COVID-19

  • Risk of sustained SARS‑CoV‑2 transmission in Queensland, Australia

    We used an agent-based model Covasim to assess the risk of sustained community transmission of SARSCoV-2/COVID-19 in Queensland (Australia) in the presence of high-transmission variants of the virus. The model was calibrated using the demographics, policies, and interventions implemented in the state. Then, using the calibrated model, we simulated possible epidemic trajectories that could eventuate…

  • Rural prioritization may increase the impact of COVID-19 vaccines in a representative COVAX AMC country setting due to ongoing internal migration: A modeling study

    How COVID-19 vaccine is distributed within low- and middle-income countries has received little attention outside of equity or logistical concerns but may ultimately affect campaign impact in terms of infections, severe cases, or deaths averted. In this study we examined whether subnational (urban-rural) prioritization may affect the cumulative two-year impact on disease transmission and burden…

  • The changing value of vaccines in the COVID-19 pandemic

    The Omicron wave has left a global imprinting of immunity which changes the COVID landscape. In this study, we simulate six hypothetical variants emerging over the next year and evaluate the impact of existing and improved vaccines. We base our study on South Africa’s infection- and vaccination-derived immunity. Our findings illustrate that variant-chasing vaccines will…

  • Regional differences in NPI efficacy and recommendations for Africa

    Non-pharmaceutical interventions (NPIs) remain a key component of COVID response, particularly in low- and middle-income countries (LMICs) where vaccination is limited (Padma, 2021). Much of what we know about NPI efficacy, however, comes from HIC contexts, and this knowledge is not necessarily transferrable to LMICs (Chowdhury et al., 2020). It is well-established that lockdowns have…

  • Modelling the impact of reducing control measures on the COVID-19 pandemic in a low transmission setting

    Objectives: To assess the risks associated with relaxing coronavirus disease 2019 (COVID‐19)‐related physical distancing restrictions and lockdown policies during a period of low viral transmission. Design: Network‐based viral transmission risks in households, schools, workplaces, and a variety of community spaces and activities were simulated in an agent‐based model, Covasim. Setting: The model was calibrated for…

  • Chapter 10 – Mathematical modeling as a tool for policy decision making: Applications to the COVID-19 pandemic

    The coronavirus disease 2019 (COVID-19) pandemic highlighted the importance of mathematical modeling in advising scientific bodies and informing public policy making. Modeling allows a flexible theoretical framework to be developed in which different scenarios around spread of diseases and strategies to prevent it can be explored. This work brings together perspectives on mathematical modeling of…

  • Role of masks, testing and contact tracing in preventing COVID-19 resurgences: a case study from New South Wales, Australia

    Objectives: The early stages of the COVID-19 pandemic illustrated that SARS-CoV-2, the virus that causes the disease, has the potential to spread exponentially. Therefore, as long as a substantial proportion of the population remains susceptible to infection, the potential for new epidemic waves persists even in settings with low numbers of active COVID-19 infections, unless…

  • Impact of COVID-19-related disruptions to measles, meningococcal A, and yellow fever vaccination in 10 countries

    Background: Childhood immunisation services have been disrupted by the COVID-19 pandemic. WHO recommends considering outbreak risk using epidemiological criteria when deciding whether to conduct preventive vaccination campaigns during the pandemic. Methods: We used two to three models per infection to estimate the health impact of 50% reduced routine vaccination coverage in 2020 and delay of…

  • Insights into population behavior during the COVID-19 pandemic from cell phone mobility data and manifold learning

    Understanding the complex interplay between human behavior, disease transmission and non-pharmaceutical interventions during the COVID-19 pandemic could provide valuable insights with which to focus future public health efforts. Cell phone mobility data offer a modern measurement instrument to investigate human mobility and behavior at an unprecedented scale. We investigate aggregated and anonymized mobility data, which…

  • Viral genomes reveal patterns of the SARS-CoV-2 outbreak in Washington State

    The rapid spread of SARS-CoV-2 has gravely impacted societies around the world. Outbreaks in different parts of the globe are shaped by repeated introductions of new lineages and subsequent local transmission of those lineages. Here, we sequenced 3940 SARS-CoV-2 viral genomes from Washington State to characterize how the spread of SARS-CoV-2 in Washington State (USA)…