Publications by authors named "Sinead Morris"

Isolation of symptomatic infectious persons can reduce influenza transmission. However, virus shedding that occurs without symptoms will be unaffected by such measures. Identifying effective isolation strategies for influenza requires understanding the interplay between individual virus shedding and symptom presentation.

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The generation time, representing the interval between infections in primary and secondary cases, is essential for understanding and predicting the transmission dynamics of seasonal influenza, including the real-time effective reproduction number (Rt). However, comprehensive generation time estimates for seasonal influenza, especially post the 2009 influenza pandemic, are lacking. We estimated the generation time utilizing data from a 7-site case-ascertained household study in the United States over two influenza seasons, 2021/2022 and 2022/2023.

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Quantifying the kinetics with which memory T cell populations are generated and maintained is essential for identifying the determinants of the duration of immunity. The quality and persistence of circulating CD4 effector memory (TEM) and central memory (TCM) T cells in mice appear to shift with age, but it is unclear whether these changes are driven by the aging host environment, by cell age effects, or both. Here, we address these issues by combining DNA labelling methods, established fate-mapping systems, a novel reporter mouse strain, and mathematical models.

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The SARS-CoV-2 pandemic has generated a considerable number of infections and associated morbidity and mortality across the world. Recovery from these infections, combined with the onset of large-scale vaccination, have led to rapidly-changing population-level immunological landscapes. In turn, these complexities have highlighted a number of important unknowns related to the breadth and strength of immunity following recovery or vaccination.

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Quantifying the kinetics with which memory T cell populations are generated and maintained is essential for identifying the determinants of the duration of immunity. The quality and persistence of circulating CD4 effector memory (T) and central memory (T) T cells in mice appear to shift with age, but it is unclear whether these changes are driven by the aging host environment, by cell age effects, or both. Here we address these issues by combining DNA labelling methods, established fate-mapping systems, a novel reporter mouse strain, and mathematical models.

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Background: Novel influenza viruses pose a potential pandemic risk, and rapid detection of infections in humans is critical to characterizing the virus and facilitating the implementation of public health response measures.

Methods: We use a probabilistic framework to estimate the likelihood that novel influenza virus cases would be detected through testing in different community and healthcare settings (urgent care, emergency department, hospital, and intensive care unit [ICU]) while at low frequencies in the United States. Parameters were informed by data on seasonal influenza virus activity and existing testing practices.

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The purpose of this study was to evaluate the potential of microbial-enhanced for the phytoremediation of seleniferous soils. The effect of selenite (Se(IV)) and selenate (Se(VI)) on (1-100 mg.L) was examined through germination (7 d) and pot (30 d) trials.

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Article Synopsis
  • The impact of asymptomatic infections on influenza transmission was unclear before COVID-19, but the pandemic has raised new questions about their significance.
  • Experts are now reevaluating the importance of these asymptomatic infections in transmitting influenza, given the established role of asymptomatic individuals in spreading COVID-19.
  • The text highlights current knowledge on the frequency and contribution of asymptomatic influenza infections to transmission, while suggesting areas for further research to fill existing gaps.
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Background: Antiviral chemoprophylaxis is recommended for use during influenza outbreaks in nursing homes to prevent transmission and severe disease among non-ill residents. Centers for Disease Control and Prevention (CDC) guidance recommends prophylaxis be initiated for all non-ill residents once an influenza outbreak is detected and be continued for at least 14 days and until 7 days after the last laboratory-confirmed influenza case is identified. However, not all facilities strictly adhere to this guidance and the impact of such partial adherence is not fully understood.

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As the SARS-CoV-2 trajectory continues, the longer-term immuno-epidemiology of COVID-19, the dynamics of Long COVID, and the impact of escape variants are important outstanding questions. We examine these remaining uncertainties with a simple modelling framework that accounts for multiple (antigenic) exposures via infection or vaccination. If immunity (to infection or Long COVID) accumulates rapidly with the valency of exposure, we find that infection levels and the burden of Long COVID are markedly reduced in the medium term.

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Background: High-dose, adjuvanted, and recombinant influenza vaccines may offer improved effectiveness among older adults compared with standard-dose, unadjuvanted, inactivated vaccines. However, the Advisory Committee on Immunization Practices (ACIP) only recently recommended preferential use of these "higher-dose or adjuvanted" vaccines. One concern was that individuals might delay or decline vaccination if a preferred vaccine is not readily available.

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In 2019 there were 490,000 children under five living with HIV. Understanding the dynamics of HIV suppression and rebound in this age group is crucial to optimizing treatment strategies and increasing the likelihood of infants achieving and sustaining viral suppression. Here we studied data from a cohort of 122 perinatally-infected infants who initiated antiretroviral treatment (ART) early after birth and were followed for up to four years.

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Barley and maize have dominated the Irish whiskey sector, but in recent years, alternative grains have started to gain traction. Ireland has a high average wheat yield, producing grain that is high in starch but low in protein, offering the potential for use in distillation. To successfully utilise Irish-grown wheat in distillation, cultivars that are suitable to the Irish climate and give high yields of alcohol need to be identified.

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To standardise research activity and determine alcohol yield from native Irish hard wheat grain, a benchmark approach that reflects Irish industry norms is required. The goal of this study was to optimise milling parameters, grain particle size, and grain to liquid ratio towards developing a standard process. Hard wheat (Triticum avestivum cv.

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Vaccines provide powerful tools to mitigate the enormous public health and economic costs that the ongoing severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic continues to exert globally, yet vaccine distribution remains unequal among countries. To examine the potential epidemiological and evolutionary impacts of “vaccine nationalism,” we extend previous models to include simple scenarios of stockpiling between two regions. In general, when vaccines are widely available and the immunity they confer is robust, sharing doses minimizes total cases across regions.

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Immune response dynamics in coronavirus disease 2019 (COVID-19) and their severe manifestations have largely been studied in circulation. Here, we examined the relationship between immune processes in the respiratory tract and circulation through longitudinal phenotypic, transcriptomic, and cytokine profiling of paired airway and blood samples from patients with severe COVID-19 relative to heathy controls. In COVID-19 airways, T cells exhibited activated, tissue-resident, and protective profiles; higher T cell frequencies correlated with survival and younger age.

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Article Synopsis
  • Vaccine dose shortages are prompting new strategies to boost population immunity against SARS-CoV-2, focusing on the timing of second doses and its impact on infection rates and viral evolution.
  • Research indicates that while a single vaccine dose can reduce infections in the short term, the long-term effects depend on how strong that single dose immunity is compared to two doses or natural infection.
  • There’s a risk that relying solely on one dose may lead to increased chances of the virus evolving to escape the immune response, emphasizing the need for more data on immune responses and a push for global vaccination efforts.
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Article Synopsis
  • - Various strategies are being considered to enhance population immunity against Covid-19 amidst vaccine shortages and logistics issues, focusing on the impact of the timing for delivering the second dose.
  • - Research indicates that while a single vaccine dose can reduce infections in the short term, longer-term effectiveness relies on how strong and lasting the immune response is compared to full two-dose and natural immunity.
  • - The study suggests that delaying the second dose could contribute to immune escape in the virus by increasing the number of individuals with partial immunity, emphasizing the importance of monitoring vaccine responses and accelerating global vaccination efforts.
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Immune responses to respiratory viruses like SARS-CoV-2 originate and function in the lung, yet assessments of human immunity are often limited to blood. Here, we conducted longitudinal, high-dimensional profiling of paired airway and blood samples from patients with severe COVID-19, revealing immune processes in the respiratory tract linked to disease pathogenesis. Survival from severe disease was associated with increased CD4 T cells and decreased monocyte/macrophage frequencies in the airway, but not in blood.

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Article Synopsis
  • The future of the COVID-19 pandemic is influenced by how well our immune system responds to the virus, but there are still many uncertainties about this response from natural infections and vaccines.
  • Using simple epidemiological models, the researchers estimate future COVID-19 cases based on different assumptions about the effectiveness and duration of immunity from previous infections and vaccinations.
  • Their findings suggest that variations in immune responses can lead to very different pandemic outcomes, ranging from ongoing epidemics to near elimination, emphasizing the need for more detailed understanding of immune responses beyond just counting active infections.
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Background: Mathematical modeling has provided important insights into HIV infection dynamics in adults undergoing antiretroviral treatment (ART). However, much less is known about the corresponding dynamics in perinatally infected neonates initiating early ART.

Setting: From 2014 to 2017, HIV viral load (VL) was monitored in 122 perinatally infected infants identified at birth and initiating ART within a median of 2 days.

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Background: HIV/AIDS is responsible for the deaths of one million people every year. Although mathematical modeling has provided many insights into the dynamics of HIV infection, there is still a lack of accessible tools for researchers unfamiliar with modeling techniques to apply them to their own clinical data.

Results: Here we present ushr, a free and open-source R package that models the decline of HIV during antiretroviral treatment (ART) using a popular mathematical framework.

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In recent years, tissue-resident memory T cells (T) have emerged as essential components of immunological memory. Following antigenic challenge, T remain in nonlymphoid tissues and defend against re-exposure. Although accumulating evidence suggests important roles for T in mediating protective immunity, fundamental aspects of the population biology of T remain poorly understood.

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Four low-cost materials, oyster shells, pumice stone, sand and zeolite were employed as adsorbents in an adsorption batch assays investigating the removal of ammonia, phosphate and nitrate from an aqueous solution. These compounds were chosen as they represent typical compounds found in landfill leachate (LFL). Assay performance was evaluated by the Langmuir and Freundlich adsorption isotherms.

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