Background and aims Although vaccines are considered the most effective and fundamental therapeutic tools for consistently preventing the COVID-19 disease, worldwide vaccine hesitancy has become a widespread public health issue for successful immunization. The aim of this review was to identify an up-to-date and concise assessment of potential factors influencing COVID-19 vaccine acceptance and refusal intention, and to outline the key message in order to organize these factors according to country count. Methods A systematic search of the peer-reviewed literature articles indexed in reputable databases, mainly Pub Med (MEDLINE), Elsevier, Science Direct, and Scopus, was performed between21stJune 2021 and10th July 2021. After obtaining the results via careful screening using a PRISMA flow diagram, 47 peer-reviewed articles met the inclusion criteria and formed the basic structure of the review. Results In total, 11 potential factors were identified, of which the greatest number of articles (n = 28) reported “safety” (34.46%; 95% CI 25.05─43.87) as the overarching consideration, while “side effects” (38.73%; 95% CI 28.14─49.32) was reported by 22 articles, which was the next common factor. Other potential factors such as “effectiveness” were identified in 19 articles (29.98%; 95% CI 17.09─41.67), followed by “trust” (n = 15 studies; 27.91%; 95% CI 17.1─38.73),“information sufficiency”(n = 12; 34.46%; 95% CI 35.87─63.07),“efficacy”(n = 8; 28.73%; 95% CI 9.72─47.74), “conspiracy beliefs” (n = 8; 14.30%; 95% CI 7.97─20.63),“social influence” (n = 6; 42.11%; 95% CI 14.01─70.21), “political roles” (n = 4; 16.75%; 95% CI 5.34─28.16), “vaccine mandated” (n = 4; 51.20%; 95% CI 20.25─82.15), and “fear and anxiety” (n = 3; 8.73%; 95% CI 0.59─18.05). The findings for country-specific influential vaccination factors revealed that, “safety” was recognized mostly (n = 14) in Asian continents (32.45%; 95% CI 19.60─45.31), followed by the United States (n = 6; 33.33%; 95% CI12.68─53.98). “Side effects” was identified from studies in Asia and Europe (n = 6; 35.78%; 95% CI 16.79─54.77 and 16.93%; 95% CI 4.70─28.08, respectively), followed by Africa (n = 4; 74.60%, 95% CI 58.08─91.11); however, public response to “effectiveness” was found in the greatest (n = 7) number of studies in Asian countries (44.84%; 95% CI 25─64.68), followed by the United States (n = 6; 16.68%, 95% CI 8.47─24.89). In Europe, “trust” (n = 5) appeared as a critical predictor (24.94%; 95% CI 2.32─47.56). “Information sufficiency” was identified mostly (n = 4) in articles from the United States (51.53%; 95% CI = 14.12─88.74), followed by Asia (n = 3; 40%; 95% CI 27.01─52.99). More concerns was observed relating to “efficacy” and “conspiracy beliefs” in Asian countries (n = 3; 27.03%; 95% CI 10.35─43.71 and 18.55%; 95% CI 8.67─28.43, respectively). The impact of “social influence” on making a rapid vaccination decision was high in Europe (n = 3; 23.85%, 95% CI -18.48─66.18), followed by the United States (n = 2; 74.85%). Finally, “political roles” and “vaccine-mandated” were important concerns in the United States. Conclusions The prevailing factors responsible for COVID-19 vaccine acceptance and hesitancy varied globally; however, the global COVID-19 vaccine acceptance relies on several common factors related to psychological and, societal aspect, and the vaccine itself. People would connect with informative and effective messaging that clarifies the safety, side effects, and effectiveness of prospective COVID-19 vaccines, which would foster vaccine confidence and encourage people to be vaccinated willingly.

BackgroundAntioxidant compounds like phenols and flavonoids scavenge free radicals and thus inhibit the oxidative mechanisms that lead to control degenerative and other diseases. The aim of this study was to investigate the antioxidant activity in vitro, total phenolic and flavonoid contents in ethanol extracts and fractions of Crescentia cujete leaves and stem bark.MethodsCrescentia cujete leaves and bark crude ethanol extract (CEE) and their partitionates petroleum ether (PEF), chloroform (CHF), ethyl acetate (EAF) and aqueous (AQF) were firstly prepared. Different established testing methods, such as 1, 1-diphenyl-2-picryl hydrazyl (DPPH) radical, ferric reducing power (FRP), and total antioxidant capacity (TAC) assays were used to detect the antioxidant activity. Further, the total yield, total phenolic (TPC) and total flavonoid contents (TFC) of CEE and all the fractions were determined. Ethanol extracts of both leaves and stem bark were also subjected to preliminary phytochemical screening to detect the presence of secondary metabolites, using standard phytochemical methods (Thin layer chromatography and spray reagents).ResultsPhytochemical screening of crude ethanol extract of both leaves and stem bark revealed the presence of steroids, flavonoids, saponins, tannins, glycosides and terpenoids. All the fractions and CEE of leaves and bark exhibited antioxidant activities, however, EAF of leaves showing the highest antioxidant activity based on the results of DPPH, FRP and TAC assay tests. The above fraction has shown the significant DPPH scavenging activity (IC50 = 8.78 μg/ml) when compared with standard ascorbic acid (IC50 =7.68 μg/ml). The TAC and FRP activities increased with increasing crude extract/fractions content. The TPC (371.23 ± 15.77 mg GAE/g extract) and TFC (144.64 ± 5.82 mg QE/g extract) of EAF of leaves were found significantly higher as compared to other solvent fractions for both leaves and bark. TPC were highly correlated with the antioxidant activity (R2 = 0.9268 and 0.8515 in DPPH test for leaves and bark, respectively).ConclusionThe results of the study show that leaves of C. cujete possesses significant free radical scavenging properties compared with stem bark and a clear correlation exists between the antioxidant activity and phenolic content.

BackgroundResearch on natural products has gained a wide popularity due to the potential of discovering active compounds. The antioxidant properties contained in plants have been proposed as one of the mechanisms for the observed beneficial effect. Therefore, the present study investigated the antioxidant activity and total phenolic contents of various solvent extracts of Albizia procera leaves.MethodsAntioxidant activity of the methanol extract and its derived fractions petroleum ether (APP), carbon tetrachloride (APC), dichloromethane (APD), ethyl acetate (APE), and residual aqueous fraction (APA) of the leaves of Albizia procera was performed by in vitro chemical analyses. Total phenolic content of the APM and other five fractions were also determined. APM and its derived fractions were also subjected to preliminary phytochemical screening test for various constituents.ResultsPhytochemical screening revealed the presence of saponins, steroids, tannins, glycosides and flavonoids in the extracts. Amongst the extracts, APE showed the highest total phenolic content (449.18 ± 18.41mg of gallic acid equivalent/g of extract). In DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging test, the IC50 value of APM, APP, APC, APD, APE and APA was 43.43, 63.60, 166.18, 41.15, 11.79, and 63.06 μg/mL, respectively. Therefore, among the APM and its derived fractions, APE showed the highest antioxidant activity which is comparable to that of standard ascorbic acid (AA) (IC50 10.12 μg/mL). The total antioxidant capacity was found to be varied in different fractions. The reducing activity on ferrous ion was ranked as APE > APD > APM > APA > APC.ConclusionThe above evidences suggest that APE of A. procera leaf is a potential source of natural antioxidant and can be used to prevent diseases associated with free radicals.

BackgroundCaesalpinia bonducella is an important medicinal plant for its traditional uses against different types of diseases. Therefore, the present study investigated the antimicrobial, antidiarrhoeal, and cytotoxic activities of the methanol extract and ethyl acetate, chloroform, and petroleum ether (pet. ether) fractions of C. bonducella leaves.MethodsThe antibacterial potentialities of methanol extract and its fractions of C. bonducella leaves were investigated by the disc diffusion method against four gram-positive and five gram-negative bacteria at 300, 500 and 800 μg/disc. Kanamycin (30 μg/disc) was used as the standard drug. Antidiarrhoeal activities of leaf extracts were evaluated at two doses (200 and 400 mg/kg) and compared with loperamide in a castor oil-induced diarrhoeal model in rat. The fractions were subjected to a brine shrimp lethality test to evaluate their cytotoxicity.ResultsThe methanol extract and other three fractions exhibited better activities at higher concentrations. Amongst, the chloroform fraction showed maximum activity at all three concentrations (300, 500, and 800 μg/disc) against almost all bacteria. S. aureus and P. aeruginosa showed better sensitivities to all extracts at all three concentrations excluding the pet. ether fraction. Bacillus megaterium and Klebsiella spp. were two bacteria amongst nine that showed lowest sensitivity to the extracts. Maximum zone of inhibition (25-mm) was obtained by the methanol extract at an 800 μg/disc concentration against S. aureus. In the antidiarrhoeal test, all fractions exhibited dose-dependent actions, which were statistically significant (p < 0.05). Ethyl acetate fraction exerted maximum inhibition (51.11%) against defecation, whereas 57.75% inhibition was obtained for loperamide. Moderate cytotoxicity was found for the methanol extract and its three fractions compared with the standard drug vincristine sulfate in the brine shrimp bioassay. In the present study, the LC50 values of the methanol crude extract and ethyl acetate, chloroform, pet. ether fractions and vincristine sulfate were 223.87, 281.84, 112.2, 199.53, and 12.59 μg/mL, respectively. Therefore, the ethyl acetate fraction showed maximum cytotoxicity, whereas minimum cytotoxicity was observed for the chloroform fraction.ConclusionThe present study revealed that the ethyl acetate fraction of the C. bonducella leaves has significant antidiarrhoeal properties. The methanol extract and other three fractions of the C. bonducella leaves possess potent antibacterial activities along with moderate cytotoxicities that may lead to new drug development.

Background: Examining the prevalence of coronavirus disease (COVID-19) vaccine hesitancy and understanding what motivates students to accept or reject a newly promoted vaccine has the potential in preventing rapid spread of infection and optimizing country-wide mass vaccination programs. This systematic review aimed to examine global COVID-19 vaccine hesitancy among students, and to identify an up-to-date and concise assessment of most common factors influencing vaccine acceptance and hesitancy around the world. Methods: A systematic search of peer-reviewed literatures indexed in reputable databases was performed. After obtaining the results via screening using PRISMA flow diagram, a total of 35 articles met the inclusion criteria and formed the basic structure of the study objectives. Results: The results revealed that, the worldwide pooled COVID-19 vaccine hesitancy rate was (x̅%)=29.8% (95% CI 23.37–36.23) among students. According to the country count assessment, the pooled vaccine hesitancy has been found to be ups and downs across the countries around the world such as  (x̅%)=32% (95% CI 20.04–43.97) in Asia, (x̅%)=(28.11%, 95% CI 18.83–37.40) in the United States, (x̅%)=15.59% (95% CI 8.23–22.95) in Europe, (x̅%)=55.93% (95% CI 40.31–71.55) in Africa, (x̅%)=20.4% in North America, and (x̅%)=22.5% in multi-ethnic areas in the reported student’s COVID-19 vaccine hesitancy. In total, 10 key factors were identified. “Side effect” 45.41% (95% CI 29.68–61.14), “safety” 42.27% (95% CI 27.50–57.04), and “trust” 44.95%, (95% CI 26.51–63.39) were the overarching concerns in making students' vaccination decisions. Conclusions: The prevalence of COVID-19 vaccine hesitancy varied among the students; however, vaccine acceptance or refusal relies on several socio-psychological, societal, and vaccine related factors. This study helps the vaccine policy-makers and health stakeholders gain a better understanding of COVID-19 vaccination drive and design the vaccine promotion strategies. Health educational interventions could be the most preferred approach to improve student’s adherence and knowledge about the COVID-19 vaccination consequences.

Background: In the wake of COVID-19 prevention, a growing attention has been devoted to administering vaccines among various sub-group populations including community health care providers. As a community health worker pharmacists and pharmacy students played a crucial role in patient-centered services for managing COVID-19. Examining pharmacy students’ vaccine acceptance intent has great potential in understanding how pharmacists’ perception impacts community people. This study investigated COVID-19 vaccine acceptance among pharmacy students in Bangladesh and identified the potential factors associated with their vaccine acceptance and hesitancy. Methods: An anonymous questionnaire was deployed online using Google forms in English and conveniently sent to 1190 pharmacy students at different universities between 15th October 2021 and 15th December 2021. The convenience sampling consisted of 1034 student pharmacists (response rate 86.9%) who participated in this study. Binary logistic regressions and Chi-squared test were used for rationalizing the study objectives. Results: The pooled COVID-19 vaccine acceptance rate was 908 (87.8%; 95% CI 85.8─87.8) among student pharmacists while 29.6% (95% CI 25.4─33.9) admitted the willingness to pay (WTP) for a COVID-19 vaccine. Out of 12 vital predictive factors, “safety,” “efficacy,” and “trust” had the strongest significant and positive association with vaccine acceptance (p=0.000). The logistic analysis also revealed that “communication” and “information sufficiency” had a significant positive association with vaccine acceptance (p=0.035 and 0.038, respectively) among student pharmacists. Although the odds of accepting the COVID-19 vaccine were found to be 1.1; an insignificant association between gender and vaccine acceptance was observed in the Chi-squared test. Conclusions: The prevalence of COVID-19 vaccine apprehension will reduce if vaccine-related information becomes more publicly available. Ensuring easy access to scientific information with evidence-based and tailored communication would enhance vaccine acceptance among pharmacy students. Implementation of multidisciplinary educational intervention would support the health care students to achieve adequate knowledge on vaccination consequences.

BackgroundTribolium castaneum (Herbst) is a harmful pest of stored grain and flour-based products in tropical and subtropical region. In the present study, rhizome of Drynaria quercifolia (J. Smith) was evaluated for pesticidal and pest repellency activities against T. castaneum, using surface film method and filter paper disc method, respectively. In addition, activity of the isolated compound 3,4-dihydroxybenzoic acid was evaluated against the pest.ResultsChloroform soluble fraction of ethanol extract of rhizome of D. quercifolia showed significant pesticidal activity at doses 0.88 to 1.77 mg/cm2 and significant pest repellency activity at doses 0.94 to 0.23 mg/cm2. No pesticidal and pest repellency activity was found for petroleum ether, ethyl acetate and methanol soluble fractions of ethanol extract as well as for 3,4-dihydroxybenzoic acid.ConclusionConsidering our findings it can be concluded that chloroform soluble fraction of rhizome of D. quercifolia is useful in controlling T. castaneum of stored grain and flour-based products.Electronic supplementary materialThe online version of this article (doi:10.1186/0717-6287-47-51) contains supplementary material, which is available to authorized users.

This study investigated COVID-19 vaccine acceptance, and compared the potential factors influencing vaccine acceptance and hesitancy between public university (PuU) and private university (PrU) students in Bangladesh. An anonymous, self-administered questionnaire was sent to 640 PuU and 660 PrU students in Google Form between 25th September and 22nd November 2021, which resulted in the participation of 1034 (461 PuU vs. 573 PrU) respondents (response rate: 72.03% vs. 86.81%). The pooled vaccine acceptance rates among PuU and PrU students were almost similar (88.1%, 95% CI 85.1─91.1 vs. 87.6%, 95% CI 84.6─90.6). Employing binary logistic regression to assess the association between various potential factors and vaccine acceptance, the study revealed that out of 10 predictors, "safety" and "efficacy" had highly significant positive associations with vaccine acceptance in both cohorts (p=0.000 ,p=0.005). "Political roles" was found to have varied effects─ a significant (p=0.02) negative and a significant positive (p=0.002) association with vaccine acceptance in PuU and PrU students, respectively.Additionally, "communication" (p=0.003) and "trust" (p=0.01) were found to have significant positive associations in PrU students while "rumors" (p=0.03) had negative association in PuU students. The odds of accepting the COVID-19 vaccine were 1.5 vs. 0.9 in PuU and PrU students. Although chi-square analysis did not show any significant association between gender and vaccine acceptance, discrepancies were found in the factors that potentially affect vaccine uptake decision between PuU and PrU students.COVID-19 vaccine uptake may be improved if vaccine-related information becomes available and is communicated to large numbers of people effectively. The implementation of multidisciplinary interventional educational programs may also be considered as a preferred approach to improve student's engagement in pandemic awareness and vaccine readiness.