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.

Globally, providing evidence on the economic burden of chronic obstructive pulmonary disease (COPD) is becoming essential as it assists the health authorities to efficiently allocate resources. This study aimed to summarize the literature on economic burden evidence for COPD from 1990 to 2019. This study examined the economic burden of COPD through a systematic review of studies from 1990 to 2019. A search was done in online databases, including Web of Science, PubMed/Medline, Scopus, and the Cochrane Library. After screening 12,734 studies, 43 articles that met the inclusion criteria were identified. General study information and data on direct, indirect, and intangible costs were extracted and converted to 2018 international dollars (Int$). Findings revealed that the total direct costs ranged from Int$ 52.08 (India) to Int$ 13,776.33 (Canada) across 16 studies, with drug costs rannging from Int$ 70.07 (Vietnam) to Int$ 8,706.9 (China) in 11 studies. Eight studies explored indirect costs, while one highlighted caregivers’ direct costs at approximately Int$ 1,207.8 (Greece). This study underscores the limited research on COPD caregivers’ economic burdens, particularly in developing countries, emphasizing the importance of increased research support, particularly in high-resource settings. This study provides information about the demographics and economic burden of COPD from 1990 to 2019. More strategies to reduce the frequency of hospital admissions and acute care services should be implemented to improve the quality of COPD patients’ lives and reduce the disease’s rising economic burden.

Background: Suicide continues to be a leading cause of death worldwide. Recently, more than 45,000 children in the age group of 10 to 19 years died by suicide, making it the second leading cause of death in the age group of 15 to 19, surpassed only by traffic accidents, tuberculosis, and fighting. Objective: To determine the prevalence of suicidal ideation among adolescents whose parents are separated/divorced; and to explore the factors associated with suicidal ideation and describe adverse experiences among adolescents. Methods: A cross-sectional descriptive study was conducted in 309 adolescents with separated/separated parents in Hue City. Data was collected through direct interviews using a structured questionnaire. Suicidal ideation was defined as the presence of thoughts or plans related to suicide within the last 12 months. Multivariate logistic regression was applied to identify factors associated with suicidal ideation in adolescents with separated/ separated parents. Results: The study found that 15.5% (95% CI:11.7 - 20.1) of adolescents with separated /separated parents reported experiencing suicidal thoughts, in which men accounted 8.4% (95% CI:5.6 – 11.2) and women accounted 7.1% (95% CI:4.5 - 10.6). Several factors were identified as increasing the risk of suicidal ideation, including alcohol use (OR = 3.24; 95% CI:1.42 - 7.42), hyperactivity/inattention (OR = 4.96; 95% CI:1.58 - 15.605), and a poor quality of family relationships (OR = 4.82; 95% CI:1.26 - 18.50). On the contrary, certain factors were found to reduce the risk, including being in the 14-15 age group of 14-15 (OR = 0.26; 95% CI:0.10 - 0.69) and participating in physical activity (OR = 0.44; 95% CI:0.21 – 0.94). Conclusions: The research highlights a significant percentage of adolescents with separated / divided parents who experience suicidal ideation. Therefore, it is imperative for families, schools, and society to develop comprehensive strategies to monitor and address various risky behaviours among students simultaneously.

Objective: Female sex workers (FSWs) are at high risk of human papillomavirus (HPV) infections and cervical cancer due to their high number of sexual partners. The objectives of this study were to determine the prevalence of HPV and identify risk factors for high-risk HPV infection among FSWs in Hanoi and Ho Chi Minh City (HCMC), Viet Nam. Methods: A cross-sectional study was conducted in Hanoi and HCMC between December 2017 and May 2018. We surveyed and screened 699 FSWs aged ≥18 years for HPV infection and abnormal cytology. A multivariable modified Cox regression model was used to determine risk factors for high-risk HPV infection. Results The overall prevalence of any HPV, high-risk HPV and HPV-16/18 infection in the 699 FSWs was 26.3%, 17.6% and 4.0%, respectively, and were similar in both cities. Multiple infections were identified in 127 participants (69.0%).HPV-52 was the most prevalent (7%), followed by HPV-58 (6%). Abnormal cytology was detected in 91 participants (13.0%). FSWs who are divorced (adjusted prevalence ratio [aPR]: 1.96, 95% confidence interval [CI]: 1.01–3.81), widowed (aPR: 3.26, 95% CI: 1.49–7.12) or living alone (aPR: 1.85, 95% CI: 1.01–3.39) were associated with a higher prevalence of high-risk HPV infection.

Endophytic fungi are promising sources for the production of podophyllotoxin-an important anticancer compound, replacing depleted medical plants. In this study, the endophytes associated with Dysosma difformis-an ethnomedicinal plant species were isolated to explore novel sources of podophyllotoxin. Fifty-three endophytic fungi were isolated and identified by morphological observation and ITS-based rDNA sequencing, assigning them to 27 genera in 3 divisions. Fusarium was found the most prevalent genus with a colonization frequency of 11.11%, followed by Trametes (9.26%) and Penicillium (7.41%). Phylogenetic trees were constructed for the endophytic fungi community in two collection sites, Ha Giang and Lai Chau, revealing the adaptation of the species to the specific tissues and habitats. Cytotoxic activity of endophytic fungal extracts was investigated on cancer cell lines such as SK-LU-1, HL-60, and HepG2, demonstrating strong anti-cancer activity of six isolates belonging to Penicillium, Trametes, Purpureocillium, Aspergillus, and Ganoderma with IC 50 value of lower than 10 10 µg/mL. The presence of podophyllotoxin was indicated in Penicillium, Trametes, Aspergillus and for the first time in Purpureocillium and Ganoderma via high-performance liquid chromatography, which implied them as a potential source of this anticancer compound.

Objectives: Online misinformation has reached unprecedented levels during the coronavirus disease 2019 (COVID-19) pandemic. This study analyzed the magnitude and sentiment dynamics of misinformation and unverified information about public health interventions during a COVID-19 outbreak in Da Nang, Vietnam, between July and September 2020. Methods: We analyzed user-generated online information about five public health interventions during the Da Nang outbreak. We compared the volume, source, sentiment polarity, and engagements of online posts before, during, and after the outbreak using negative binomial and logistic regression, and assessed the content validity of the 500 most influential posts. Results: Most of the 54,528 online posts included were generated during the outbreak (n = 46,035; 84.42%) and by online newspapers (n = 32,034; 58.75%). Among the 500 most influential posts, 316 (63.20%) contained genuine information, 10 (2.00%) contained misinformation, 152 (30.40%) were non-factual opinions, and 22 (4.40%) contained unverifiable information. All misinformation posts were made during the outbreak, mostly on social media, and were predominantly negative. Higher levels of engagement were observed for information that was unverifiable (incidence relative risk [IRR] = 2.83; 95% confidence interval [CI], 1.33–0.62), posted during the outbreak (before: IRR = 0.15; 95% CI, 0.07–0.35; after: IRR = 0.46; 95% CI, 0.34-0.63), and with negative sentiment (IRR = 1.84; 95% CI, 1.23–2.75). Negatively toned posts were more likely to be misinformation (odds ratio [OR] = 9.59; 95% CI, 1.20–76.70) or unverified (OR = 5.03; 95% CI, 1.66–15.24). Conclusions Misinformation and unverified information during the outbreak showed clustering, with social media being particularly affected. This indepth assessment demonstrates the value of analyzing online “infodemics” to inform public health responses.

Balanophora laxiflora Hemsl. (Balanophoraceae) is a traditional medicinal plant with a diverse array of biological activities. In our exploration of new bioactive constituents from B. laxiflora, we isolated five compounds, including a new lignan, balanophorone (5), and four known phenolic compounds (1–4). The chemical structures of these compounds were determined by extensive spectroscopic analyses, including 1D and 2D NMR, HR-ESI-MS, and CD. In addition, we evaluated the effects of each of the isolates (1–5) on the messenger RNA expression levels of tumor necrosis factor (TNF)-α and cyclooxygenase (COX)-2 in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages and cytotoxicity against MCF-7 and MDA-MB-231 breast cancer cells. Compound 2 showed significant inhibition of LPS-induced COX-2 and TNF-α expression in RAW 264.7 macrophages, while compound 4 showed moderate cytotoxicity against MCF-7 and MDA-MB-231 breast cancer cells, with IC 50 values of 18.3 and 30.7 μM, respectively. No significant effects on the viability of normal mammary epithelial cells were observed.

Balanophora laxiflora Hemsl. (Balanophoraceae) is a traditional medicinal plant with a diverse array of biological activities. In our exploration of new bioactive constituents from B. laxiflora, we isolated five compounds, including a new lignan, balanophorone (5), and four known phenolic compounds (1–4). The chemical structures of these compounds were determined by extensive spectroscopic analyses, including 1D and 2D NMR, HR-ESI-MS, and CD. In addition, we evaluated the effects of each of the isolates (1–5) on the messenger RNA expression levels of tumor necrosis factor (TNF)-α and cyclooxygenase (COX)-2 in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages and cytotoxicity against MCF-7 and MDA-MB-231 breast cancer cells. Compound 2 showed significant inhibition of LPS-induced COX-2 and TNF-α expression in RAW 264.7 macrophages, while compound 4 showed moderate cytotoxicity against MCF-7 and MDA-MB-231 breast cancer cells, with IC 50 values of 18.3 and 30.7 μM, respectively. No significant effects on the viability of normal mammary epithelial cells were observed.

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.

Objective: To investigate the osteoblastogenic activity of the ethyl acetate (EtOAc) extract of Smilax glabra Roxb roots and its major active compound astilbin. Methods: Astilbin was isolated from EtOAc extract using silica gel chromatography combined with fraction crystallization. Chemical structure of astilbin was determined by analysis of the spectroscopic data in comparison with the literature. MTT method was used to detect the toxicity. Alkaline phosphatase (ALP) activity was determined by the spectrophotometric method at 405 nm using p-nitrophenyl phosphate as a substrate. Calcium deposition was stained with alizarin red-S, distained with cetylpyridium chloride, and quantified at 562 nm. In silico model for astilbin-ALP interaction was analyzed using AutoDock 4.2.6. The changes in expression of osteoblast differentiation related genes were determined using quantitative real-time PCR. Results: Both the EtOAc extract and astilbin had no toxicity toward osteoblast MC3T3-E1 cells at 5.0, 10, 25, and 50 μg/mL. At 25 μg/ mL, they enhanced ALP activity and mineralization of osteoblasts up to 30% and 55% for the EtOAc extract and 22% and 41% for astilbin, respectively. Molecular docking analysis of astilbin-ALP interaction revealed Arg167, Asp320, His324, and His437 were key residues participating in hydrophobic interaction; meanwhile, His434 and Thr436 residues were involved in hydrogen bond formation in the active site of human tissue-nonspecific ALP. Moreover, the expression level of genes opn, col1, osx, and runx2 were up-regulated in astilbin treated samples with the fold changes as 2.2; 3.7; 4.1; 2.3, respectively at 10 μg/mL (P<0.05). Conclusions: The EtOAc extract and its major compound astilbin exhibit osteoblastogenic activity by up-regulating important markers for bone cell differentiation. It could be a new and promising osteogenic agent with dual actions for therapeutic applications.