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Although system dynamics [SD] and agent-based modelling [ABM] have individually served as effective tools to understand the Covid-19 dynamics, combining these methods in a hybrid simulation model can help address Covid-19 questions and study systems and settings that are difficult to study with a single approach. To examine the spread and outbreak of Covid-19 across multiple care homes via bank/agency staff and evaluate the effectiveness of interventions targeting this group, we develop an integrated hybrid simulation model combining the advantages of SD and ABM. We also demonstrate how we use several approaches adapted from both SD and ABM practices to build confidence in this model in response to the lack of systematic approaches to validate hybrid models. Our modelling results show that the risk of infection for residents in care homes using bank/agency staff was significantly higher than those not using bank/agency staff (Relative risk [RR] 2.65, 95% CI 2.57-2.72). Bank/agency staff working across several care homes had a higher risk of infection compared with permanent staff working in a single care home (RR 1.55, 95%CI 1.52-1.58). The RR of infection for residents is negatively correlated to bank/agency staff's adherence to weekly PCR testing. Within a network of heterogeneous care homes, using bank/agency staff had the most impact on care homes with lower intra-facility transmission risks, higher staff-to-resident ratio, and smaller size. Forming bubbles of care homes had no or limited impact on the spread of Covid-19. This modelling study has implications for policy makers considering developing effective interventions targeting staff working across care homes during the ongoing and future pandemics.
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COVID-19/transmisión , Simulación por Computador , Personal de Salud , Casas de Salud/organización & administración , Análisis de Sistemas , COVID-19/virología , Humanos , SARS-CoV-2/aislamiento & purificaciónRESUMEN
The recent report of the Intergovernmental Panel on Climate Change is stark in its warnings about the changing climate, including future increases in the frequency and intensity of extremely hot weather. The well-established impacts of extreme heat on human health have led to widespread implementation of national and city-wide heat plans for mitigating such impacts. Evaluations of the effectiveness of some heat plans have been published, with previous reviews highlighting key methodological challenges. This article reviews methods used since and that address those challenges, so helping to set an agenda for improving evaluations of heat plans in terms of their effectiveness in reducing heat-health impacts. We examined the reviews that identified the methodological challenges and systematically searched the literature to find evaluations that had since been conducted. We found 11 evaluations. Their methods help address the key challenge of identifying study control groups and address other challenges to a limited extent. For future evaluations, we recommend: utilising recent evaluation methodologies, such as difference-in-differences quasi-experimental designs where appropriate; cross-agency working to utilise data on morbidity and confounders; adoption of a proposed universal heat index; and greater publication of evaluations. More evaluations should assess morbidity outcomes and be conducted in low- and middle-income countries. Evaluations of heat plans globally should employ robust methodologies, as demonstrated in existing studies and potentially transferrable from other fields. Publication of such evaluations will advance the field and thus help address some of the health challenges resulting from our changing climate.
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Calor Extremo , Cambio Climático , Predicción , Calor , Humanos , MorbilidadRESUMEN
Healthcare-associated infections (HAIs) are a major public health problem as they pose a serious risk for patients and providers, increasing morbidity, mortality, and length of stay, as well as costs to patients and the health system. Prevention and control of HAIs has, therefore, become a priority for most healthcare systems. Systems simulation models have provided insights into the dynamics of HAIs and help to evaluate the effect of infection control interventions. However, as each systems simulation modeling method has strengths and limitations, combining these methods in hybrid models can offer a better tool to gain complementary views on, and deeper insights into HAIs. Hybrid models can, therefore, assist decision-making at different levels of management, and provide a balance between simulation performance and result accuracy. This report discusses these benefits in more depth but also highlights some challenges associated with the use of hybrid simulation models for modeling HAIs.
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Infección Hospitalaria , Atención a la Salud , Humanos , Control de InfeccionesRESUMEN
Antimicrobial resistance is a serious challenge to the success and sustainability of our healthcare systems. There has been increasing policy attention given to antimicrobial resistance in the last few years, and increased amounts of funding have been channeled into funding for research and development of antimicrobial agents. Nevertheless, manufacturers doubt whether there will be a market for new antimicrobial technologies sufficient to enable them to recoup their investment. Health technology assessment (HTA) has a critical role in creating confidence that if valuable technologies can be developed they will be reimbursed at a level that captures their true value. We identify 3 deficiencies of current HTA processes for appraising antimicrobial agents: a methods-centric approach rather than problem-centric approach for dealing with new challenges, a lack of tools for thinking about changing patterns of infection, and the absence of an approach to epidemiological risks. We argue that, to play their role more effectively, HTA agencies need to broaden their methodological tool kit, design and communicate their analysis to a wider set of users, and incorporate long-term policy goals, such as containing resistance, as part of their evaluation criteria alongside immediate health gains.
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Farmacorresistencia Bacteriana , Evaluación de la Tecnología Biomédica , Antibacterianos/uso terapéutico , Humanos , Cuidados PaliativosRESUMEN
Over 95% of post-mortem samples from the 1918 pandemic, which caused 50 to 100 million deaths, showed bacterial infection complications. The introduction of antibiotics in the 1940s has since reduced the risk of bacterial infections, but growing resistance to antibiotics could increase the toll from future influenza pandemics if secondary bacterial infections are as serious as in 1918, or even if they are less severe. We develop a valuation model of the option to withhold wide use of an antibiotic until significant outbreaks such as pandemic influenza or foodborne diseases are identified. Using real options theory, we derive conditions under which withholding wide use is beneficial, and calculate the option value for influenza pandemic scenarios that lead to secondary infections with a resistant Staphylococcus aureus strain. We find that the value of withholding an effective novel oral antibiotic can be positive and significant unless the pandemic is mild and causes few secondary infections with the resistant strain or if most patients can be treated intravenously. Although the option value is sensitive to parameter uncertainty, our results suggest that further analysis on a case-by-case basis could guide investment in novel agents as well as strategies on how to use them.
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Antibacterianos/provisión & distribución , Antibacterianos/uso terapéutico , Infecciones Bacterianas/tratamiento farmacológico , Infecciones Bacterianas/epidemiología , Gripe Humana/epidemiología , Pandemias/prevención & control , Antibacterianos/administración & dosificación , Antibacterianos/efectos adversos , Investigación Biomédica/organización & administración , Planificación en Desastres/organización & administración , Farmacorresistencia Bacteriana Múltiple , Humanos , Modelos Teóricos , Reserva Estratégica/organización & administración , Organización Mundial de la SaludRESUMEN
OBJECTIVE: An estimated 6-10 million people in India live with active epilepsy, and less than half are treated. We analyze the health and economic benefits of three scenarios of publicly financed national epilepsy programs that provide: (1) first-line antiepilepsy drugs (AEDs), (2) first- and second-line AEDs, and (3) first- and second-line AEDs and surgery. METHODS: We model the prevalence and distribution of epilepsy in India using IndiaSim, an agent-based, simulation model of the Indian population. Agents in the model are disease-free or in one of three disease states: untreated with seizures, treated with seizures, and treated without seizures. Outcome measures include the proportion of the population that has epilepsy and is untreated, disability-adjusted life years (DALYs) averted, and cost per DALY averted. Economic benefit measures estimated include out-of-pocket (OOP) expenditure averted and money-metric value of insurance. RESULTS: All three scenarios represent a cost-effective use of resources and would avert 800,000-1 million DALYs per year in India relative to the current scenario. However, especially in poor regions and populations, scenario 1 (which publicly finances only first-line therapy) does not decrease the OOP expenditure or provide financial risk protection if we include care-seeking costs. The OOP expenditure averted increases from scenarios 1 through 3, and the money-metric value of insurance follows a similar trend between scenarios and typically decreases with wealth. In the first 10 years of scenarios 2 and 3, households avert on average over US$80 million per year in medical expenditure. SIGNIFICANCE: Expanding and publicly financing epilepsy treatment in India averts substantial disease burden. A universal public finance policy that covers only first-line AEDs may not provide significant financial risk protection. Covering costs for both first- and second-line therapy and other medical costs alleviates the financial burden from epilepsy and is cost-effective across wealth quintiles and in all Indian states.
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Costo de Enfermedad , Análisis Costo-Beneficio/economía , Epilepsia/economía , Financiación Gubernamental/economía , Beneficios del Seguro/economía , Análisis de Sistemas , Análisis Costo-Beneficio/métodos , Epilepsia/epidemiología , Epilepsia/terapia , Financiación Gubernamental/métodos , Humanos , India/epidemiología , Beneficios del Seguro/métodos , Resultado del TratamientoAsunto(s)
COVID-19/terapia , Atención a la Salud , Manejo de la Enfermedad , Planificación en Salud , Neumonía Viral/terapia , COVID-19/epidemiología , COVID-19/prevención & control , Prueba de COVID-19 , Comorbilidad , Humanos , Trastornos Mentales/terapia , Pandemias , Neumonía Viral/epidemiología , Neumonía Viral/prevención & control , Neumonía Viral/virología , SARS-CoV-2 , TelemedicinaRESUMEN
The movement of populations between locations and activities can result in complex transmission dynamics, posing significant challenges in controlling infectious diseases like COVID-19. Notably, networks of care homes create an ecosystem where staff and visitor movement acts as a vector for disease transmission, contributing to the heightened risk for their vulnerable communities. Care homes in the UK were disproportionately affected by the first wave of the COVID-19 pandemic, accounting for almost half of COVID-19 deaths during the period of 6th March - 15th June 2020 and so there is a pressing need to explore modelling approaches suitable for such systems. We develop a generic compartmental Susceptible - Exposed - Infectious - Recovered - Dead (SEIRD) metapopulation model, with care home residents, care home workers, and the general population modelled as subpopulations, interacting on a network describing their mixing habits. We illustrate the model application by analysing the spread of COVID-19 over the first wave of the COVID-19 pandemic in the NHS Lothian health board, Scotland. We explicitly model the outbreak's reproduction rate and care home visitation level over time for each subpopulation and execute a data fit and sensitivity analysis, focusing on parameters responsible for inter-subpopulation mixing: staff-sharing, staff shift patterns and visitation. The results from our sensitivity analysis show that restricting staff sharing between homes and staff interaction with the general public would significantly mitigate the disease burden. Our findings indicate that protecting care home staff from disease, coupled with reductions in staff-sharing across care homes and expedient cancellations of visitations, can significantly reduce the size of outbreaks in care home settings.
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OBJECTIVES: Allocation of development aid for health is controversial and challenging. In recent years, several planning-software tools have promised to help decision-makers align resource allocation with their objectives, more clearly connect prioritisation to evidence and local circumstances, and increase transparency and comparability. We aim to explore these tools to provide insight into their fitness for purpose and suggest future directions to fulfil that promise. DESIGN: We identified seven tools that met the inclusion criteria and developed an evaluation framework to compare them along two dimensions for assessing fitness for purpose: ability to produce analyses adhering to principles laid out in the International Decisions Support Initiative (iDSI) Reference Case for health economic evaluations; and resources required, including expertise and time. We extracted information from documentation and tool use and sent this information to tool developers for confirmation. RESULTS: We categorise the tools into evidence-generating ones, evidence-syntheses ones and process support ones. Tools' fitness for purpose varies by the context, technical capacity and time limitation. The tools adhere to several reference case principles but often not to all of them. The source and underlying assumptions of prepopulated data are often opaque. Comparing vertical interventions across diseases and health system strengthening ones remains challenging. CONCLUSIONS: The plethora of tools that aid priority setting in different ways is encouraging. Developers and users should place further emphasis on their ability to produce analyses that adhere to prioritisation principles. Opportunities for further development include using evidence-generating tools and multicriteria decision analysis approaches complimentarily. However, maintaining tool simplicity should also be considered to allow wider access.
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Países en Desarrollo , Pobreza , Humanos , Análisis Costo-Beneficio , Documentación , Ejercicio FísicoRESUMEN
OBJECTIVE: The barriers to delivering clinical non-communicable disease services in low- and middle-income countries have risen with the onset of COVID-19. Using Ghana as a case study, this article examines the changes COVID-19 has brought to diabetes service delivery and considers policy responses to deal with future such outbreaks. METHODS: We conducted 18 interviews between November 2020 and February 2021 with health professionals and administrators from primary, secondary and tertiary facilities within the Ghana Health Service. The analysis was performed using deductive and inductive methods. RESULTS: There were six general themes in interviewees' responses: (1) COVID-19 had exacerbated the problems of high medicine and service costs and medicine shortages, (2) the pandemic had exacerbated problems of poor patient record keeping, (3) COVID-19 had reduced the availability of suitably trained health providers, (4) staff had become demoralized by management's unwillingness to make innovative changes to cope with the pandemic, (5) COVID-19 led to a reorganization of diabetes services, and (6) the country's national health insurance scheme lacked flexibility in dealing with the pandemic. CONCLUSIONS: Access to resources is limited in LMICs. However, our study highlights practical policy responses that can improve health providers' response to COVID-19 and future pandemics.
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COVID-19 , Diabetes Mellitus , Humanos , Pandemias , Ghana/epidemiología , COVID-19/epidemiología , Atención a la Salud , Diabetes Mellitus/epidemiología , Diabetes Mellitus/terapiaRESUMEN
Novel subscription payment schemes are one of the approaches being explored to tackle the threat of antimicrobial resistance. Under these schemes, some or all of the payment is made via a fixed "subscription" payment, which provides a funder unlimited access to the treatment for a specific duration, rather than relying purely on a price per pill. Subscription-based schemes guarantee pharmaceutical firms income that incentivises investment in developing new antibiotics, and can promote responsible stewardship. From the pharmaceutical perspective, revenue is disassociated from sales, removing benefits from push marketing strategies. We investigate this from the funder perspective, and consider that the funder plays a key role in promoting responsible antibiotic stewardship by choosing the price per pill for providers such that this encourages appropriate antibiotic use. This choice determines the payment structure, and we investigate the impact of this choice through the lens of social welfare. We present a mathematical model of subscription payment schemes, explicitly featuring fixed and volume-based payment components for a given treatment price. Total welfare returned at a societal level is then estimated (incorporating financial costs and monetised benefits). We consider a practical application of the model to development of novel antibiotic treatment for Gonorrhoea, and examine the optimal treatment price under different parameterisations. Specifically, we analyse two contrasting scenarios - one where a new antibiotic's prioritised role is reducing transmission, and one where a more pressing requirement is conserving the antibiotic as an effective last defence. Critically, this analysis demonstrates that effective roll-out of a subscription payment scheme for a new antibiotic requires a comprehensive assessment of the benefits gained from treatment. We discuss the insights this work presents on the nature of these payment schemes, and how these insights can enable decision-makers to take the first steps in determining effective structuring of subscription payment schemes.
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Antibacterianos , Antibacterianos/uso terapéutico , Costos y Análisis de Costo , Humanos , Preparaciones FarmacéuticasRESUMEN
OBJECTIVE: Health system strengthening (HSS) activities should accompany disease-targeting interventions in low/middle-income countries (LMICs). Economic evaluations provide information on how these types of investment might best be balanced but can be challenging. We conducted a systematic review to evaluate how researchers address these economic evaluation challenges. METHODS: We identified studies about economic evaluation of HSS activities in LMICs using a two-stage approach. First, we conducted a broad search to identify areas where economic evaluations of HSS activities were being conducted. Next, we selected specific interventions for more targeted literature review. We extracted study characteristics using the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) checklist. Finally, we summarised authors' modelling decisions using a framework that examines how models are developed to emphasise generalisability, precision, or realism. FINDINGS: Our searches produced 1978 studies, out of which we included 36. Most studies used data from prospective trials and calculated cost-effectiveness directly from these trial inputs, rather than using simulation methods. As a group, these studies primarily emphasised precision and realism over generalisability, meaning that their results were best suited to specific settings. CONCLUSIONS: The number of included studies was small. Our findings suggest that most economic evaluations of HSS do not leverage methods like sensitivity analyses or inputs from literature review that would produce more generalisable (but potentially less precise) results. More research into how decision-makers would use economic evaluations to define the expansion path to strengthening health systems would allow for conceptualising impactful work on the economic value of HSS.
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Renta , Pobreza , Análisis Costo-Beneficio , Programas de Gobierno , Humanos , Estudios ProspectivosRESUMEN
The development of COVID-19 vaccines does not imply the end of the global pandemic as now countries have to purchase enough COVID-19 vaccine doses and work towards their successful rollout. Vaccination across the world has progressed slowly in all, but a few high-income countries (HICs) as governments learn how to vaccinate their entire populations amidst a pandemic. Most low- and middle-income countries (LMICs) have been relying on the COVID-19 Vaccines Global Access (COVAX) Facility to obtain vaccines. COVAX aims to provide these countries with enough doses to vaccinate 20% of their populations. LMICs will likely encounter additional barriers and challenges rolling out vaccines compared HICs despite their significant experience from the Expanded Programme on Immunisation (EPI). This study explores potential barriers that will arise during the COVID-19 vaccine rollout in lower-middle-income countries and how to overcome them. We conducted sixteen semi-structured interviews with national-level stakeholders from Ghana and Bangladesh (eight in each country). Stakeholders included policymakers and immunisation programme experts. Data were analysed using a Framework Analysis technique. Stakeholders believed their country could use existing EPI structures for the COVID-19 vaccine rollout despite existing challenges with the EPI and despite its focus on childhood immunisation rather than vaccinating the entire population over a short period of time. Stakeholders suggested increasing confidence in the vaccine through community influencers and by utilising local government accredited institutions such as the Drug Authorities for vaccine approval. Additional strategies they discussed included training more health providers and recruiting volunteers to increase vaccination speed, expanding government budgets for COVID-19 vaccine purchase and delivery, and exploring other financing opportunities to address in-country vaccine shortages. Stakeholders also believed that LMICs may encounter challenges complying with priority lists. Our findings suggest that COVID-19 vaccination is different from previous vaccination programs, and therefore, policymakers have to expand the EPI structure and also take a systematic and collaborative approach to plan and effectively rollout the vaccines.
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Vacunas contra la COVID-19 , COVID-19 , Programas de Inmunización/organización & administración , COVID-19/prevención & control , Vacunas contra la COVID-19/administración & dosificación , Países en Desarrollo , Humanos , VacunaciónRESUMEN
BACKGROUND: This study examines the impact of visitation and cohorting policies as well as the care home population size upon the spread of COVID-19 and the risk of outbreak occurrence in this setting. METHODS: Agent-based modelling RESULTS: The likelihood of the presence of an outbreak in a care home is associated with the care home population size. Cohorting of residents and staff into smaller, self-contained units reduces the spread of COVID-19. Restricting the number of visitors to the care home to shield its residents does not significantly impact the cumulative number of infected residents and risk of outbreak occurrence in most scenarios. Only when the community prevalence where staff live is considerably lower than the prevalence where visitors live (the former prevalence is less than or equal to 30% of the latter), relaxing visitation increases predicted infections much more significantly than it does in other scenarios. Maintaining a low infection probability per resident-visitor contact helps reduce the effect of allowing more visitors into care homes. CONCLUSIONS: Our model predictions suggest that cohorting is effective in controlling the spread of COVID-19 in care homes. However, according to predictions shielding residents in care homes is not as effective as predicted in a number of studies that have modelled shielding of vulnerable population in the wider communities.
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COVID-19 , Casas de Salud , Visitas a Pacientes , COVID-19/prevención & control , Brotes de Enfermedades/prevención & control , Humanos , PolíticasRESUMEN
Ghana has signed on to the United Nations Sustainable Development Goal to achieve universal health coverage (UHC), ensuring that all individuals receive the health care they require without financial hardship. Achieving that goal is a difficult task in any setting. The challenges are further exacerbated by a changing disease landscape, as the burden of non-communicable diseases (NCDs) is increasing and creating a dual burden along with infectious diseases. This study explores the existing health system for delivering hypertension care and the challenges of delivering UHC for hypertension in Ghana. Document analysis of national health reports, policies and legislations along with a review of research articles was conducted to explore the challenges of delivering UHC for NCDs in Ghana, and hypertension in particular. The main themes and indicators related to the challenges of delivering UHC for hypertension were mapped and analysed. The main challenges to delivering UHC for hypertension can be grouped into population and patient, on the one hand, and health system factors, on the other. Population and patient factors include (1) unhealthy lifestyles overburdening the health system, (2) poor health-seeking behaviour and (3) poor adherence to medication, which has led to uncontrolled cases and poor clinical outcomes even among treated patients with hypertension. Health system factors include (1) inadequate health system capacity for early diagnosis due to an increasing number of patients, (2) inequitable distribution of health care facilities affecting access, (3) financial sustainability of the National Health Insurance Scheme and delays in reimbursement of claims to facilities that affect the health system's ability to provide timely management of hypertension and (4) health care facilities and practitioners' use of non-standardized and uncalibrated blood pressure measuring equipment. Ghana therefore will need to make important decisions to overcome operational and financial challenges on its path to UHC.
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Hipertensión , Cobertura Universal del Seguro de Salud , Atención a la Salud , Ghana , Humanos , Hipertensión/tratamiento farmacológico , Programas Nacionales de SaludRESUMEN
BACKGROUND: Care homes are vulnerable to widespread transmission of severe acute respiratory coronavirus virus 2 (SARS-CoV-2) with poor outcomes for staff and residents. Infection control interventions in care homes need to not only be effective in containing the spread of coronavirus disease 2019 (COVID-19) but also feasible to implement in this special setting which is both a healthcare institution and a home. METHODS: We developed an agent-based model that simulates the transmission dynamics of COVID-19 via contacts between individuals, including residents, staff members, and visitors in a care home setting. We explored a representative care home in Scotland in our base case and explore other care home setups in an uncertainty analysis. We evaluated the effectiveness of a range of intervention strategies in controlling the spread of COVID-19. RESULTS: In the presence of the reference interventions that have been implemented in many care homes, including testing of new admissions, isolation of symptomatic residents, and restricted public visiting, routine testing of staff appears to be the most effective and practical approach. Routine testing of residents is no more effective as a reference strategy while routine testing of both staff and residents only shows a negligible additive effect. Modeling results are very sensitive to transmission probability per contact, but the qualitative finding is robust to varying parameter values in our uncertainty analysis. CONCLUSIONS: Our model predictions suggest that routine testing should target staff in care homes in conjunction with adherence to strict hand hygiene and using personal protective equipment to reduce risk of transmission per contact.
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COVID-19 , Higiene de las Manos , Humanos , Control de Infecciones , Equipo de Protección Personal , SARS-CoV-2RESUMEN
Residents living in long-term care facilities (LTCFs) are at high risk of contracting healthcare-associated infections (HAIs). The unique operational and cultural characteristics of LTCFs and the currently evolving models of healthcare delivery in Scotland create great challenges for infection prevention and control (IPC). Existing literature that discusses the challenges of infection control in LTCFs focuses on operational factors within a facility and does not explore the challenges associated with higher levels of management and the lack of evidence to support IPC practices in this setting.1-7 Here, we provide a broader view of challenges faced by LTCFs in the context of the current health and social care models in Scotland. Many of these challenges are also faced in the rest of the United Kingdom and internationally.
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Infección Hospitalaria , Cuidados a Largo Plazo , Infección Hospitalaria/prevención & control , Instituciones de Salud , Humanos , Control de Infecciones , EscociaRESUMEN
BACKGROUND: Health care-associated infections (HAIs) are a global health burden because of their significant impact on patient health and health care systems. Mechanistic simulation modeling that captures the dynamics between patients, pathogens, and the environment is increasingly being used to improve understanding of epidemiological patterns of HAIs and to facilitate decisions on infection prevention and control (IPC). The purpose of this review is to present a systematic review to establish (1) how simulation models have been used to investigate HAIs and their mitigation and (2) how these models have evolved over time, as well as identify (3) gaps in their adoption and (4) useful directions for their future development. METHODS: The review involved a systematic search and identification of studies using system dynamics, discrete event simulation, and agent-based model to study HAIs. RESULTS: The complexity of simulation models developed for HAIs significantly increased but heavily concentrated on transmission dynamics of methicillin-resistant Staphylococcus aureus in the hospitals of high-income countries. Neither HAIs in other health care settings, the influence of contact networks within a health care facility, nor patient sharing and referring networks across health care settings were sufficiently understood. CONCLUSIONS: This systematic review provides a broader overview of existing simulation models in HAIs to identify the gaps and to direct and facilitate further development of appropriate models in this emerging field.
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Infección Hospitalaria , Staphylococcus aureus Resistente a Meticilina , Infección Hospitalaria/epidemiología , Infección Hospitalaria/prevención & control , Atención a la Salud , Hospitales , Humanos , Control de InfeccionesRESUMEN
The increase of multidrug resistance and resistance to last-line antibiotics is a major global public health threat. Although surveillance programs provide useful current and historical information on the scale of the problem, the future emergence and spread of antibiotic resistance is uncertain, and quantifying this uncertainty is crucial for guiding decisions about investment in antibiotics and resistance control strategies. Mathematical and statistical models capable of projecting future rates are challenged by the paucity of data and the complexity of the emergence and spread of resistance, but experts have relevant knowledge. We use the Classical Model of structured expert judgment to elicit projections with uncertainty bounds of resistance rates through 2026 for nine pathogen-antibiotic pairs in four European countries and empirically validate the assessments against data on a set of calibration questions. The performance-weighted combination of experts in France, Spain, and the United Kingdom projected that resistance for five pairs on the World Health Organization's priority pathogens list (E. coli and K. pneumoniae resistant to third-generation cephalosporins and carbapenems and MRSA) would remain below 50% in 2026. In Italy, although upper bounds of 90% credible ranges exceed 50% resistance for some pairs, the medians suggest Italy will sustain or improve its current rates. We compare these expert projections to statistical forecasts based on historical data from the European Antimicrobial Resistance Surveillance Network (EARS-Net). Results from the statistical models differ from each other and from the judgmental forecasts in many cases. The judgmental forecasts include information from the experts about the impact of current and future shifts in infection control, antibiotic usage, and other factors that cannot be easily captured in statistical forecasts, demonstrating the potential of structured expert judgment as a tool for better understanding the uncertainty about future antibiotic resistance.
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Farmacorresistencia Bacteriana/efectos de los fármacos , Testimonio de Experto/métodos , Predicción/métodos , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Europa (Continente) , Francia , Humanos , Italia , Juicio , Pruebas de Sensibilidad Microbiana , Modelos Estadísticos , España , Incertidumbre , Reino UnidoRESUMEN
Pneumococcal pneumonia causes an estimated 105 000 child deaths in India annually. The planned introduction of the serotype-based pneumococcal conjugate vaccine (PCV) is expected to avert child deaths, but the high cost of PCV relative to current vaccines provided under the Universal Immunization Programme has been a concern. Cost-effectiveness studies from high-income countries are not readily comparable because of differences in the distribution of prevalent serotypes, population and health systems. We extended IndiaSim, our agent-based simulation model representative of the Indian population and health system, to model the dynamics of Streptococcus pneumoniae. This enabled us to evaluate serotype and overall disease dynamics in the context of the local population and health system, an aspect that is missing in prospective evaluations of the vaccine. We estimate that PCV13 introduction would cost approximately US$240 million and avert US$48.7 million in out-of-pocket expenditures and 34 800 (95% CI 29 600 to 40 800) deaths annually assuming coverage levels and distribution similar to DPT (diphtheria, pertussis and tetanus) vaccination (~77%). Introducing the vaccine protects the population, especially the poorest wealth quintile, from potentially catastrophic expenditure. The net-present value of predicted money-metric value of insurance for 20 years of vaccination is US$160 000 (95% CI US$151 000 to US$168 000) per 100 000 under-fives, and almost half of this protection is for the bottom wealth quintile (US$78 000; 95% CI 70 800 to 84 400). Extending vaccination to 90% coverage averts additional lives and provides additional financial risk protection. Our estimates are sensitive to immunity parameters in our model; however, our assumptions are conservative, and if willingness to pay per years of life lost averted is US$228 or greater, then introducing the vaccine is more cost-effective than our baseline (no vaccination) in more than 95% of simulations.