Low HBV knowledge is associated with low HBV vaccination uptake in general adult population despite incentivization of HBV vaccination.

BACKGROUND: Hepatitis B virus (HBV) vaccination in Vietnamese adults remains low and unequally distributed. We conducted a study on HBV-naïve adults living in Ho Chi Minh City, Viet Nam, to determine barriers associated with HBV vaccination uptake after removing the financial barrier by providing free coupons for HBV vaccination. METHODS: After being screened for HBsAg, anti-HBs, and anti-HBc, 284 HBV-naïve study participants aged 18 and over (i.e., negative for HBsAg, anti-HBs, and anti-HBc total) were provided free 3-dose HBV vaccine coupons. Next, study participants' receipt of 1st, 2nd, and 3rd doses of HBV vaccine was documented at a pre-specified study healthcare facility, where HBV vaccines were distributed at no cost to the participants. Upon study entry, participants answered questionnaires on sociodemographics, knowledge of HBV and HBV vaccination, and related social and behavioral factors. The proportions of three doses of HBV vaccine uptake and their confidence intervals were analyzed. Associations of HBV vaccine initiation with exposures at study entry were evaluated using modified Poisson regression. RESULTS: 98.9% (281 of 284) of study participants had complete data and were included in the analysis. The proportion of participants obtaining the 1st, 2nd, and 3rd doses of HBV vaccine was 11.7% (95% Confidence Interval [95% CI] 8.0-15.5%), 10.7% (95%CI 7.1-14.3%), and 8.9% (95%CI 5.6-12.2%), respectively. On the other hand, participants were more likely to initiate the 1st dose if they had adequate knowledge of transmission (adjusted relative risk [aRR] = 2.58, 95% CI 1.12-5.92), adequate knowledge of severity (aRR = 6.75, 95%CI 3.38-13.48), and annual health-checking seeking behavior (aRR = 2.04, 95%CI 1.07-3.87). CONCLUSION: We documented a low HBV vaccination uptake despite incentivization. However, increased vaccine initiation was associated with better HBV knowledge and annual health check-up adherence. When considering expanding HBV vaccination to the general adult population, we should appreciate that HBV knowledge is an independent predictor of vaccine uptake.

Significant gaps in hepatitis B vaccination in adults in Viet Nam: Important targets toward hepatitis B elimination by 2030.

BACKGROUND: Gaps in adult hepatitis B vaccination were undefined in Vietnam, a lower-middle-income country. To address these gaps, this study defined hepatitis B vaccine coverage in adults and its associated factors in Ho Chi Minh City (HCMC), Viet Nam. We also proposed interventional strategies, prioritizing gap identification to facilitate hepatitis B elimination by 2030 and beyond. METHOD: During 2019-2020, a multi-stage cluster serosurvey with probability proportional to size was conducted to representatively invite 20,000 adults (18 years or older) throughout HCMC for hepatitis B screening (HBsAg, anti-HBs, and anti-HBc). Serologic results defined two dependent variables: vaccine-induced immunity (i.e., isolated anti-HBs) and susceptibility (i.e., HBV naive). Associations of dependent variables with surveyed demographics, socioeconomic statuses, behaviors, and medical history at risk for hepatitis B were evaluated using weighted Poisson regression. RESULTS: The prevalence was 18.5% (95%CI, 17.3-20.0%) for vaccine-induced immunity and 37.7% (35.6-39.8%) for susceptibility. Even though analyses in the general population revealed a falling trend in vaccine-induced immunity prevalence from younger to older age groups, sensitivity analyses in the non-infected population (i.e., those who were both negative for HBsAg and anti-HBc) showed that younger age groups, especially those aged 30 to 50 years, had the lowest prevalence. Social inequalities existed in different ethnicities, residence areas, education levels, house ownership, and health insurance statuses. There was no significant association between vaccine-induced immunity or susceptibility and risky behaviors and medical histories. CONCLUSION: This study depicts a significant unmet need for hepatitis B vaccination in the general adult population in HCMC, Viet Nam. Indeed, the lack of vaccination was unevenly distributed regarding age groups, geographical areas, and socioeconomic statuses, which reveals profound social disparities. Therefore, to achieve hepatitis B elimination goals, besides the current recommendations for infants and risk-based strategies, hepatitis B vaccination should be recommended for the broader population.

Establishing baseline framework for hepatitis B virus micro-elimination in Ho Chi Minh City, Vietnam - A community-based seroprevalence study.

Background: We conducted a community-based seroprevalence study using three HBV seromarkers (HBsAg, anti-HBs, anti-HBc) in Ho Chi Minh City (HCMC), Vietnam, to (1) determine the prevalence of HBV serologic profiles; (2) document factors associated with HBV infection or susceptibility; and (3) propose strategies toward HBV elimination by 2030. Methods: During 2019-2020, we deployed a multistage cluster design with probability proportionate to size, to recruit 20,000 adults for an HBV screening and linkage to care program citywide. Screening results with interpretation, recommendations, and health education materials were returned to participants. Post-study surveys were conducted within three months to identify gaps in linkage to care. Findings: Of the 17,600 adults invited, 15,275 (86.7%) participated in the study, 14,674 (96.1%) completing all data for final analyses. The prevalence of HBsAg (+) and HBV-naïve were 7.5% and 37.7%, respectively. HBV vaccination rates were 18.7% and about 50% of HCMC population had been exposed to HBV. Of the persons with HBsAg (+), 27.1% linked to care (76% used health insurance). There were wide variations in HBsAg (+) and HBV vaccination rates between districts, risk factors, and socio-economic statuses. Interpretation: The significant disease burden of and gaps in the continuum of care highlight the need and urgency to address the HBV public health problem in Vietnam. Using three screening seromarkers that tailor interventions to the needs of HBV micro-populations could be an effective strategy to pursue HBV elimination goals. Funding: Gilead Sciences Inc; Roche Diagnostic International Ltd; Roche Diagnostics-Vietnam; Abbott Diagnostics-Vietnam; Hepatitis B Foundation; Medic MedicalCenter, Vietnam; Center of Excellence for Liver Disease in Vietnam, Johns Hopkins University School of Medicine.

Demonstration of a population-based HCV serosurvey in Ho Chi Minh City, Viet Nam: Establishing baseline prevalence of and continuum of care for HCV micro-elimination by 2030.

Background: A baseline of hepatitis C virus (HCV) burden and other HCV epidemiological profiles is necessary for HCV micro-elimination in Ho Chi Minh City (HCMC), Viet Nam. This study aimed to determine HCV exposure and prevalence of HCV viremia as well as the proportion of HCV testing and treatment uptake among participants. Methods: From 2019 to 2020, the probability proportionate to size sampling method was deployed to representatively invite approximately 20,000 adults (18 or older) throughout HCMC to free screening and linkage to care for HCV. Findings: In HCMC, the weighted prevalence of anti-HCV was 1·3% (95% CI, 1·1%-1·6%). Individuals born from 1945 to 1964 had the anti-HCV prevalence of 3·6% (95% CI, 3·0%-4·2%) and represented 40·4% of all HCV cases. There were wide variations in anti-HCV prevalence in HCMC, including variations between districts, risk factors, and socioeconomic statuses. A baseline HCV continuum of care for the city demonstrated that only 28·5% (85/298, 95%CI 23·4-33·7%) of persons with anti-HCV (+) were aware of their HCV status, with 77.6% (66/85, 95%CI 68·8-86·5%) diagnosing HCV incidentally, 82·7% (62/75, 95%CI 74·1-91·2%) initiating anti-HCV therapy, and 53.6% (30/56, 95%CI 40·5-66·6%) achieving HCV cures. Interpretation: There remains a considerable disease burden of HCV in HCMC of which a significant proportion was in the age group born between 1945 to 1964. Additionally, there were significant gaps in HCV awareness, screening, and access to care in the community in Viet Nam. Thus, future interventions must have pragmatic targets, be tailored to the local needs, and emphasise screening. Funding: This work was supported by investigator-sponsored research grants from Gilead Sciences Inc. (Grant No: IN-US-987-5382); Roche Diagnostic International Ltd. (Grant No. SUB-000196); and in-kind donations from Abbott Diagnostic Viet Nam; Hepatitis B Foundation; Medic Medical Center, Viet Nam; Johns Hopkins University School of Medicine's Center of Excellence for Liver Disease in Viet Nam; and the Board of Directors, Viet Nam Viral Hepatitis Alliance (V-VHA).

Mapping for Engagement: Setting up a Community Based Participatory Research Project to Reach Underserved Communities at Risk for Hepatitis C in Ho Chi Minh City, Vietnam.

BACKGROUND: Approximately 1. 07 million people in Vietnam are infected with hepatitis C virus (HCV). To address this epidemic, the South East Asian Research Collaborative in Hepatitis (SEARCH) launched a 600-patient cohort study and two clinical trials, both investigating shortened treatment strategies for chronic HCV infection with direct-acting antiviral drugs. We conducted ethnographic research with a subset of trial participants and found that the majority were aware of HCV infection and its implications and were motivated to seek treatment. However, people who inject drugs (PWID), and other groups at risk for HCV were under-represented, although injecting drug use is associated with high rates of HCV. MATERIAL AND METHODS: We designed a community-based participatory research (CBPR) study to engage in dialogues surrounding HCV and other community-prioritized health issues with underserved groups at risk for HCV in Ho Chi Minh City. The project consists of three phases: situation analysis, CBPR implementation, and dissemination. In this paper, we describe the results of the first phase (i.e., the situation analysis) in which we conducted desk research and organized stakeholder mapping meetings with representatives from local non-government and community-based organizations where we used participatory research methods to identify and analyze key stakeholders working with underserved populations. RESULTS: Twenty six institutions or groups working with the key underserved populations were identified. Insights about the challenges and dynamics of underserved communities were also gathered. Two working groups made up of representatives from the NGO and CBO level were formed. DISCUSSION: Using the information provided by local key stakeholders to shape the project has helped us to build solid relationships, give the groups a sense of ownership from the early stages, and made the project more context specific. These steps are not only important preliminary steps for participatory studies but also for other research that takes place within the communities.

Unmet needs in occupational health: prevention and management of viral hepatitis in healthcare workers in Ho Chi Minh City, Vietnam: a mixed-methods study.

OBJECTIVES: Vietnam is an endemic area for hepatitis B virus and hepatitis C virus infection (HBV-HCV), yet its largest city, Ho Chi Minh City (HCMC), has no comprehensive policy to educate, screen, treat and protect healthcare workers (HCWs) from viral hepatitis. We conducted a mixed-methods study to document HBV-HCV infection rates, risk factors, local barriers and opportunities for providing education, screening and medical care for HCWs. DESIGN: This mixed-methods study involved an HBV and HCV serological evaluation, knowledge, attitude and practice survey about viral hepatitis and many in-depth interviews. Descriptive statistics and thematic content analysis using inductive and deductive approaches were used. SETTING: HCMC, Vietnam. PARTICIPANTS: HCWs at risk of viral hepatitis exposure at three hospitals in HCMC. RESULTS: Of the 210 invited HCWs, 203 were enrolled. Of the 203 HCWs enrolled, 20 were hepatitis B surface antigen-positive, 1 was anti-hepatitis C antibody (anti-HCV Ab)-positive, 57 were anti-hepatitis B core Ab-positive and 152 had adequate anti-hepatitis B surface Ab (anti-HBs Ab) titre (≥10IU/mL). Only 50% of the infected HCWs reported always using gloves during a clinical activity involving handling of blood or bodily fluid. Approximately 50% of HCWs were still not vaccinated against HBV following 1 year of employment. In-depth interviews revealed two major concerns for most interviewees: the need for financial support for HBV-HCV screening and treatment in HCWs and the need for specific HBV-HCV guidelines to be independently developed. CONCLUSIONS: The high HBV infection rate in HCWs coupled with inadequate preventive occupational practices among the population in HCMC highlight the urgent needs to establish formal policy and rigorous education, screening, vaccination and treatment programmes to protect HCWs from HBV acquisition or to manage those living with chronic HBV in Vietnam.

Progressive Scale-up of HBV AND HCV Testing for Hepatitis Elimination in Vietnam.

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Pharmacokinetics and Pharmacodynamics of Intensive Antituberculosis Treatment of Tuberculous Meningitis.

The most effective antituberculosis drug treatment regimen for tuberculous meningitis is uncertain. We conducted a randomized controlled trial comparing standard treatment with a regimen intensified by rifampin 15 mg/kg and levofloxacin for the first 60 days. The intensified regimen did not improve survival or any other outcome. We therefore conducted a nested pharmacokinetic/pharmacodynamic study in 237 trial participants to define exposure-response relationships that might explain the trial results and improve future therapy. Rifampin 15 mg/kg increased plasma and cerebrospinal fluid (CSF) exposures compared with 10 mg/kg: day 14 exposure increased from 48.2 hour·mg/L (range 18.2-93.8) to 82.5 hour·mg/L (range 8.7-161.0) in plasma and from 3.5 hour·mg/L (range 1.2-9.6) to 6.0 hour·mg/L (range 0.7-15.1) in CSF. However, there was no relationship between rifampin exposure and survival. In contrast, we found that isoniazid exposure was associated with survival, with low exposure predictive of death, and was linked to a fast metabolizer phenotype. Higher doses of isoniazid should be investigated, especially in fast metabolizers.

Elevation Shift in Abies Mill. (Pinaceae) of Subtropical and Temperate China and Vietnam-Corroborative Evidence from Cytoplasmic DNA and Ecological Niche Modeling.

The "elevational shift" scenario has been proposed as a model to explain the response of cold-adapted organisms to Quaternary climatic fluctuations in Europe and North America. However, the elevational shift model has not been well-explored in eastern Asia, which is more topographically complex than the other Northern Hemisphere biogeographic regions. Here, we evaluated the role of elevational shift in the closely related firs, or Abies Mill., of subtropical and temperate China. These firs are typical alpine trees with sensitivity to climate change. We tested the elevational shift hypothesis in firs of China using phylogeographic methods and ecological niche models. Our phylogeographic analyses comprised mitochondrial and chloroplast polymorphisms surveyed across 479 individuals from 43 populations representing 11 species. M1 of the 11 mitotypes and C1 of the 25 chlorotypes were inferred as the ancestral haplotype, and they had the widest distribution. The results of our phylogeographic survey revealed multiple centers of genetic diversity in distinct geographic regions and no latitudinal trend. Moreover, our results showed range expansions for seven taxa during the last glacial (64.9-18.2 or 32.5-9.1 kya), and this was consistent with the Quaternary fossil record of Abies in China. Taken together, our findings support a historical biogeographic pattern in firs of glacial expansions, probably through corridors at lower elevation, and interglacial fragmentations, through isolation at higher elevation peaks. Therefore, Abies in China probably undergoes elevational shift in response to climate change. Facing the forecasting global warming, the risk of several critically endangered firs was further enhanced as these species would have little escape space in situ to higher altitudes. According to our ENMs, we proposed an ex situ conservation strategy in the southern Hengduan Mountains region of south western China.

Prolongation of patency of airway bypass stents with use of drug-eluting stents.

OBJECTIVE: Airway bypass by transbronchial fenestration has been shown to improve forced expiratory volume and flow in explanted emphysematous human lungs. We previously demonstrated the feasibility and safety of airway bypass stent placement in a canine model, but we found that most stents occluded within 1 week. The aim of this study was to evaluate the influence of controlled-release paclitaxel-eluting stents on prolongation of patency. METHODS: With the subject dogs under general anesthesia, suitable segmental and subsegmental bronchial wall sites were selected by direct visualization with a flexible bronchoscope. A Doppler probe was used to detect and avoid sites with adjacent blood vessels. Transbronchial passages were formed with a 25-gauge transbronchial needle-tipped catheter and dilated with a 2.5-mm balloon integrated into the needle catheter. A specifically designed expandable stainless steel stent (3 mm long x 3 mm wide) embedded in a sleeve of silicone rubber was placed within the passage and expanded until secured about the bronchial wall. Fifty control stents (no paclitaxel impregnation) and 107 paclitaxel-eluting stents were placed in 25 dogs. Animals underwent bronchoscopy at intervals to assess stent patency. RESULTS: Eight instances of minor and brief bleeding occurred during stent placement; all resolved without incident. There were no pneumothoraces or deaths associated with stent placement. No delayed complications occurred. No identifiable paclitaxel-related toxicity was observed. At 1, 4, 8, and 12 weeks, the patency rates were 10%, 0%, 0%, and 0% for control stents and 100%, 96%, 76%, and 65% for paclitaxel stents. CONCLUSION: In an animal model, the use of specifically designed paclitaxel-eluting airway bypass stents was both feasible and safe. These stents resulted in a significant prolongation of patency.