ABSTRACT
Background: At present new epidemic has entered a stage of normalized management, but there is still sporadic distribution, public already had certain protective knowledge of coronavirus disease 2019 (COVID-19). G County of Liangshan Yi Autonomous Prefecture is located in the mountainous area of southwest Sichuan Province, which also is ethnic minorities and as national-level poverty-stricken areas, residents in the region to the migrant workers as the main economic source of personnel with high mobility. In order to ensure the resumption of work and production, the effective implementation of epidemic prevention measures has certain guiding significance for epidemic prevention and control and economic recovery. This study investigated and analyzed the status quo of villagers' attitudes and behaviors toward COVID-19 prevention and control in Liangshan Yi Autonomous Prefecture, providing evidence for COVID-19 prevention and control measures in the resumption of rural work and agricultural production. Methods: Snowball sampling was used to survey 117 villagers from an impoverished village in Liangshan Yi Autonomous Prefecture on February 10-19, 2020. A total of 120 questionnaires were collected, the recovery rate is 97.5%. Based on literature review, a self-designed questionnaire on attitudes and behaviors related to COVID-19 prevention and control was designed, the expert validity score was 0.912, and Cronbach α coefficient was 0.903. Results: The overall score for respondents' attitude toward COVID-19 prevention and control was 29.65±3.23, which was considered a good level. The total score for prevention and control behavior was 114.74±17.09, which was medium level. A statistically significant difference was found for the attitudes and behaviors of different ethnic groups toward epidemic prevention and control. Conclusions: The people in this village had a positive attitude toward epidemic prevention and control, but there was still room for improvement in prevention and control behavior. Training on hand hygiene and wearing masks outside should be strengthened, and relevant training for ethnic minorities should be further strengthened.
ABSTRACT
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) uses its S1 spike protein to bind to angiotensin-converting enzyme 2 (ACE2) on human cells in the first step of cell entry. Tryptanthrin, extracted from leaves of the indigo plant, Polygonum tinctorium, using d-limonene (17.3 µg/ml), is considered to inhibit ACE2-mediated cell entry of another type of coronavirus, HCoV-NL63. The current study examined whether this extract could inhibit the binding of the SARS-CoV-2 spike protein to ACE2. Binding was quantified as cell-bound fluorescence intensity in live cell cultures in which canine kidney MDCK cells overexpressing ACE2 were incubated with fluorescein-labeled S1 spike protein. When indigo extract, together with S1 protein, was added at 8,650x and 17,300x dilutions, fluorescence intensity decreased in a dose- and S1 extract-dependent manner, without affecting cell viability. When 4.0-nM tryptanthrin was added instead of the indigo extract, fluorescence intensity also decreased, but to a lesser degree than with indigo extract. Docking simulation analyses revealed that tryptanthrin readily bound to the receptor-binding domain of the S1 protein, and identified 2- and 7-amino acid sequences as the preferred binding sites. The indigo extract appeared to inhibit S1-ACE2 binding at high dilutions, and evidently contained other inhibitory elements as well as tryptanthrin. This extract may be useful for the prevention or treatment of SARS-CoV-2 infection.
ABSTRACT
Coronavirus disease-2019 (COVID-19) is a novel viral infectious disease that the World Health Organization (WHO) has announced to be a pandemic. This meta-analysis was aimed at providing evidence for the use of ivermectin to prevent COVID-19 among hospital workers in low-resource countries. Medical databases including African Journals online, Google Scholar, PubMed, Cochrane library, EMBASE, COVID-19 research database (WHO), Clinicaltrials.gov, and SCOPUS were searched for studies on Ivermectin as a chemoprophylactic drug against COVID-19 among hospital personnel in settings with limited resources. Preprint servers such as bioRxiv and medRxiv as well as the gray literature were also searched. Studies adjudged to be eligible were identified using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses algorithm. Statistical analyses were done using Stata version 14.3. Seven studies were selected for the meta-analysis. The total sample size was 2652. There were two randomized controlled trials and five nonrandomized studies. Some studies dosed Ivermectin daily while some dosed it weekly. However, one of the studies dosed it monthly. The studies reported variable clinical benefits. I2 statistic was 92%, and random effect model was used. The pooled odd ratio was 0.11 (95% confidence interval 0.09-0.13). This implies that 89% of the participants benefited from taking Ivermectin as a form of preexposure chemoprophylaxis. Ivermectin has a significant clinical benefit as a preventive drug against COVID-19 for hospital personnel in settings with limited resources.