, respectively. The high level of total phenolic (0.642 mg GAE/g) and flavonoid (0.0341 mg GE/g) contents of coffee honey contributed to their antioxidant activity of this honey sample. Among the coffee honey tested, the IC50 of DPPH radical-scavenging activities value was 1.134–17.031 mg/mL, while the IC50 of ABTS radical-scavenging activities value was 115.381–213.769 mg/mL. The phenolic acids composition analysis displayed that gallic acid appeared in high concentrations in all studied honey samples, ranging from 0.037–1.015 mg/kg, and ferulic acid content ranged from 0.193 to 0.276 mg/kg. The content of trigonelline and caffeine in coffee honey samples ranged from 0.314–2.399 mg/kg and 8.946–37.977 mg/kg. The data in this article highlight the relevance of coffee honey as a healthy substance.

Background: Rapid urbanization combined with rural migration to urban areas in southern Vietnam could be risk factors for allergen sensitization, contributing to chronic respiratory diseases (CRD). We aimed to evaluate the prevalence of mite sensitization and its relation to house dust characteristics among rural and urban native and migrating populations with CRD. Methods: Rural (n = 19) and urban (n = 46) dwellings were defined on the basis of a home typology. Controls were western Belgian houses (n = 14). Besides the house characteristics, both endotoxin and mite allergens were measured in the settled dusts. The sensitization to mite allergens was defined by positive skin prick test (SPT) and concentration of specific IgE (sIgE)≥ 0.7 U/mL. The prevalence of mite sensitization was evaluated among 610 patients with CRD and compared according to both their home types and places of birth and residences. Results: The concentration of endotoxin (but not mite allergen) was higher in rural compared to urban dusts (440 (95%CI: 314–566) versus 170 (95%CI: 115–226) EU/mg; p

Abstract Background Antibodies are critical responses to protect the host from dengue virus(DENV) infection. Antibodies target DENV by two pathologic mechanisms: virus neutralization and infection enhancement. In dengue patients, the absence of neutralizing activity in the presence of FcγR implies that infection-enhancing activity hampers the neutralizing activity of antibodies, which could potentially lead to symptomatic presentations and severe clinical outcomes. Methods A total of 100 pair serum samples from adult healthy volunteers were obtained during the dengue season in Ha Noi in 2015 for evaluation of neutralizing and infection-enhancing activity. Additionally, 20 serum samples from acute secondary DENV infection patients were also used as the patient group in this study. PRNT was performed on BHK cells and FcγR-expressing BHK cell lines for all serum samples. Results Out of 100 residents, positive neutralizing antibodies (N.A) were found in 44.23 and 76.92% for DENV-1; 38.46 and 75% for DENV-2; 19.23 and 15.38% for DENV-3; and 1.92 and 9.62% for DENV-4 for pre and post-dengue season respectively. The percentage of post-exposure residents having positive responses against single, two, or more than three DENV serotypes were 38.46, 44.23 and 15.38%, respectively. A total of 34 residents were DENV seropositive before the dengue season and these individuals demonstrated further elevation of IgG antibodies after the dengue season. At the end of the season, 18 residents were confirmed to be new asymptomatic DENV infection cases. In both groups, N.A titers determined on BHK cells were higher than that on FcγR-expressing BHK cells. In heterotypic N.A responses, N.A titers to the infecting serotype from the samples obtained from pre-exposure group were significantly higher than those of the patient group. However, fold enhancement to the infecting serotypes from the samples in the pre-exposure group was substantially lower as compared to that of the patient group. Conclusion Before and after the dengue season, serum samples from healthy volunteers demonstrated high levels of neutralizing antibodies and low or absence of infection-enhancement activity. The results suggest that while infection-enhancement activity hampers neutralizing activity of antibodies, high levels of DENV neutralizing antibodies set a critical threshold in facilitating the prevention of disease progression.