2) This study presents an individual-based model to simulate SARS-CoV-2 transmission and clinical outcomes in a population over time. It incorporates vaccination roll-out, immune responses to infection/vaccination, and variant emergence/properties.
3) The model was applied to investigate impacts of waning vaccine immunity and Omicron emergence in Australia in early 2022, given high vaccine uptake but low prior infection.
For a Delta resurgence, accelerating booster eligibility from 6 to 3 months post-primary vaccination ..
4) ...strongly suppressed infections and clinical burdens.
While boosters could not control Omicron spread due to immune escape, earlier boosting still maximized protection against severe outcomes if Omicron retained Delta-level severity.
5) The model framework allows flexibility to change any component (e.g. add infection history) and address policy-relevant scenarios as immunity changes over time and variants emerge.
By capturing individual immunity dynamics, it can assess impacts of variants with ..
6) ...different transmissibility and severity profiles depending on population immune landscapes.
This study informed Australia's decision to accelerate its booster program in late 2021, demonstrating how such models can directly support ...
7) ...public health decision-making during outbreaks.
This study presents a novel individual-based model framework that integrates vaccination, immunity, transmission and outcomes to project COVID-19 impacts and evaluate mitigation strategies as population immunity changes.
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2) This study characterized SARS-CoV-2 transmission patterns between Rio Grande do Sul, Brazil and neighboring regions based on genomic surveillance data from June 2020 to July 2022. Over 1,400 genomes from across Rio Grande do Sul were sequenced...
3) ...representing major Gamma, Delta, and Omicron variants. Phylogenetic analysis identified distinct clades for each variant. For Gamma, Rio Grande do Sul lineages clustered most closely with Southeast Brazil states.
2) This study analyzed pre-pandemic samples from Senegal for cross-reactive immunity to SARS-CoV-2. 23.5% of samples from 2004-05 had antibodies to SARS-CoV-2 nucleoprotein only, suggesting previous human coronavirus (hCoV) infection.
3) Over 78% of these recognized hCoV-229E or -OC43 antigens, while 95.7% bound hCoV-HKU1. 82.2% and 84.4% of paired immune cells responded to SARS-CoV-2 spike and nucleoprotein stimulation. A unique individual seroconverted to SARS-CoV-2 spike and receptor binding domain 2003-04
With increasing urbanization comes habitat destruction and alteration, resulting in the loss ...
2) ...of natural nesting and foraging habitats for wildlife, including birds (Evans et al. 2009).
In fact, supplementary feeding can increase the risk of pathogen transmission or malnutrition (Galbraith et al. 2016). tandfonline.com/doi/full/10.10…
3) Ground foragers birds engaged in ground scratching/probing behaviors have higher potential for virus exposure through nasal/oral mucosa compared to aerial feeders.
Crowded ground feeding areas (e.g. around supplemental feeders) could increase contact rates between birds...
2) In this longitudinal study in Bangladesh of 452 adults researchers found that S-antibody levels after COVID vaccination declined by 50% at 4 months and continued dropping unless boosted. mRNA vaccines generated highest antibodies and 5 months protection ...
3) ...while AstraZeneca provided longest, up to 9 months. Prior infection between doses boosted antibodies and protection. Third dose or infection re-stimulated antibody increase. Lower antibodies preceded infections.
2) The nasal cavity plays an important role in SARS-CoV-2 infection, as the virus first infects nasal epithelial cells upon exposure. Current intramuscular vaccines are limited in inducing mucosal immunity in the nasal cavity. This allows the virus to potentially spread down ..
3) ...the respiratory tract before antibodies are produced. This review discusses the structure and defensive barriers of the nasal cavity, as well as the invasion mechanisms utilized by SARS-CoV-2.