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It is essential that communities at risk from TB are involved in TB research. Community advisory groups (CAGs) are one mechanism for involving communities in research and creating platforms for discussions between researchers and community members. We organised a CAG meeting with community members and people with lived experience in Ho Chi Minh City, Vietnam, to explore the community's knowledge about TB and their perspectives on different diagnostic tests in Vietnam, a low-middle-income country with a high TB burden. Researchers shared basic information and addressed questions about TB. CAG members commented on preference of TB screening tests, and suggested that chest X-rays and blood tests were more acceptable than sputum tests because of the difficulty in sputum expectoration. In addition, clinical studies that required fewer visits to the hospitals would be preferred, even if this meant a greater reliance on blood sampling., Competing Interests: Conflicts of interest: none declared., (© 2024 The Authors.)

Background: The protective or pathogenic role of T lymphocytes during the acute phase of dengue virus (DENV) infection has not been fully understood despite its importance in immunity and vaccine development. Objectives: This study aimed to clarify the kinetics of T lymphocyte subsets during the clinical course of acute dengue patients. Study design: In this hospital-based cohort study, 59 eligible Vietnamese dengue patients were recruited and admitted. They were investigated and monitored for T cell subsets and a panel of clinical and laboratory parameters every day until discharged and at post-discharge from the hospital. Results: We described for the first time the kinetics of T cell response during the clinical course of DENV infection. Severe cases showed significantly lower levels of effector CD8 + T cells compared to mild cases at day -1 ( p = 0.017) and day 0 ( p = 0.033) of defervescence. After defervescence, these cell counts in severe cases increased rapidly to equalize with the levels of mild cases. Our results also showed a decline in total CD4 + T, Th1, Th1/17 cells during febrile phase of dengue patients compared to normal controls or convalescent phase. On the other hand, Th2 cells increased during DENV infection until convalescent phase. Cytokines such as interferon-γ, IL-12p70, IL-5, IL-23, IL-17A showed tendency to decrease on day 0 and 1 compared with convalescence and only IL-5 showed significance indicating the production during acute phase was not systemic. Conclusion: With a rigorous study design, we uncovered the kinetics of T cells in natural DENV infection. Decreased number of effector CD8 + T cells in the early phase of infection and subsequent increment after defervescence day probably associated with the T cell migration in DENV infection., (Copyright © 2020 Manh, Weiss, Thuong, Mizukami, Dumre, Luong, Thanh, Thang, Huu, Phuc, Nhung, Mai, Truong, Ngu, Quoc, Ha, Ton, An, Halhouli, Quynh, Kamel, Karbwang, Huong, Huy and Hirayama.)

Background: Considerable progress has been made in dengue management, however the lack of appropriate predictors of severity has led to huge number of unwanted admissions mostly decided on the grounds of warning signs. Apoptosis related mediators, among others, are known to correlate with severe dengue (SD) although no predictive validity is established. The objective of this study was to investigate the association of plasma cell-free DNA (cfDNA) with SD, and evaluate its prognostic value in SD prediction at acute phase., Methods: This was a hospital-based prospective cohort study conducted in Vietnam. All the recruited patients were required to be admitted to the hospital and were strictly monitored for various laboratory and clinical parameters (including progression to SD) until discharged. Plasma samples collected during acute phase (6-48 h before defervescence) were used to estimate the level of cfDNA., Results: Of the 61 dengue patients, SD patients (n = 8) developed shock syndrome in 4.8 days (95% CI 3.7-5.4) after the fever onset. Plasma cfDNA levels before the defervescence of SD patients were significantly higher than the non-SD group (p = 0.0493). From the receiver operating characteristic (ROC) curve analysis, a cut-off of > 36.9 ng/mL was able to predict SD with a good sensitivity (87.5%), specificity (54.7%), and area under the curve (AUC) (0.72, 95% CI 0.55-0.88; p = 0.0493)., Conclusions: Taken together, these findings suggest that cfDNA could serve as a potential prognostic biomarker of SD. Studies with cfDNA kinetics and its combination with other biomarkers and clinical parameters would further improve the diagnostic ability for SD.

There is no definitive predictor of dengue severity, and this has led to a very large number of unnecessary hospitalizations worldwide. Although mast cell mediators are believed to a play role in dengue severity, the lack of precise kinetic data demands further research on early predictors. We enrolled 111 patients with confirmed dengue and 85 with "other febrile illness" (OFI) in a hospital-based prospective study in Vietnam. Dengue patients were classified as level 1, 2, or 3 based on the clinical intervention received. Blood samples were collected from each patient every day (pre- and post-defervescence) and after discharge. Plasma chymase, total IgE, and dengue-specific IgE were measured. Dengue-specific IgE levels showed an increasing trend during the course of illness and remained high even at post-discharge, although no significant difference was observed among severity levels. Total IgE showed no such trend. The specific IgE/total IgE ratio (S/T ratio) remained constantly higher in level 3 patients compared to other levels, with a significant difference at some time points. The S/T ratio of acute phase samples (before defervescence) tended to increase with increasing severity (level 1 < 2 < 3), and was significantly higher in level 3 patients than in level 1 and OFI patients. As an early predictor of severity allowing level 3 patients to be distinguished from other dengue patients, the S/T ratio achieved a sensitivity of 75% and specificity of 68%. We describe the kinetic profiles of IgEs, their ratio, and chymase levels at different severity levels. The S/T ratio was found to be associated with dengue severity, suggesting that it could potentially be used as an early predictor of severity.

Background: Enterovirus A71 (EV-A71) is the major cause of severe hand, foot, and mouth disease and viral encephalitis in children across the Asia-Pacific region, including in Vietnam, which has experienced a high burden of disease in recent years. Multiple subgenogroups (C1, C4, C5, and B5) concurrently circulate in the region with a large variation in epidemic severity. The relative differences in their evolution and epidemiology were examined within Vietnam and globally., Methods: A total of 752 VP1 gene sequences were analyzed (413 generated in this study combined with 339 obtained from GenBank), collected from patients in 36 provinces in Vietnam during 2003-2013, along with epidemiological metadata. Globally representative VP1 gene datasets of subgenogroups were used to coestimate time-resolved phylogenies and relative genetic diversity to infer virus origins and regional transmission network., Results: Despite frequent virus migration between countries, the highest genetic diversity of individual subgenogroups was maintained independently for several years in specific Asian countries representing genogroup-specific sources of EV-A71 diversity., Conclusion: This study highlights a persistent transmission network of EV-A71, with specific Asian countries seeding other countries in the region and beyond, emphasizing the need for improved EV-A71 surveillance and detailed genetic and antigenic characterization., (© The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)

As of 13 July 2016, 13 countries have reported fetal Zika virus (ZIKV) infection. Here we report a case of fetal ZIKV infection that resulted from an infection originating in Vietnam.

Background: Dengue is one of the most common infectious diseases. The aim of this study was to systematically review acute disseminated encephalomyelitis (ADEM) and to represent a new case., Methodology/principal Findings: We searched for articles in nine databases for case reports, series or previous reviews reporting ADEM cases in human. We used Fisher's exact and Mann-Whitney U tests. Classification trees were used to find the predictors of the disease outcomes. We combined findings using fixed- and random-effects models. A 13-year-old girl was admitted to the hospital due to fever. She has a urinary retention. The neurological examinations revealed that she became lethargic and quadriplegic. She had upper limbs weakness and lower limbs complete paraplegia. Her status gradually improved after the treatment. She was nearly intact with the proximal part of her legs had a mild weakness in discharge. The prevalence of ADEM among dengue patients was 0.4% [95% confidence intervals (95% CI) 0.1-2.5%], all neurological disorders among dengue was 2.6% [95% CI 1.8-3.8%], and ADEM among neurological disorders was 6.8% [95% CI 3.4-13%]. The most frequent manifestation of ADEM was altered sensorium/consciousness (58%), seizures and urination problems (35%), vision problems (31%), slurred speech (23%), walk problems (15%) then ataxia (12%). There was a significant difference between cases having complete recovery or bad outcomes in the onset day of neurological manifestations being earlier and in temperature being higher in cases having bad outcomes (p-value < 0.05). This was confirmed by classification trees which included these two variables., Conclusions/significance: The prevalence of ADEM among dengue and other dengue-related neurological disorders is not too rare. The high fever of ADEM cases at admission and earlier onset day of neurological manifestations are associated with the bad outcomes.

We previously reported a new community-based mosquito control strategy that resulted in elimination of Aedes aegypti (Linn.) in 40 of 46 communes in northern and central Vietnam, and with annual recurrent total costs (direct and indirect) of only $0.28-$0.89 international dollars per person. This control strategy was extended to four provinces in southern Vietnam in Long An and Hau Giang (2004-2007) and to Long An, Ben Tre, and Vinh Long (2005-2010). In a total of 14 communes with 124,743 residents, the mean ± SD of adult female Ae. aegypti was reduced from 0.93 ± 0.62 to 0.06 ± 0.09, and the reduction of immature Ae. aegypti averaged 98.8%. By the final survey, no adults could be collected in 6 of 14 communes, and one commune, Binh Thanh, also had no immature forms. Although the community-based programs also involved community education and clean-up campaigns, the prevalence of Mesocyclops in large water storage containers > 50 liters increased from 12.77 ± 8.39 to 75.69 ± 9.17% over periods of 15-45 months. At the conclusion of the study, no confirmed dengue cases were detected in four of the five communes for which diagnostic serologic analysis was performed. The rate of progress was faster in communes that were added in stages to the program but the reason for this finding was unclear. At the completion of the formal project, sustainability funds were set up to provide each commune with the financial means to ensure that community-based dengue control activities continued.

Rabies is a progressively fatal and incurable viral encephalitis caused by a lyssavirus infection. Almost all of the 55 000 annual rabies deaths in humans result from infection with dog rabies viruses (RABV). Despite the importance of rabies for human health, little is known about the spread of RABV in dog populations, and patterns of biodiversity have only been studied in limited geographical space. To address these questions on a global scale, we sequenced 62 new isolates and performed an extensive comparative analysis of RABV gene sequence data, representing 192 isolates sampled from 55 countries. From this, we identified six clades of RABV in non-flying mammals, each of which has a distinct geographical distribution, most likely reflecting major physical barriers to gene flow. Indeed, a detailed analysis of phylogeographic structure revealed only limited viral movement among geographical localities. Using Bayesian coalescent methods we also reveal that the sampled lineages of canid RABV derive from a common ancestor that originated within the past 1500 years. Additionally, we found no evidence for either positive selection or widespread population bottlenecks during the global expansion of canid RABV. Overall, our study reveals that the stochastic processes of genetic drift and population subdivision are the most important factors shaping the global phylogeography of canid RABV.