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  • Journal article
    Wariri O, Utazi CE, Okomo U, Dotse-Gborgbortsi W, Sogur M, Fofana S, Murray KA, Grundy C, Kampmann Bet al., 2025,

    Multi-level determinants of timely routine childhood vaccinations in The Gambia: Findings from a nationwide analysis

    , Vaccine, Vol: 43, ISSN: 0264-410X

    Introduction: Achieving the ambitious goals of the Immunisation Agenda 2030 (IA2030) requires a deeper understanding of factors influencing under-vaccination, including timely vaccination. This study investigates the demand- and supply-side determinants influencing the timely uptake of key childhood vaccines scheduled throughout the first year of life in The Gambia. Methods: We used two nationally-representative datasets: the 2019–20 Gambian Demographic and Health Survey and the 2019 national immunisation facility mapping. Using Bayesian multi-level binary logistic regression models, we identified key factors significantly associated with timely vaccination for five key vaccines: birth dose of hepatitis-B (HepB0), first, second, and third doses of the pentavalent vaccine (Penta1, Penta2, Penta3), and first-dose of measles-containing vaccine (MCV1) in children aged 12–35 months. We report the adjusted Odds Ratios (aORs) and 95 % Credible Intervals (95 % CIs) in each case. Results: We found that demand-side factors, such as ethnicity, household wealth status, maternal education, maternal parity, and the duration of the household's residency in its current location, were the most common drivers of timely childhood vaccination. However, supply-side factors such as travel time to the nearest immunisation clinic, availability of cold-storage and staffing numbers in the nearest immunisation clinic were also significant determinants. Furthermore, the determinants varied across specific vaccines and the timing of doses. For example, delivery in a health facility (aOR = 1.58, 95 %CI: 1.02–2.53), living less than 30 min (aOR = 2.11, 95 %CI: 1.2–8.84) and living between 30 and 60 min (aOR = 3.68, 95 %CI: 1.1–14.99) from a fixed-immunisation clinic was associated with timely HepB0, a time-sensitive vaccine that must be administered within 24 h of birth. On the other hand, children who received Penta1 and Penta2 on time were three- to five-fold more

  • Journal article
    Paschoalotto MAC, Cima J, Costa E, Valente de Almeida S, Gomes da Costa J, Santos JV, Passador CS, Passador JL, Barros PPet al., 2024,

    Politics and confidence toward the COVID-19 vaccination: A Brazilian cross-sectional study.

    , Hum Vaccin Immunother, Vol: 20

    This study has the aim of assessing the Brazilian perceptions, influencing factors and political positioning on the confidence concerning COVID-19 vaccination. To achieve the objective, the methods rely on a cross-sectional survey of Brazilian citizens, distributed through different social networks. The sample is composed of 1,670 valid responses, collected from almost all Brazilian states and state capitals. To analyze the data and give a clear view of the variables' relationship, the study used bivariate and comparative graphs. Results show a higher level of confidence in vaccines from Pfizer and AstraZeneca, while the lower level of confidence is associated with vaccines from Sinopharm and Sputinik5. Vaccine efficacy is the most significant influencing factor that helps in the decision to get vaccinated. Also, individuals are less willing to get vaccinated if their political preferences are related to the right-wing. The results led to three main health and social implications: i) the vaccination strategy campaigns should take in count vaccine efficacy and political aspects; ii) the vaccination process should be adapted to regions with different political positions; and iii) a reinforcement in the educational policies of the vaccine's importance to the public health, to avoid the politization of a health issue.

  • Journal article
    Wangdi K, Unwin HJT, Penjor K, Tsheten T, Tobgyal, Clements A, Gray D, Kotepui M, Bhatt S, Gething Pet al., 2024,

    Estimating the impact of imported malaria on local transmission in a near elimination setting: a case study from Bhutan.

    , Lancet Reg Health Southeast Asia, Vol: 31

    BACKGROUND: Bhutan has achieved a substantial reduction in both malaria morbidity and mortality over the last two decades and is aiming for malaria elimination certification in 2025. However, a significant percentage of malaria cases in Bhutan are imported (acquired in another country). The aim of the study was to understand how importation drives local malaria transmission in Bhutan. METHODS: Information on geo-located individual-level laboratory-confirmed malaria cases between 2016 and 2020 was obtained from the Bhutan Vector-borne Disease Control Program. Records included the date of diagnosis and treatment, type of cases classified as indigenous or imported, and malaria species. Hawkes Processes were used to study the role of imported malaria in local transmission in Bhutan. We imposed 15 days delay for a mosquito to become infectious in the model. FINDINGS: There were 285 cases during the study period and 58.6% (159) were imported malaria. 71.1% (113) of these imported cases were Plasmodium vivax and 73.6% (117) were from India. The model suggested that a person remains infectious for 8 days for Plasmodium falciparum malaria but over 19 days for P. vivax. The background intensity from imported malaria cases was much greater for P. vivax cases (maximum 0.17) resulting in more importations than P. falciparum cases (maximum 0.06). However, model fitting suggested that local P. falciparum transmission was mainly driven by importations but additional factors such as relapse played a role for P. vivax. INTERPRETATION: Imported malaria cases are key drivers of transmission within Bhutan, with most cases since 2016 being P. vivax. Control programmes should be devised to target interventions towards the P. vivax strain and test those who are more likely to bring in imported malaria cases or acquire it from returning travellers. FUNDING: None.

  • Journal article
    Atsame J, Stapley JN, Ramani A, Mourou R, Ntsame E, Efame E, Angue O-N, Obiang J-L, Pilotte N, Gass K, Basáñez M-Get al., 2024,

    Comparison of diagnostic tools to assess the feasibility of programmatic use of rapid diagnostic tests for onchocerciasis: a dataset from Gabon

    , Data in Brief, Vol: 57, ISSN: 2352-3409

    Due to the success of large-scale ivermectin mass drug administration (MDA), the aim of onchocerciasis intervention efforts have shifted from control of the disease to elimination of transmission. This has necessitated a greater understanding and comparison of the performance of diagnostic tools in hypoendemic (low prevalence) settings which had not been incorporated into large-scale MDA programmes before the goal switched from onchocerciasis elimination as a public health problem to elimination (interruption) of transmission (EOT). Data on age, sex and duration of residence were collected, prior to ivermectin treatment, across Gabon in 2015 from 5,829 participants in 67 communities from 14 districts. Skin-snip samples (for detection of Onchocerca volvulus microfilariae) were obtained from 4,350 (75 %) and blood samples (for detection of presence of IgG4 antibodies against the O. volvulus Ov16 antigen) from 4,257 of those skin-snip tested (98 %).Whole blood was tested in the field using the SD Ov16 Rapid Diagnostic Test Prototype (Ov16 RDT). Dried blood spots (DBS) were prepared for all blood-sampled individuals. After assessing DBS quality, 2,990 (70 %) samples underwent valid analysis in the lab using horseradish peroxidase (HRP) Ov16 enzyme-linked immunosorbent assay (Ov16 ELISA). The number of positive individuals varied between diagnostic tools with skin-snip microscopy, Ov16 RDT and Ov16 ELISA detecting 337/4,350 (8 %, 95 % CI =7 %–9 %), 383/4,257 (9 %, 8 %–10 %) and 348/2,990 (12 %, 10 %–13 %), respectively. Data were analysed to understand the age profiles of microfilarial and IgG4 antibody prevalence by diagnostic and mapped across Gabon.These data have reuse potential for policy makers, test manufacturers and country programmes when making determinations at community level of the suitability of using Ov16 RDT for conducting delineation mapping or evaluating the current stage of a community or, more generally, an evaluation unit along the

  • Journal article
    Kwok KO, Huynh T, Wei WI, Wong SYS, Riley S, Tang Aet al., 2024,

    Utilizing large language models in infectious disease transmission modelling for public health preparedness.

    , Comput Struct Biotechnol J, Vol: 23, Pages: 3254-3257, ISSN: 2001-0370

    INTRODUCTION: OpenAI's ChatGPT, a Large Language Model (LLM), is a powerful tool across domains, designed for text and code generation, fostering collaboration, especially in public health. Investigating the role of this advanced LLM chatbot in assisting public health practitioners in shaping disease transmission models to inform infection control strategies, marks a new era in infectious disease epidemiology research. This study used a case study to illustrate how ChatGPT collaborates with a public health practitioner in co-designing a mathematical transmission model. METHODS: Using natural conversation, the practitioner initiated a dialogue involving an iterative process of code generation, refinement, and debugging with ChatGPT to develop a model to fit 10 days of prevalence data to estimate two key epidemiological parameters: i) basic reproductive number (Ro) and ii) final epidemic size. Verification and validation processes are conducted to ensure the accuracy and functionality of the final model. RESULTS: ChatGPT developed a validated transmission model which replicated the epidemic curve and gave estimates of Ro of 4.19 (95 % CI: 4.13- 4.26) and a final epidemic size of 98.3 % of the population within 60 days. It highlighted the advantages of using maximum likelihood estimation with Poisson distribution over least squares method. CONCLUSION: Integration of LLM in medical research accelerates model development, reducing technical barriers for health practitioners, democratizing access to advanced modeling and potentially enhancing pandemic preparedness globally, particularly in resource-constrained populations.

  • Journal article
    van Elsland S, O'Hare R, McCabe R, Laydon D, Ferguson N, Cori A, Christen Pet al., 2024,

    Policy impact of the Imperial College COVID-19 Response Team: global perspective and UK case study

    , Health Research Policy and Systems, Vol: 22, ISSN: 1478-4505

    BackgroundMathematical models and advanced analytics play an important role in policy decision making and mobilizing action. The Imperial College Coronavirus Disease 2019 (COVID-19) Response Team (ICCRT) provided continuous, timely and robust epidemiological analyses to inform the policy responses of governments and public health agencies around the world. This study aims to quantify the policy impact of ICCRT outputs, and understand which evidence was considered policy-relevant during the COVID-19 pandemic.MethodsWe collated all outputs published by the ICCRT between 01-01-2020 and 24-02-2022 and conducted inductive thematic analysis. A systematic search of the Overton database identified policy document references, as an indicator of policy impact.ResultsWe identified 620 outputs including preprints (16%), reports (29%), journal articles (37%) and news items (18%). More than half (56%) of all reports and preprints were subsequently peer-reviewed and published as a journal article after 202 days on average. Reports and preprints were crucial during the COVID-19 pandemic to the timely distribution of important research findings. One-fifth of ICCRT outputs (21%) were available to or considered by United Kingdom government meetings. Policy documents from 41 countries in 26 different languages referenced 43% of ICCRT outputs, with a mean time between publication and reference in the policy document of 256 days. We analysed a total of 1746 policy document references. Two-thirds (61%) of journal articles, 39% of preprints, 31% of reports and 16% of news items were referenced in one or more policy documents (these 217 outputs had a mean of 8 policy document references per output). The most frequent themes of the evidence produced by the ICCRT reflected the evidence-need for policy decision making, and evolved accordingly from the pre-vaccination phase [severity, healthcare demand and capacity, and non-pharmaceutical interventions (NPIs)] to the vaccination phase of the ep

  • Journal article
    Grant R, de Kraker MEA, Buetti N, Jackson H, Abbas M, Sobel JA, Sommerstein R, Eder M, Balmelli C, Troillet N, Schreiber PW, Jent P, Senn L, Flury D, Tschudin-Sutter S, Buettcher M, Süveges M, Urbini L, Keiser O, Roder U, Harbarth S, Zanella M-C, CH-SUR study groupet al., 2024,

    In-hospital outcomes of healthcare-associated COVID-19 (Omicron) versus healthcare-associated influenza: a retrospective, nationwide cohort study in Switzerland.

    , Clin Infect Dis

    BACKGROUND: As COVID-19 is integrated into existing infectious disease control programs, it is important to understand the comparative clinical impact of COVID-19 and other respiratory diseases. METHODS: We conducted a retrospective cohort study of patients with symptomatic healthcare-associated COVID-19 or influenza reported to the nationwide, hospital-based surveillance system in Switzerland. Included patients were adults (≥18 years) hospitalized for ≥3 days in tertiary care and large regional hospitals. Patients had COVID-19 symptoms and a RT-PCR-confirmed SARS-CoV-2 infection ≥3 days after hospital admission between 1 February 2022 and 30 April 2023, or influenza symptoms and a RT-PCR-confirmed influenza A or B infection ≥3 days after hospital admission between 1 November 2018 and 30 April 2023. Primary and secondary outcomes were 30-day in-hospital mortality and admission to intensive care unit (ICU), respectively. Cox regression (Fine-Gray model) was used to account for time-dependency and competing events, with inverse probability weighting to adjust for confounding. RESULTS: We included 2901 patients with symptomatic healthcare-associated COVID-19 (Omicron) and 868 patients with symptomatic healthcare-associated influenza from nine hospitals. We found a similar case fatality ratio between healthcare-associated COVID-19 (Omicron) (6.2%) and healthcare-associated influenza (6.1%) patients; after adjustment, patients had a comparable subdistribution hazard ratio for 30-day in-hospital mortality (0.91, 95%CI 0.67-1.24). A similar proportion of patients were admitted to ICU (2.4% COVID-19; 2.6% influenza). CONCLUSIONS: COVID-19 and influenza continue to cause severe disease among hospitalized patients. Our results suggest that in-hospital mortality risk of healthcare-associated COVID-19 (Omicron) and healthcare-associated influenza are comparable.

  • Journal article
    Oliveira LMA, Costa NS, Mestrovic T, Jauneikaite E, Pinto TCAet al., 2024,

    The battle against antimicrobial resistance is more important now than ever: time to educate, advocate and act

    , International Journal of Infectious Diseases, ISSN: 1201-9712
  • Journal article
    Shah A, 2024,

    The effects of COVID-19 on antifungal prescribing in the UK – lessons to learn

    , Journal of Fungi, ISSN: 2309-608X

    Fungal infections are increasingly prevalent however antifungal stewardship attracts little funding or attention. Previous studies have shown that knowledge of guidelines and scientific evidence regarding antifungals is poor, leading to prescribing based on personal experiences and the inherent biases this entails. We carried out a retrospective study of inpatient antifungal usage at two major hospitals. We assessed the longitudinal trends in antifungal usage and the effect of COVID-19 on antifungal prescription, alongside levels of empirical and diagnostically-targeted antifungal usage. Our results showed that the longitudinal patterns of total systemic antifungal usage within the trusts were similar to national prescribing trends, however the composition of antifungals varied considerably, even when looking exclusively at the more homogenous group of COVID-19 patients. We show a high level of empirical antifungal use in COVID-19 patients, with neither trust adhering to international recommendations and following prior prescribing habit. This study highlights the significant challenges to optimise antifungal use with prescribing behaviour largely dictated by habit, a lack of adherence to guidelines and high rates of empirical non-diagnostic based prescribing. Further research and resource are required to understand the impact of antifungal stewardship on improving antifungal prescribing behaviours in this setting and the effects on outcome.

  • Journal article
    de Villiers MJ, de Villiers E, Nayagam S, Hallett TBet al., 2024,

    Direct and indirect effects of hepatitis B vaccination in four low- and middle-income countries.

    , Epidemics, Vol: 49

    Population-level vaccination effects of the hepatitis B vaccine were investigated in four low- and middle-income countries with different levels of vertical and horizontal transmission. Indirect vaccination effects constitute a large proportion of overall vaccination effects of the vaccination programmes in all four countries (over 70% by 2030 in all four countries). However, countries with higher levels of vertical transmission benefit less from indirect vaccination effects from the infant hepatitis B vaccine series during the first decades of the vaccination programme, making the birth dose vaccine more important in these countries. Vaccination, even at levels that do not fully control transmission, has a great effect on the development of disease as it also increases the average age of infection, thereby causing a decrease in the number of chronic infections relative to the number of acute infections.

This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.

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