Where 2020 saw the development and testing of vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) at an unprecedented pace, the first half of 2021 has seen vaccine rollout in many countries. In this Progress article, we provide a snapshot of ongoing vaccine efficacy studies, as well as real-world data on vaccine effectiveness and the impact of virus variants of concern. Where they have been deployed in a high proportion of the adult population, the currently approved vaccines have been extremely effective in preventing COVID-19, particularly severe disease. Nonetheless, there are still significant challenges in ensuring equitable vaccine access around the globe and lessons that can be learned for controlling this pandemic and for the next pandemic.

The spread of the virus SARS‐CoV‐2, the cause of COVID‐19 has triggered a tidal wave of vaccine development. In the first 9 months since the virus emerged over 200 vaccines have begun pre‐clinical development, 36 of which have entered clinical trials. This review will cover the platforms under assessment, the immune responses underpinning the vaccines, the results so far and the considerations for the next steps.

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Structured hydrogels showing form stability and elastic properties individually tailorable on different length scales are accessible in a one‐step process. They support cell adhesion and differentiation and display growing pore size during degradation. In vivo experiments demonstrate their efficacy in biomaterial‐induced bone regeneration, not requiring addition of cells or growth factors.

The single and triple helical organization of protein chains strongly influences the mechanical properties of gelatin-based materials. A chemical method for obtaining different degrees of helical organization in gelatin is covalent functionalization, while a physical method for achieving the same goal is the variation of the drying conditions of gelatin solutions. Here we explored how the introduction of desaminotyrosine (DAT) and desaminotyrosyl tyrosine (DATT) linked to lysine residues of gelatin influenced the kinetics and thermodynamic equilibrium of the helicalization process of single and triple helices following different drying conditions. Drying at a temperature above the helix-to-coil transition temperature of gelatin (T > T(c), called v(short)) generally resulted in gelatins with relatively lower triple helical content (X(c,t) = 1-2%) than lower temperature drying (T < T(c), called v(long)) (X(c,t) = 8-10%), where the DAT(T) functional groups generally disrupted helix formation. While different helical contents affected the thermal transition temperatures only slightly, the mechanical properties were strongly affected for swollen hydrogels (E = 4-13 kPa for samples treated by v(long) and E = 120-700 kPa for samples treated by v(short)). This study shows that side group functionalization and different drying conditions are viable options to control the helicalization and macroscopic properties of gelatin-based materials.

Introduction: There is limited real-world evidence surrounding the effectiveness of early, mild-to-moderate COVID-19 treatments following the emergence and dominance of Omicron SARS-CoV-2 subvariants. Here, characteristics and acute clinical outcomes are described for patients with COVID-19 treated with sotrovimab, nirmatrelvir/ritonavir or molnupiravir, or patients at highest risk per NHS criteria but who were untreated. Methods: Retrospective cohort study of non-hospitalised patients who received early treatment for, or were diagnosed with, COVID-19 between 1 December 2021 and 31 May 2022, using data from the Discover dataset in north-west London. Patients were included if aged ≥12 years and treated with sotrovimab, nirmatrelvir/ritonavir or molnupiravir, or were untreated but expected to be eligible for early treatment per NHS highest-risk criteria at time of diagnosis. Outcomes were reported for 28 days from COVID-19 diagnosis (index). Subgroup analyses were conducted in patients with advanced renal disease, those aged 18-64 and ≥65 years and by period of Omicron BA.1, BA.2 and BA.5 (post-hoc exploratory analysis) predominance. Results: A total of 696 patients prescribed sotrovimab, 337 prescribed nirmatrelvir/ritonavir, 470 prescribed molnupiravir and 4,044 eligible high-risk untreated patients were included. A high proportion of patients on sotrovimab had advanced renal disease (29.3%), ≥3 high-risk comorbidities (47.6%) and were aged ≥65 years (36.9%). In total, 5/696 (0.7%) patients on sotrovimab, <5/337 (0.3-1.2%) patients on nirmatrelvir/ritonavir, 10/470 (2.1%) patients on molnupiravir and 114/4,044 (2.8%) untreated patients were hospitalised with COVID-19 as the primary diagnosis. Similar results were observed across all subgroups and during Omicron subvariant periods. Conclusion: Patients who received sotrovimab appeared to show evidence of multiple comorbidities that may increase risk of severe COVID-19. Low hospitalisation rates were observed for all treated cohorts across subgroups and periods of predominant variants of concern. These descriptive results require confirmation with comparative effectiveness analyses adjusting for differences in underlying patient characteristics.

Healthcare workers (HCWs) are at high risk of COVID-19. However, data on HCWs’ knowledge, attitudes, and practices (KAP) toward COVID-19 are limited. Between September and November 2020, we conducted a questionnaire-based COVID-19 KAP survey among HCWs at three hospitals in Uganda. We used Bloom’s cut-off of ≥80% to determine sufficient knowledge, good attitude, and good practice, and multivariate Poisson regression with robust variance for statistical analysis. Of 717 HCWs invited to participate, 657 (91.6%) agreed and were enrolled. The mean age (standard deviation) of enrollees was 33.2 (10.2) years; most were clinical HCWs (64.7%) and had advanced secondary school/other higher-level education (57.8%). Overall, 83.9% had sufficient knowledge, 78.4% had a positive attitude, and 37.0% had good practices toward COVID-19. Factors associated with KAP were: Knowledge: being a clinical HCW (aRR: 1.12; 95% CI: 1.02–1.23) and previous participation in health research (aRR: 1.10; 95% CI: 1.04–1.17); Attitude: age > 35 years (aRR: 0.88; 95% CI: 0.79–0.98); Practice: being a clinical HCW (aRR: 1.91; 95% CI: 1.41–2.59). HCWs in Uganda have good knowledge and positive attitude but poor practices towards COVID-19. Differences in COVID-19 KAP between clinical and non-clinical HCWs could affect uptake of COVID-19 interventions including vaccination.

---------Molecular models of gelatin-based materials formed the basis for the knowledge-based design of a polymer system with tyrosine-derived side groups enabling  interactions and hydrogen bonds and in this way creating physical netpoints. The models were validated by comparison with experimental data. Both analyses showed the desired physical interactions of desaminotyrosine (DAT) and desaminotyrosyl tyrosine (DATT) side chains. Gelatin was functionalized with DAT and DATT at 80 mol-% of the free amino groups. The functionalized gelatins had reduced helical conformations due to sterical hinderance and interchain contacts, and systematic changes of macroscopical properties, such as a clear reduction in the degree of swelling, were observed.