SARS-CoV-2 Omicron Subvariants Do Not Differ Much in Binding Affinity to Human ACE2: A Molecular Dynamics Study.

The emergence of the variant of concern Omicron (B.1.1.529) of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) exacerbates the COVID-19 pandemic due to its high contagious ability. Studies have shown that the Omicron binds human ACE2 more strongly than the wild type. The prevalence of Omicron in new cases of COVID-19 promotes novel lineages with improved receptor binding affinity and immune evasion. To shed light on this open problem, in this work, we investigated the binding free energy of the receptor binding domain of the Omicron lineages BA.2, BA.2.3.20, BA.3, BA4/BA5, BA.2.75, BA.2.75.2, BA.4.6, XBB.1, XBB.1.5, BJ.1, BN.1, BQ.1.1, and CH.1.1 to human ACE2 using all-atom molecular dynamics simulation and the molecular mechanics Poisson-Boltzmann surface area method. The results show that these lineages have increased binding affinity compared to the BA.1 lineage, and BA.2.75 and BA.2.75.2 subvariants bind ACE2 more strongly than others. However, in general, the binding affinities of the Omicron lineages do not differ significantly from each other. The electrostatic force dominates over the van der Waals force in the interaction between Omicron lineages and human cells. Based on our results, we argue that viral evolution does not further improve the affinity of SARS-CoV-2 for ACE2 but may increase immune evasion.

High Prevalence of Post-Traumatic Stress Disorder and Psychological Distress Among Healthcare Workers in COVID-19 Field Hospitals: A Cross-Sectional Study from Vietnam.

Objective: To evaluate the prevalence of post-traumatic stress disorder (PTSD) and other psychological disturbances in the Vietnamese healthcare workers (HCWs) at COVID-19 field hospitals. Methods: A cross-sectional study was conducted using the Impact of Event Scale-Revised (IES-R) to measure PTSD and the Depression Anxiety Stress scale (DASS) to measure other psychological disturbances. The anxiety about COVID-19 was evaluated by the fear of COVID-19 (FOC) scale. A self-developed questionnaire was used to assess work conditions and HCW's major concerns and preparedness. Ordinal logistic regression was used to identify factors associated with the severity of PTSD. A structural modeling equation (SEM) model was fitted to examine the correlation between PTSD and other psychological disturbances. Results: A total of 542 HCWs participated in this study. The prevalence of PTSD was 21.2%, most cases were mild. In the ordinal logistic regression analysis, a history of mental illness, poor preparedness, working in a condition with poor resources, a greater number of concerns, and greater fear of COVID-19 were independently associated with higher severity of PTSD. The prevalence of depression, anxiety, and stress was 46.8%, 38.3%, and 60.2, respectively. In the SEM model, PTSD and psychological disturbances had a strong correlation (standardized covariance 0.86). Conclusion: The prevalence of PTSD and other psychological disturbances was alarmingly high among HCWs who worked at COVID-19 field hospitals. The reported associated factors can be useful for policymakers and health authorities in the preparation for future pandemics.

Clinical characteristics and mortality risk among critically ill patients with COVID-19 owing to the B.1.617.2 (Delta) variant in Vietnam: A retrospective observational study.

BACKGROUND: SARS-CoV-2 Delta variant caused a large number of COVID-19 cases in many countries, including Vietnam. Understanding mortality risk factors is crucial for the clinical management of severe COVID-19. METHODS: We conducted a retrospective study at an intensive care center in Ho Chi Minh City that urgently built by Bach Mai Hospital during the COVID-19 outbreak in Vietnam, when the Delta variant predominated. Participants were laboratory-confirmed patients with SARS-CoV-2 infection, admitted in August 2021. Data on patients' demographic and clinical characteristics, radiographic and laboratory findings, treatment, and clinical time course were compared between survivors and non-survivors. Risk factors to mortality were assessed using logistic regression. RESULTS: Among 504 eligible COVID-19 patients, case fatality was 52.2%. Unvaccinated patients accounted for 61.2% of non-survivors and 43.6% of survivors (p < 0.001). The time from onset to hospital admission was 8 days in non-survivors and 7 days in survivors (p = 0.004). Among non-survivors, 90.2% developed acute respiratory distress syndrome (ARDS). Oxygen therapy was administered for all patients, but antiviral agent was given to 51.7% of non-survivors. 54.2% of non-survivors tested positive for the bacterial infection using blood culture. The risk factors for mortality were diabetes mellitus, respiration rate, oxygen saturation, vaccination status, time from onset to admission, and older age. CONCLUSIONS: Critical patients with COVID-19 owing to the Delta variant in Vietnam had delayed hospital admission, leading to ARDS and death. Early availability of vaccines and preventing bacterial infections are crucial for reducing mortality of COVID-19, especially in low- and middle-income countries.

Selection of Non-vitamin K Antagonist Oral Anticoagulant for Stroke Prevention in Atrial Fibrillation Based on Patient Profile: Perspectives from Vietnamese Experts. Part 2.

Part 1 of this review provided an overview of AF in Vietnam, with a particular focus on primary and secondary stroke prevention. Part 2 explores the management of AF in special, high-risk and clinically common patient populations, including those with renal impairment, diabetes, the elderly, and those with coronary artery disease. Furthermore, Part 2 addresses the challenges posed by patients with AF who have a bioprosthetic valve, a group situated in a grey area of consideration. Managing AF in these patient groups presents unique clinical challenges that require careful consideration. Physicians are tasked with addressing specific clinical questions to identify the optimal anticoagulation strategy for each individual. To inform these decisions, subgroup analyses from pivotal studies are presented alongside real-world data derived from clinical practice. By synthesising available information and considering the nuanced clinical context, the aim is to provide informed perspectives that align with current medical knowledge and contribute to the enhancement of patient care in these challenging scenarios.

Selection of Non-vitamin K Antagonist Oral Anticoagulant for Stroke Prevention in Atrial Fibrillation Based on Patient Profile: Perspectives from Vietnamese Experts. Part 1.

In Asia, especially Vietnam, AF is a common arrhythmia and is linked to a higher risk of stroke and systemic embolism. Anticoagulation therapy for stroke prevention in AF patients can result in bleeding complications. To effectively manage AF, adopting appropriate anticoagulation and addressing modifiable risk factors are crucial. Vietnamese clinicians are particularly interested in non-vitamin K antagonist oral anticoagulants (NOACs), a recent development in AF treatment. However, the lack of head-to-head trials comparing NOACs makes selecting a specific NOAC challenging. This review aims to provide a comprehensive overview of the available clinical evidence on NOACs for stroke prevention in AF to assist clinicians in making informed decisions and improving treatment outcomes in patients with AF. The first part of this review will present the current landscape of AF in Vietnam, focusing on AF prevalence and highlighting gaps in clinical practice. Furthermore, this part extensively discusses the anticoagulation strategy for both primary and secondary stroke prevention in AF.

Repurposing the Antiemetic Metoclopramide as an Antiviral Against Dengue Virus Infection in Neuronal Cells.

Dengue virus (DENV) is transmitted by Aedes mosquitoes to humans and is a threat worldwide. No effective new drugs have been used for anti-dengue treatment, and repurposing drugs is an alternative approach to treat this condition. Dopamine 2 receptor (D2R) is a host receptor positively associated with DENV infection. Metoclopramide (MCP), a D2R antagonist clinically used to control vomiting and nausea in patients with DENV infection, was putatively examined for inhibition of DENV infection by targeting D2R. In the mouse neural cell line Neuro-2a with D2R expression, a plaque assay demonstrated the antiviral efficacy of MCP treatment. However, in the cell line BHK-21, which did not express D2R, MCP treatment caused no further inhibition of DENV infection. Either MCP treatment or exogenous administration of a neutralizing D2R antibody blocked DENV binding. Treatment with MCP also reduced DENV dsRNA replication and DENV-induced neuronal cell cytotoxicity in vitro. An in vivo study demonstrated the antiviral effect of MCP against DENV-induced CNS neuropathy and mortality. These results showed that repurposing the D2R-targeting antiemetic MCP is a potential therapeutic strategy against DENV infection.

Acute febrile myalgia in Vietnam due to trichinellosis following the consumption of raw pork.

Trichinellosis outbreaks occur occasionally in Vietnam following the consumption of undercooked pork. Diagnosing trichinella can be problematic because fever and myalgia are nonspecific, and diagnosis may be delayed. We describe 5 Vietnamese patients in whom trichinellosis was diagnosed after several weeks of illness.

Streptococcus suis, an important cause of adult bacterial meningitis in northern Vietnam.

BACKGROUND: Streptococcus suis can cause severe systemic infection in adults exposed to infected pigs or after consumption of undercooked pig products. S. suis is often misdiagnosed, due to lack of awareness and improper testing. Here we report the first fifty cases diagnosed with S. suis infection in northern Viet Nam. METHODOLOGY/PRINCIPAL FINDINGS: In 2007, diagnostics for S. suis were set up at a national hospital in Hanoi. That year there were 43 S. suis positive cerebrospinal fluid samples, of which S. suis could be cultured in 32 cases and 11 cases were only positive by PCR. Seven patients were blood culture positive for S. suis but CSF culture and PCR negative; making a total of 50 patients with laboratory confirmed S. suis infection in 2007. The number of S. suis cases peaked during the warmer months. CONCLUSIONS/SIGNIFICANCE: S. suis was commonly diagnosed as a cause of bacterial meningitis in adults in northern Viet Nam. In countries where there is intense and widespread exposure of humans to pigs, S. suis can be an important human pathogen.