Background: Vietnam has the national guidelines for infection control in hospitals and it also recommends the application of WHO’s IPCAF framework to do self-evaluation of infection prevention and control (IPC) activities and plan to improve them in hospitals. Objective: Our study aimed to implement the multimodal strategy for IPC, in which our expected outcome was the practices of doctors and nurses for pediatric ventilator-associated events (Ped-VAE). Design: We used the implementation research approach with the hybrid design of quasi-experimental pre-post comparison without control group. All 16 doctors and 32 nurses at the Department of PICU were observed 3 times that practicing the IPC packages for PedVAE guided by MOH. The implementation strategies used included Plan, Restructure, Train, and Quality Management. Results: Four over six steps practised by doctors and 5/10 steps practised by nurses for PedVAE were well practised after the intervention with significantly higher proportion of right practices (p<0.001). The practices of doctors had insignificant changes between pre-post intervention, including hand hygiene (85.4% and 83.3% of right practice at pre-post intervention, respectively) and daily assessment of weaning from mechanical ventilation (54.2%-68.7%). Most unchanged practices among nurses were steps of ensuring humidification and heating of inhaled gas for in patients with artificial airway.

All practice scores of the whole steps among doctors and nurses had statistically significant increase after intervention. Our implementation strategies were highly assessed by providers (doctors and nurses) and hospital managers in terms of the its acceptibility, feasibility and sustainability. Conclusion: The implementation of multimodal strategy in IPC for pediatric ventilator-associated events is effective and acceptable and feasible for hospitals at city/province level in Vietnam. In addition with improving practices of healthcare staffs, hospitals should regularly assess and upgrade ventilators machines to ensure the effectiveness of IPC.

Introduction: Nosocomial Bloodstream infection (BSI), including central line-associated blood stream infection (CLABSI) is important causes of morbidity and mortality. There are few studies describing the epidemiology of BSI in Viet Nam. Methods: A cross-sectional descriptive study was conducted in 3 intensive care units (ICUs) of the University Medical Center (UMC), Ho Chi Minh City from 2017 to 2022. The UMC service microbiology database was accessed to identify positive blood culture specimens during the period 2017–2022. Demographic and clinical details, antimicrobial management and patient outcome information were extracted from medical and laboratory records. Results: Of the 695 unique bacterial and fungal BSI episodes identified during the study period, 232 (33.4%) were community-acquired (CA), and 463 (66.6%) hospital-acquired (HA). The rate of BSI was 11.4% (463 cases/4.069 patients), in which CLABSI accounted for 59.8%. The incidence of CLABSI was 13.2% (307 cases/2.320 catheter patients) and the incidence rate was 5.8 cases per 1.000 catheter-days. On multivariable analysis, severe underweight, patient origin, central line placed in the femoral vein, duration catheter-days were significantly associated with CLABSI. We observed that prolonged duration catheter were the main risk CLABSI with 2.7- fold for 14-28 cathter-days (OR=2.7, 95% CI 2.4-3.1), 7.3-fold for more than 28 catheter-days (OR=7.3, 95% CI 5.7-9.4). The most common organisms were Gram-negative bacteria (76.2%), with K. pneumoniae (31.4%) and A. baumannii (12%) most prevalent. Gram-negative bacteria and Candida were more likely to cause infections in patients in critical care units. In addition, patients with BSI had significantly greater ICU costs than patients with Non-BSI (422 million VND (IQR 239–680) vs 184 million VND (IQR 18–92), p <0.05) Conclusions: Our data suggest that catheter duration is an important risk factor for CLABSI in the ICU. A significant daily increase in the risk of CLABSI after 28 days may warrant CVC replacement if intravascular access is necessary beyond that period.

Introduction: Urinary tract infection (UTI) is a common healthcare-associated problem. UTI has a lower mortality prevalence than other infections, but it is at high risk of leading to sepsis and increased treatment costs. Therefore, the objective of the study is to describe the epidemiology and burden of disease and determine factors associated with healthcare-associated UTI in the intensive care units (ICUs). Methods: A cross-sectional study was conducted on 4.028 patients admitted to the ICU, Neuro Surgical ICU, and ICU - Cardiovascular Surgery Department at a teaching hospital in Ho Chi Minh City from 2017 to 2022. The study collected secondary data through electronic medical records, including age, gender, diagnosis, department, urinary catheter use, urinary catheter retention time, treatment, and urine test results. Results: The prevalence of UTI in ICUs was 4.0%, of which CAUTI accounts for the highest prevalence, with the typical pathogen being E. coli. The Neuro Surgical ICU had the highest incidence and catheter-used prevalence in ICUs. UTIs were concentrated in people over 80 years old, females, and brain diseases. The length of the hospital stay was long, and the cost of the hospital stay was unaffordable, up to hundreds of millions of VND. The study found factors associated with the prevalence of UTI, such as age, gender, department, diseases, and urinary catheters. Patients with urinary catheters have a 10.98 times higher prevalence of UTI (p < 0.001; PR = 10.98, 95% CI 4.87–24.76) compared to patients without urinary catheters. Conclusions: The results of the study demonstrated that UTI remains a burden on the healthcare system, especially in ICUs. Implementing a UTI prevention package for patients with catheters is important. Besides, it is necessary to maintain continuous training for healthcare workers to properly and timely insert, remove, and replace catheters.

Introduction: Nowadays, surgical site infection is one of the four common types of healthcare-associated infections. There are many preventive measures applied and surgical hand hygiene (SHH) is the most effective and the simplest measure. This study aimed to assess the knowledge, practices of SHH among staff and the relationship between knowledge and practice of SHH in Viet Nam. Methods: An analytical cross-sectional study was conducted at the University Medical Center (UMC) in Ho Chi Minh City in 2022. The study employed a set of pre-prepared questions for the knowledge assessment section. For the practical assessment section, the research team conducted indirect observation through cameras and filled out a monitoring checklist. The data were analyzed using Stata 13.2. Results: Of the 271 healthcare workers, surgeons had the highest proportion at 48.7%, which was 18.6 times higher than that of anesthesiologists. The majority of healthcare workers received training on SHH, accounting for a rate of 95.6%. Among the participants, the overall compliance of SHH before entering the operative room accounted for 85.6%. The percentage of correct general knowledge reached 73.8%, and there was a relationship between correct knowledge and correct practice with p < 0.01. Conclusion: Our data suggests that having correct general knowledge of SHH is a crucial factor in accurately practicing SHH. Therefore, providing training to impart accurate knowledge about SHH to healthcare staff is necessary to enhance the overall compliance rate of SHH before entering the operating room.

Background: In University Medical Center Ho Chi Minh City (UMC), shelf life of sterilized packed items has been followed by time-related principle. However, duration of sterility has not been based on strong scientific evidence. Objectives: To determine the most appropriate shelf life for sterilized products according to packaging material and sterilization methods. Methods: All the experimental and the control samples (surgical instruments and linen) were prepared by four types of packaging materials (peel pouch, nonwoven, linen, and rigid container) and three types of sterilization methods (steam, Hydrogen Peroxide, Ethylene Oxide). After sterilization, sterilized samples were stored at CSSD’s storage and tested for microbial contamination in 07 periods: after 07 days, 14 days, 01 month, 03 months, 06 months, 12 months, and 18 months. Identification of the storage environment (shelf location, temperature, and relative humidity) were recorded as the same time collected samples. Results: Positive microbial cultures were seen in 0.44% (07 samples) of 1,574 samples. Up to 18 months, no organisms was cultured from any sample of (1) autoclaved surgical instrument packages wrapped in peel pouches, nonwoven, linen, (2) Hydrogen Peroxide sterilized surgical instrument packages wrapped in nonwoven, (3) Ethylene Oxide sterilized surgical instrument packages, and (4) autoclaved linen packages wrapped in nonwoven. Organisms detected were both Gram–Positive and Gram-Negative bacteria. Just only approximately 17% control samples grew bacteria. There was no any statistically significant relationship between positive experimental samples and packaging materials, sterilization methods, or storage conditions. Conclusions: Based on results of this experiment, shelf life of sterilized packed items should be still followed by time-related principle in UMC. However, the currently shelf life can be extended to reduce unnecessary costs and increase the usage rotation.

This paper presents a novel design of quad-band rat-race couplers (RRCs) based on a modified T-shaped structure (MTSS). Two coupled lines are incorporated into the conventional dual-band T-shaped structure to create the MTSS, making it equivalent to a quarter-wavelength transmission line at four operating bands. The ABCD matrix method is applied to analyze the quad-band MTSS, deriving closed-form equations for calculating parameters of the structure. Then, a conventional RRC is separated into quarter-wavelength transmission lines, which are replaced by the proposed MTSS. To validate the design method, a quad-band RRC operating at 0.6, 1.196, 1.853, and 2.45 GHz is designed, fabricated, and tested. Simulation and experimental results demonstrate excellent agreement with theoretical prediction. The measured results show that input return loss exceeds 21.75 dB, isolation is greater than 21.6 dB, and insertion loss is less than 4.4 dB at all four operating frequencies. Phase deviations observed from the measured in-phase and out-phase responses are within 0o ± 4.6o and 180o ± 6.7o, respectively. Compared to most previously reported quad-band RRCs, the proposed circuit features a simple design and offers superior performance in isolation, return loss, and insertion loss.

Antimicrobial resistance (AMR) in intensive care units (ICUs) is a critical issue, which has been exacerbated by the coronavirus disease 2019 (COVID-19) pandemic. This study investigated AMR prevalence and its associated factors among ICU patients in two Vietnamese hospitals from January 2020 to June 2022. Electronic medical records of 1,296 patients with 2,432 non-duplicate bacterial isolates were collected in Phu Tho Hospital (Northern, rural, non-COVID-19 treatment) and 175 Hospital (Southern, urban, COVID-19 treatment centre). Antibiotic susceptibility testing was conducted using VITEK2, BD Phoenix 100, and disk diffusion methods. Logistic regression with 1,000 bootstrap resampling and cross-validation was used to examine factors linked to AMR. Results revealed Acinetobacter spp. (27.5%) as leading strains in Phu Tho Hospital, while Klebsiella spp. (28.0%) predominated in 175 Hospital, except during 2021when Acinetobacter spp. reached the peak. Alarmingly, Acinetobacter spp., Klebsiella spp., and Pseudomonas aeruginosa demonstrated the highest AMR rates and multidrug resistance rates (83.8%–95.8%) in both hospitals. Resistance to cephalosporins, carbapenems, and fluoroquinolones ranged from 75% to 100%. Significant associated factors included age, sex, location, initial admission diagnosis, and bacterial isolation month. This study highlights the urgent need for controlling AMR in ICUs during the pandemic.

Connecting individual robots to form an inter-reconfigurable system with a flexible base size enhances the ability to access and cover areas for cleaning and maintenance tasks. Given that increased configuration complexity expands the search space dimension, an optimal routing solution ensuring efficiency is essential. In this paper, we present an inter-reconfigurable multi-robot system capable of adjusting the bases of its two units, along with an optimal path planning approach for confined spaces based on a modified informed rapidly-exploring random tree algorithm by a greedy set (RIRRT*). We validate the navigation of the proposed inter-reconfigurable platform using RIRRT* for four informed dimensional search spaces as a case study in both simulated and real-world environments. The proposed path planning method for the inter-reconfigurable system outperformed conventional strategies, achieving significant reduction in both execution time and energy utilization.

Myanmar is located within an important geographic corridor of prehistoric demographic and technological exchange, yet relatively few archaeological sites have been securely dated. Here, the authors present a new radiocarbon chronology for Halin, a UNESCO-listed complex in the north-central Sagaing Division of Myanmar, which contributes to the generation of nuanced regional chronologies and to improving the temporal resolution of Southeast Asia more generally. Discussion of 94 radiocarbon determinates, together with site stratigraphy and pottery traditions, provides a chronological sequence from the early third millennium BC to the early second millennium AD. Corroboration of the beginning of this sequence would place Halin as the oldest currently dated Neolithic site in Mainland Southeast Asia and would provide support for the two-layer model of Neolithic migration.

The aim of this study is to analyse the changing patterns in the transmission of COVID-19 in relation to changes in Vietnamese governmental policies, based on epidemiological data and policy actions in a large Vietnamese province, Bac Ninh, in 2021. Data on confirmed cases from January to December 2021 were collected, together with policy documents. There were three distinct periods of the COVID-19 pandemic in Bac Ninh province during 2021. During the first period, referred to as the ‘Zero-COVID’ period (01/04–07/04/2021), there was a low population vaccination rate, with less than 25% of the population receiving its first vaccine dose. Measures implemented during this period focused on domestic movement restrictions, mask mandates, and screening efforts to control the spread of the virus. The subsequent period, referred to as the ‘Transition’ period (07/05–10/22/2021), witnessed a significant increase in population vaccination coverage, with 80% of the population receiving their first vaccine dose. During this period, several days passed without any reported COVID-19 cases in the community. The local government implemented measures to manage domestic actions and reduce the time spent in quarantine, and encouraged home quarantining for the close contacts of cases with COVID-19. Finally, the ‘New-normal’ stage (10/23–12/31/2021), during which the population vaccination coverage with a second vaccine dose increased to 70%, and most of the mandates for the prevention and control of COVID-19 were reduced. In conclusion, this study highlights the importance of governmental policies in managing and controlling the transmission of COVID-19 and provides insights for developing realistic and context-specific strategies in similar settings.

Objectives: At the onset of COVID-19, whenever SARS-CoV-2 was detected at Children’s Hospital 1 (CH1), the related department or building was closed for extensive tracing, testing, and medical isolation. This process disrupted hospital activities, reduced the efficiency of patient care, and used medical resources. To address this problem, CH1 implemented a system of grouping inpatients to color-coded areas from June to December 2021. Methods: In this retrospective study, we describe the system of grouping inpatients to color-coded areas based on SARS-CoV-2 test result at a 1,600-bed, national pediatric hospital in Ho Chi Minh City. Results: Inpatients were first separated into those with or without respiratory symptoms, and secondly to different color-coded areas based on SARS-CoV-2 test result and hospitalization length: red zone (days 1–3), orange zone (days 3–7), and green zone (day 7 onward). Prior to admission, all patients were tested with a SARS-CoV-2 rapid diagnostic test. If negative, the patient was admitted to the red zone. On days 3 and 7 of hospitalization, the patient was tested using a pooled RT-PCR method. Patients negative on day 3 were relocated to the orange zone; patients negative on day 7 were relocated to the green zone. A patient with a positive test result at any time point was transferred to a COVID-19 zone. One caregiver was allowed to stay with 1 patient with similar testing regimen. A mobile transportation team was set up to deliver food and other necessities; thus, movement was restricted and interaction was prevented among zones. After this system was implemented, COVID-19 cases were detected early, with most positive cases in the red zone (19.6%) and the orange zone (2.8%), with only 1 case in the green zone (0.7%). Conclusions: The system of grouping patients to color-coded areas helped prevent SARS-CoV-2 transmission within the hospital, allowing undisrupted operation.

Objectives: In early 2021, when the COVID-19 vaccine was scarce in Vietnam, healthcare workers (HCWs) were prioritized for vaccination due to high risk of occupational exposure. However, there is some COVID-19 vaccine hesitancy within HCW communities. Assessing COVID-19 severity among vaccinated and nonvaccinated HCWs would contribute essential information to assure people of vaccine effectiveness and reduce vaccine hesitancy. Methods: We conducted a descriptive cross-sectional study at the National Hospital for Tropical Diseases in Hanoi, Vietnam, from May to June 2021. Clinical and epidemiological data from HCWs with positive polymerase chain reaction (PCR) results were collected. The severity of symptoms were classified according to Vietnam Ministry of Health guideline (Decision no. 3416 issued  July 14, 2021) into 5 categories: asymptomatic, mild, moderate, severe, and critical conditions Results: Overall, 25 HCWs qualified for this study (14 women and 11 men), with a median age of 31 years. Among them, 3 HCWs were infected due to community exposure, and the rest were infected due to occupational exposure. Also, 3 HCWs received the Astra Zeneca vaccine before being infected with SARS-CoV-2 (one fully vaccinated with 2 doses and the other 2 had had the first dose). Categorized by the severity of infection, 28% were asymptomatic, 44% had mild symptoms, 20% had moderate symptoms, and 8% experienced severe symptoms. All 3 vaccinated HCWs showed only mild symptoms. Cough and sore throat were the main symptoms recorded (60%), followed by fever (56%). Blood test results did not show significant differences between the severe and mild COVID-19 groups. Conclusions: COVID-19 vaccination reduced the severity of COVID-19 in this small sample of HCWs. Full COVID-19 vaccination is strongly recommended for HCWs to reduce the spread of COVID-19 and to limit the number of cases with severe disease.

Objectives: SARS-CoV-2 is a novel and highly infectious virus. An effective response requires rapid training of healthcare workers (HCWs). We measured the change in knowledge related to COVID-19 and associated factors before and after training of HCWs in Vietnam. Methods: A quasi-experimental design was used to evaluate HCW knowledge related to prevention and control of SARS-CoV-2 before and after attending a 2-day training-of-trainers course. Between June and September 2020, 963 HCWs from 194 hospitals in 21 provinces received the training. HCW knowledge was assessed using a 20-item questionnaire consisting of multiple-choice questions at the beginning and closing of the training course. A participant received 1 point for each correct answer. He or she was considered to have improved knowledge the posttest score was higher than the pretest score with a score ≥15 on the posttest. We applied the McNemar test and logistic regression model to test the level of association between demographic factors and change in knowledge of COVID-19. Results: Overall, 100% of HCWs completed both the pretest and posttest. At baseline, only 14.7% scored ≥15. Following the training, 78.4% scored ≥15 and 64.3% had improved knowledge according to the predetermined definition. Questions related to the order of PPE donning and doffing and respiratory specimen collection procedures were identified as having the greatest improvement (44.6% and 60.7%, respectively). Being female (OR, 1.5; 95% CI, 1.1–2.0), having a postgraduate degree (OR, 2.5; 95% CI, 1.4–4.4), working in a nonmanager position (OR, 1.5; 95% CI, 1.1–2.1), previous contact with a COVID-19 patient (OR, 1.5; 95% CI, 1.1–2.0), and working in northern Vietnam (OR, 2.0; 95% CI, 1.4–2.6), were associated with greater knowledge improvement. Conclusions: Most HCWs demonstrated improved knowledge of COVID-19 prevention and control after attending the training. Particular groups may benefit from additional training: those who are male, leaders and managers, those who hold an undergraduate degree, and those who work in the southern provinces.

In this study, we present a comprehensive dual-band ambient radio-frequency (RF) energy harvesting system, consisting of rectenna and power management circuit, to harvest energy from 2.45 and 5.8 GHz Wi-Fi. The rectenna employs a metamaterial antenna based on a split-ring resonator, which possesses omni-directional radiation pattern at both frequencies and compact size (0.18λ × 0.25λ at 2.45 GHz). The dual-band rectifier yields the highest efficiency of 42% at 2.45 GHz and 1 dBm input power, 30% at 5.8 GHz and − 7 dBm input power. The maximum RF-DC efficiency for each band is 72% at − 5 dBm and 27% at − 2 dBm, respectively. The power management circuit, consisting of a storing capacitor and a boost converter, is integrated to produce a stable, sufficient output voltage. The energy harvesting system, with its comprehensiveness, is suitable for supplying low-power wireless sensor nodes for indoor applications.