Abstract Objective: To evaluate the susceptibility of S. mutans during growth as a biofilm in the presence of different concentrations of propolis. Material and Methods: Three different concentrations of ethanolic extract of propolis (10%, 5%, and 2.5%) were used to evaluate its potential to attenuate the biofilm formation of S. mutans (ATCC 25175) on microplates. A crystal violet staining method was performed to measure the optical density (OD) of the biofilm biomass after 3 h and 18 h time periods. All the experiments were performed in triplicate, and the obtained data were expressed as mean ± standard deviation. A two-tailed Student’s t-test was used to determine the different abilities of biofilm formation between the treated and control groups of the bacteria film in the presence of propolis. A p-value of <0.05 was taken as a significant value Results: The OD levels (determined using an ELISA reader) obtained after growing S. mutans as a biofilm in the presence of propolis were similar (p>0.05) to those of the control (S. mutans grown in tryptic soy broth + 1% sucrose) Conclusion: All the tested concentrations of propolis added to the growth medium did not inhibit the biofilm formation of S. mutans. Since biofilms consist of bacterial cells and extracellular matrices, we hypothesize that the extracellular matrix may have interfered with the antimicrobial properties of the tested propolis.

BACKGROUND: Triage is one of the core requirements for the provision of effective emergency care and has been shown to reduce patient mortality. However, in low- and middle-income countries this strategy is underused, under-resourced and poorly researched. OBJECTIVE: To assess the inter- and intra-rater reliability and accuracy of nurse triage ratings when using the South African Triage Scale (SATS) in an emergency department (ED) in Timergara, Pakistan. METHODS: Fifteen ED nurses assigned triage ratings to a set of 42 reference vignettes (written case reports of ED patients) under classroom conditions. Inter-rater reliability was assessed by comparing these triage ratings; intra-rater reliability was assessed by asking the nurses to re-triage 10 random vignettes from the original set of 42 vignettes and comparing these duplicate ratings. Accuracy of the nurse ratings was measured against the reference standard. RESULTS: Inter-rater reliability was substantial (intraclass correlation coefficient 0.77; 95% confidence interval (CI) 0.69 - 0.85). The intrarater agreement was also high with 87% exact agreement (95% CI 67 - 100) and 100% agreement allowing for a one-level discrepancy in triage ratings. Overall, the SATS had high specificity (97%) and moderate sensitivity (70%). Across all acuity levels the proportion of over-triage did not exceed the acceptable threshold of 30 - 50%. Under-triage was acceptable for all except emergency cases (66%). CONCLUSION: ED nurses in Pakistan can reliably use the SATS to assign triage acuity ratings. While the tool is accurate for 'very urgent' and 'routine' cases, importantly, it may under-triage 'emergency' cases requiring immediate attention. Approaches that will improve accuracy and validity are discussed.