Knowledge, attitudes, and practices towards COVID-19 among residents of Quang Binh, Vietnam.

INTRODUCTION: The COVID-19 pandemic is raging worldwide; the number of new cases and deaths is increasing daily. This study aims to examine the knowledge, attitudes, and practices (KAP) toward COVID-19 among residents of Quang Binh, Vietnam. METHODOLOGY: A cross-sectional study was conducted between the 1st and 10th of March 2022 in Quang Binh with 413 participants through convenience sampling. A self-designed questionnaire was used for data collection, using SPSS (IBM Corp, Armonk, NY) version 26.0 for management and analysis. RESULTS: Among the 413 participants, 80.5% of participants had good knowledge about COVID-19. Kinh people and those with a high level of education have higher odds of having good knowledge. 78.2% of participants had a positive attitude and 78.2% had good practice toward COVID-19. Knowledge-Practice scores and Attitude-Practice scores have a positive correlation. TV (65.4%) and the internet (66.6%) are the most popular channels for information about COVID-19. Common barriers for participants taking COVID-19 prevention measures were "due to the demands of life" (61%) or "due to the specificity of the work" (47.7%). CONCLUSIONS: Residents of Quang Binh have a moderate KAP towards COVID-19. Health education programs are needed to improve knowledge about COVID-19 among Quang Binh residents, with a focus on ethnic minorities and people with low levels of education.

Colorimetric Sensing with Gold Nanoparticles on Electrowetting-Based Digital Microfluidics.

Digital microfluidic (DMF) has been a unique tool for manipulating micro-droplets with high flexibility and accuracy. To extend the application of DMF for automatic and in-site detection, it is promising to introduce colorimetric sensing based on gold nanoparticles (AuNPs), which have advantages including high sensitivity, label-free, biocompatibility, and easy surface modification. However, there is still a lack of studies for investigating the movement and stability of AuNPs for in-site detection on the electrowetting-based digital microfluidics. Herein, to demonstrate the ability of DMF for colorimetric sensing with AuNPs, we investigated the electrowetting property of the AuNPs droplets on the hydrophobic interface of the DMF chip and examined the stability of the AuNPs on DMF as well as the influence of evaporation to the colorimetric sensing. As a result, we found that the electrowetting of AuNPs fits to a modified Young-Lippmann equation, which suggests that a higher voltage is required to actuate AuNPs droplets compared with actuating water droplets. Moreover, the stability of AuNPs was maintained during the processing of electrowetting. We also proved that the evaporation of droplets has a limited influence on the detections that last several minutes. Finally, a model experiment for the detection of Hg2+ was carried out with similar results to the detections in bulk solution. The proposed method can be further extended to a wide range of AuNPs-based detection for label-free, automatic, and low-cost detection of small molecules, biomarkers, and metal ions.