Objective: The risk of transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from schoolchildren to their household and the protective effects of vaccination in these settings remain poorly understood. We assessed the transmission dynamics of schoolchildren with SARS-CoV-2 within their households and the protective effects of coronavirus disease (COVID-19) vaccination among household members in Viet Nam. Methods: We estimated the attack rate, vaccine effectiveness and adjusted risk ratio (aRR) of factors associated with SARS-CoV-2 transmission to household contacts of children confirmed to have COVID-19 who attended three schools in Ha Nam, Phu Tho and Thanh Hoa provinces between September and December 2021 using multivariable regression with household-level random effects. Results: This retrospective cohort study included 157 children infected with SARS-CoV-2 and their 540 household contacts. The attack rate among household contacts was 24.6% (133/540). Overall, vaccine effectiveness among household contacts was 39% (95% confidence interval [CI]: -1 to -63), higher among males than females and higher in adults aged >40 years. COVID-19 transmission was greater among female household contacts compared with males (aRR: 1.35, 95% CI: 0.94 to 1.95), although not statistically significant, and highest among those aged 19–39 years (aRR: 2.51, 95% CI: 1.50 to 4.21). Fully vaccinated household contacts had significantly lower infection risk (aRR: 0.46, 95% CI: 0.26 to 0.84). Discussion: We found substantial onward transmission of SARS-CoV-2 from schoolchildren to household members, and older people were more likely to be protected by vaccination. We recommend that schoolchildren and all household members living with schoolchildren receive at least two doses of a COVID-19 vaccine. Recognizing the role of schoolchildren in the onward transmission of COVID-19 is an important lesson learned by Viet Nam that can help not only in managing other outbreaks but also in protecting schoolchildren by predicting the progress of the outbreak and preparing for a timely response.

Background: s/Aims: Parenchymal-sparing anatomical hepatectomy (Ps–AH) based on portal ramification of the right anterior section (RAS) is a new technique to avoid unnecessarily transecting too much liver parenchyma, especially in cases of major anatomical hepatectomy. Methods: We prospectively assessed 26 patients with primary hepatic malignancies having undergone major Ps–AH based on portal ramification of the RAS from August 2018 to August 2022 (48 months). The perioperative indications, clinical data, intra-operative index, pathological postoperative specimens, postoperative complications, and follow-up results were retrospectively evaluated. Results: Among the 26 patients analyzed, there was just one case that had intrahepatic cholangiocarcinoma The preoperative level of α– Fetoprotein was 25.2 ng/mL. All cases (100%) had Child–Pugh A liver function preoperatively. The ventral/dorsal RAS was preserved in 19 and 7 patients, respectively. The mean surgical margin was 6.2 mm. The mean surgical time was 228.5 minutes, while the mean blood loss was 255 mL. In pathology, 5 cases (19.2%) had microvascular invasion, and in the group of HCC patients, 92% of all cases had moderate or poor tumor differentiation. Six cases (23.1%) of postoperative complications were graded over III according to the Clavien–Dindo system, including in three patients resistant ascites or intra-abdominal abscess that required intervention. Conclusions Parenchymal-sparing anatomical hepatectomy based on portal ramification of the RAS to achieve R0-resection was safe and effective, with favorable short-term outcomes. This technique can be used widely in clinical practice.

Background: The Covid-19 pandemic that occurred at the end of 2019, especially the fourth wave in Vietnam, has affected the world not only in terms of economy, society, and physical health but also affected the mental health of population in general and of medical students in particular. The use of different coping methods may be protective or risk factors for mental health problems. Objectives: 1. To investigate the prevalence of anxiety, stress, and depression among medical students during the Covid -19 pandemic 2. To describe several coping behavior among medical students during the pandemic. Subjects and methods: A descriptive cross-sectional study conducted on 2350 students of medicine programme range from the first year to the sixth year in the school year 2021 - 2022 at Hue University of Medicine and Pharmacy. Using the DASS-21 scale to survey anxiety, depression and stress in research subjects and a self-designed questionnaire to describe the coping methods of medical students. Results: out of 2350 sample, the prevelance of depression, anxiety, and stress was 38%, 33.2%, and 17% respectively. 13.8% had both anxiety and stress, 15.4% had both stress and depression, and 12.8% had a combination of anxiety, depression and stress. Coping behavior was commonly selected including: eating and sleeping regularly as usual (68.1%); doing exercise at home at least 5 days/week and 30 minutes/day (23.9%); 36.5% of students performed their favorite activities under appropriate conditions most of the time or often. In addition, 59.7% of students had learn new things on the internet, 4.5% of students had practiced meditation and relaxation, 2.9% of students had chosen to write a diary and things they were grateful for; 32% had still maintain contacted with friends via video calls, text messages and 34.4% had chosen to participate in volunteer activities. Conclusion: This study highlights a high rate of anxiety, stress and depression among medical students during the fouthth wave of the Covid-19 pandemic. Personal lifestyle changes and social activities were amongst the most comon coping behavior reported.

Objectives: Asymptomatic infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and test re-positivity after a negative test have raised concerns about the ability to effectively control the coronavirus disease 2019 (COVID-19) pandemic. We aimed to investigate the prevalence of COVID-19 asymptomatic and pre-symptomatic infections during the second wave of COVID-19 in Viet Nam, and to better understand the duration of SARS-CoV-2 infection and the dynamics between the evolution of clinical symptoms and SARS-CoV-2 test positivity among confirmed COVID-19 cases. Methods: We conducted a cohort analysis on the first 50 confirmed cases during the second COVID-19 wave in Viet Nam using clinical, laboratory and epidemiological data collected from 9 March to 30 April 2020. Kaplan-Meier estimates were used to assess time to clearance of SARS-CoV-2 infection, and log-rank tests were used to explore factors related to time to SARS-CoV-2 infection clearance. Results: Most cases (58%) had no typical signs or symptoms of COVID-19 at the time of diagnosis. Ten cases (20%) were re-positive for SARS-CoV-2 during infection. Eight cases (16%) experienced COVID-19 symptoms after testing negative for SARS-CoV-2. The median duration from symptom onset until clearance of infection was 14 days (range: 6–31); it was longer in re-positive and older patients and those with pre-existing conditions. Conclusion Asymptomatic and pre-symptomatic infections were common during the second wave of COVID-19 in Viet Nam. Re-positivity was frequent during hospitalization and led to a long duration of SARS-CoV-2 infection.

Ultrasonic computed tomography based on back scattering theory is the most powerful and accurate tool in ultrasound based imaging approaches because it is capable of providing quantitative information about the imaged target and detects very small targets. The duple-frequency distorted Born iterative method (DF–DBIM), which uses density information along with sound contrast for imaging, is a promising approach for imaging targets at the level of biological tissues. With two frequencies f₁ (low) and f₂ (high) through Nf₁ and Nf₂ iterations respectively, this method is used to estimate target density along with sound contrast. The implications of duple-frequency fusion for the image reconstruction quality of density information along with sound contrast based ultrasound tomography have been analyzed in this paper. In this paper, we concentrate on the selection of parameters that is supposed to be the best to improve the reconstruction quality of ultrasound tomography. When there are restraints imposed on simulated scenarios to have control of the computational cost, the iteration number Nf₁ is determined resulting in giving the best performance. The DF–DBIM is only effective if there are a moderate number of iterations, transmitters and receivers. In case that the number of transducers is either too large or too small, a result of reconstruction which is better than that of the single frequency approach is not produced by the implementation of DF–DBIM. A fixed sum N(iter) of Nf₁ and Nf₂ was given, the investigation of simulation results shows that the best value of Nf₁ is [N(iter)/2 − 1]. The error, when applying this way of choosing the parameters, will be normalized with the reduction of 56.11%, compared to use single frequency as used in the conventional DBIM method. The target density along with sound contrast is used to image targets in this paper. It is a fact that low-frequency offers fine convergence, and high-frequency offers fine spatial resolution. Wherefore, this technique can effectively expand DBIM's applicability to the problem of biological tissue reconstruction. Thanks to the usage of empirical data, this work will be further developed prior to its application in reality.
Image Processing, Computer-Assisted ; Methods ; Transducers ; Ultrasonics ; Ultrasonography

BACKGROUND: In order to provide essential scientific evidence on the population's health status and social health determinants as well as the current capacity of the health care system in Vietnam to health policy makers and managers, Vietnam Ministry of Health, Hanoi University of Public Health, Hanoi Medical University, and Ho Chi Minh University of Medicine and Pharmacy collaborated with Seoul National University (Korea) and conducted a health system survey in the Quoc Oai district (of Hanoi capital) that represented northern rural Vietnam. METHODS: The study design was a cross-sectional study. The survey covered different topics (more than 200 questions) and was administered in three separate questionnaires: 1) Basic information of all household members; 2) Household characteristics; and 3) Individual characteristics. Socio-demographic characteristics among the households and individuals were collected from 2,400 households sampled by multi-stage cluster sampling method: more than 200 questions. RESULTS: The household size of Quoc Oai was larger than the national average and there was no significant difference in gender composition. In addition, the proportions of pre-elderly, age 55–64, and elderly group (65 years old and over) were higher than the national population statistics. In this context, demographic transition has begun in Quoc Oai. CONCLUSION: This study design description provides the basic information about a baseline survey of a future prospective cohort (as a part of a collaborative project on strengthening the health system in Vietnam) to the prospective data user of this survey.
Aged ; Cohort Studies ; Cross-Sectional Studies ; Delivery of Health Care ; Family Characteristics ; Health Policy ; Humans ; Methods ; Pharmacy ; Population Characteristics ; Population Dynamics ; Prospective Studies ; Public Health ; Seoul ; Surveys and Questionnaires ; Vietnam

This article describes Viet Nam Ministry of Health’s (VMoH) activities to prepare for and respond to the threat Zika virus (ZIKV), including the adaptation of existing surveillance systems to encompass ZIKV surveillance.

Background
  The Millennium Development Goals were put forth to strengthen maternal and child health, and because infectious disease has become a trend in the world, ensuring the quality and quantity of nursing is important. We report on a survey detailing the current status of legal frameworks and qualification systems in nursing in four countries: Cambodia, Lao People’s Democratic Republic (PDR), Myanmar, and Vietnam.
Method
  We conducted a semi-structured interview with nursing administrative officers, and then we confirmed those information in their countries in 2012 and 2013. We categorized the existing nursing legal framework, nursing qualification systems, professional association and council.
Results
  The King of Cambodia stipulated to a royal decree, which was established by the nursing council. In Lao PDR, following the Law on Health Care, two nursing and midwifery related regulations were developed. The Union of Myanmar enacted the Nurse and Midwife Law. In Vietnam following the Law on Medical Examination and Treatment, two Circulars were issued by the Ministry of Health to regulate the scope of practices and norms. We report on the current situation of the qualification and registration systems for nursing of each country. In addition, the development of qualifications and regulations should be reported based on the ASEAN Mutual Recognition Agreement (MRA).
Conclusion
  We conducted a comparison of four countries to ensure the quality of nursing. A challenge for the future is compliance and dissemination of the laws and regulations that have been developed. ASEAN MRA has become a driving force for improvement of these legal systems.

Four Trichoderma strains (CH2, SH16, PQ34, and TN42) were isolated from soil samples collected from Quang Tri and Thua Thien Hue provinces in Vietnam. The strains exhibited high chitinolytic secretion. Strain PQ34 formed the largest zone of chitinase-mediated clearance (> 4 cm in diameter) in agar containing 1% (w/v) colloidal chitin. Analysis of the internal transcribed spacer regions of these strains indicated that they were Trichoderma asperellum. The molecular weights of the chitinases were approximately 42 kDa. Chitinase genes (chi42) of T. asperellum strains TN42, CH2, SH16, and PQ34 were 98~99% homologous to the ech42 gene of T. harzianum CB-Pin-01 (accession No. DQ166036). The deduced amino acid sequences of both T. asperellum strains SH16 and TN42 shared 100% similarity.
Agar ; Amino Acid Sequence ; Chitin ; Chitinase ; Colloids ; Molecular Weight ; Soil ; Sprains and Strains ; Trichoderma ; Vietnam

Background: Quality, hygiene and food safety are the pressing questions that affects the public. Objectives: To discover some remarks on the microbiological contamination of food selling on the street in Thanh Hoa city and various suitable solutions in management and deployment. Subjects and method: A cross-sectional survey on the microbiological contamination of 310 different samples of food hawking on the street of 11 communes in Thanh Hoa province. Results:310 different samples were collected in Thanh Hoa city in 2007, we found micro biological contamination is still high, the highest rate was spring roll (76,7% contamined), lowest was food prepared from fish and other fish products (43,3%). Conclusion: The contamination rate varies with different organisms. The rate of food contaminated with 2 organisms was high (91.1%).To ensure the health of the public; it is necessary to have the measures to ensure that sellers provide the public with safe and hygienic food. \r\n', u'\r\n', u'\r\n', u'
microbiological contamination of the food selling