Vacunas最新文献

{"title":"Filling the global vaccine research vacuum: Scientific denialism, pandemic risk, and the urgency of a new international immunization order","authors":"H.M. Silva","doi":"10.1016/j.vacun.2026.500633","DOIUrl":"10.1016/j.vacun.2026.500633","url":null,"abstract":"<div><h3>Objective</h3><div>To discuss how scientific denialism and political interference in the United States have weakened vaccine research and confidence, increasing pandemic risk, and to analyze the need for a new international vaccine order focused on equity.</div></div><div><h3>Methods</h3><div>Short communication based on a narrative synthesis of peer-reviewed literature and institutional reports on vaccine investment, science governance, vaccine hesitancy, and pandemic risk related to climate change, urbanization, and zoonoses.</div></div><div><h3>Results</h3><div>Evidence shows that political interference and misinformation in the U.S. during COVID-19 undermined scientific agencies, strengthened the antivaccine movement, and contributed to declining coverage and measles resurgence. At the same time, climate change, deforestation, and population density are accelerating pandemic risk, demanding rapid vaccine platforms and global cooperation. The weakening of U.S. leadership creates a strategic vacuum that can be filled by the European Union, China, India, Brazil, and emerging regions.</div></div><div><h3>Conclusions</h3><div>A distributed, cooperative, and equitable international vaccine order is essential to confront growing pandemic risk and counter scientific denialism.</div></div>","PeriodicalId":53407,"journal":{"name":"Vacunas","volume":"27 2","pages":"Article 500633"},"PeriodicalIF":0.0,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling the impact of vaccination on cholera dynamics with water treatment, hygiene, and awareness as control strategies","authors":"M.K. Kolawole,&nbsp;A.A. Adeniji","doi":"10.1016/j.vacun.2025.500487","DOIUrl":"10.1016/j.vacun.2025.500487","url":null,"abstract":"<div><div>Cholera remains a significant public health threat, driven by inadequate sanitation, limited access to clean water, and poor health education. Despite the availability of vaccines, outbreaks persist, underscoring the need to integrate pharmaceutical and non-pharmaceutical interventions. This study investigates cholera transmission dynamics by examining the roles of vaccination, water treatment, hygiene practices, and public awareness.</div><div>An epidemiological model was developed to capture cholera transmission, incorporating both pharmaceutical (vaccination) and non-pharmaceutical (hygiene, water treatment, awareness) control measures. The system of nonlinear differential equations was analyzed using the Homotopy Perturbation Method (HPM), a semi-analytical technique that facilitates both analytical approximation and efficient numerical simulations.</div><div>Analytical and numerical results reveal that vaccination alone significantly reduces transmission rates. However, when combined with non-pharmaceutical measures—particularly public awareness—the reduction is more substantial and sustained. Public awareness plays a catalytic role by promoting behavioral changes and enhancing compliance with hygiene and water safety measures. Numerical simulations show that integrated interventions yield the most pronounced and lasting decline in cholera prevalence.</div><div>The study demonstrates that while vaccination is effective, its impact is maximized when combined with non-pharmaceutical strategies, especially public education. These findings support the adoption of integrated public health approaches and resource allocation strategies in cholera-endemic regions. The results provide a framework for designing targeted and sustainable intervention programs.</div></div>","PeriodicalId":53407,"journal":{"name":"Vacunas","volume":"27 2","pages":"Article 500487"},"PeriodicalIF":0.0,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147740106","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Vacunación frente a herpes zóster en pacientes tratados con fármacos inhibidores de interleucina 5","authors":"Ronald Rodríguez Cogollo ,&nbsp;María Ángela Doronzo ,&nbsp;Juan Gabriel Garcías Ladaria ,&nbsp;Juan Rodríguez-García","doi":"10.1016/j.vacun.2025.500483","DOIUrl":"10.1016/j.vacun.2025.500483","url":null,"abstract":"<div><div>Interleukin-5 (IL-5) inhibitors affect the proliferation, maturation, activation, recruitment, and survival of eosinophils. They are authorised to treat hypereosinophilic syndrome in patients aged ≥12 years, and severe eosinophilic asthma in adults. In Spain, the subunit herpes zoster (HZ) vaccine is authorised for preventing HZ and postherpetic neuralgia in people aged 50 years and over who are undergoing treatment with immunomodulatory or immunosuppressive drugs. However, the latest update to these recommendations excludes people aged 18 years or older who are about to start treatment with mepolizumab or other IL-5 inhibitors due to the increased risk of zoster in people receiving these treatments, as required by the product's summary of product characteristics. Here, we present the case of a patient being treated with mepolizumab who had not been immunised against HZ and subsequently developed an episode of HZ.</div></div>","PeriodicalId":53407,"journal":{"name":"Vacunas","volume":"27 2","pages":"Article 500483"},"PeriodicalIF":0.0,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147740105","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Defining the current models of immunization of immunocompromised patients in Spain, and how to improve them: results of the CARABELA-IP initiative","authors":"Jaime Pérez-Martín ,&nbsp;Manuel García de la Vega ,&nbsp;Gregorio Montes ,&nbsp;Inmaculada Mediavilla ,&nbsp;José Francisco Soto ,&nbsp;Luciano Escudero ,&nbsp;Marta Eva González ,&nbsp;Victoria Nartallo ,&nbsp;María Fernández-Prada ,&nbsp;on behalf of the CARABELA-IP Scientific Committee","doi":"10.1016/j.vacun.2026.500634","DOIUrl":"10.1016/j.vacun.2026.500634","url":null,"abstract":"<div><h3>Objective</h3><div>The CARABELA initiative for the immunocompromised patient (IP) aims to optimize the management of these patients by focusing on four specific objectives: (i) the description of care pathway phases (diagnosis, immunization, and follow-up) and management models for IPs in Spain; (ii) the identification of improvement areas in IP care and potential solutions; (iii) the definition of healthcare quality indicators; and (iv) the dissemination of these findings to enable reference centers to guide others in the management of IP.</div></div><div><h3>Material and methods</h3><div>The CARABELA-IP initiative was developed in three phases: (1) characterization, identifying immunization models, improvement areas, and potential solutions in five pilot centers; (2) validation, through a national multidisciplinary meeting and a Delphi survey to agree on healthcare quality indicators; and (3) dissemination and implementation strategies beyond pilot centers, with a digital Playbook designed to guide the evolution of IP care.</div></div><div><h3>Results</h3><div>Three immunization models were identified based on coordination among departments, highlighting the role of preventive medicine and public health departments and nursing. Nine improvement areas and 24 potential solutions were defined. Furthermore, 28 healthcare quality indicators were validated to monitor the evolution of the immunization models.</div></div><div><h3>Conclusions</h3><div>Coordinated, multidisciplinary strategies are needed to ensure appropriate immunization in the face of diverse and heterogeneous IP management strategies. CARABELA-IP proposes a comprehensive model encompassing the identification, stratification, and protocolized referral of IPs, and promoting the training of healthcare professionals and the education of patients and their household contacts.</div></div>","PeriodicalId":53407,"journal":{"name":"Vacunas","volume":"27 2","pages":"Article 500634"},"PeriodicalIF":0.0,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386812","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Deterministic and stochastic analysis of Hepatitis A virus transmission considering vaccinated population","authors":"S. Jasrotia,&nbsp;R. Kumar","doi":"10.1016/j.vacun.2025.500508","DOIUrl":"10.1016/j.vacun.2025.500508","url":null,"abstract":"&lt;div&gt;&lt;h3&gt;Introduction&lt;/h3&gt;&lt;div&gt;Hepatitis A is a contagious liver disease with necro-inflammatory characteristics resulting from Hepatitis A virus (HAV). HAV remains a significant public health concern due to its high transmissibility, potential to cause outbreaks and substantial burden in regions with inadequate sanitation. The recent resurgence of HAV cases highlights the need to investigate its transmission dynamics and assess the role of vaccination programs in mitigating the progression of HAV disease. In this study, we introduce a mathematical model that incorporates the vaccinated population to analyze the deterministic and stochastic aspects of HAV, providing deeper insights into its epidemiological behavior and control strategies.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Objective&lt;/h3&gt;&lt;div&gt;The objective of this study is to enhance the understanding of HAV disease dynamics while taking into account the characteristics of HAV. A thorough investigation is carried out on several factors influencing HAV transmission. This study also examines the influence of stochastic fluctuations and vaccination strategies on the progression of HAV disease.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Methods&lt;/h3&gt;&lt;div&gt;A deterministic mathematical model was formulated to analyze HAV transmission and the role of vaccination programs on the progression of HAV disease. Stability analysis is conducted at the equilibrium points of the deterministic HAV model. The deterministic HAV model was extended to a stochastic HAV model in order to incorporate the effects of environmental fluctuations on the dynamics of disease transmission. Further, we investigate the criteria under which the HAV disease either becomes extinct or persists within the population. The nonlinear least-squares regression method is implemented to fit the model to HAV data from Kerala. Sensitivity analysis is conducted to determine the role of each parameter in disease dynamics. The Milstein’s higher-order method is utilized to perform numerical simulations with graphical results depicting the behavior of both deterministic and stochastic solutions.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;h3&gt;Results&lt;/h3&gt;&lt;div&gt;The deterministic HAV model exhibited local and global asymptotic stability at both DFE and EE points when &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mi&gt;R&lt;/mi&gt;&lt;mi&gt;d&lt;/mi&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; &lt; 1 and &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mi&gt;R&lt;/mi&gt;&lt;mi&gt;d&lt;/mi&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; &gt; 1, respectively. The stochastic HAV model predicts disease extinction for &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mi&gt;R&lt;/mi&gt;&lt;mi&gt;s&lt;/mi&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; &lt; 1 and persistence within the population for &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mi&gt;R&lt;/mi&gt;&lt;mi&gt;s&lt;/mi&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt; &gt; 1. Sensitivity analysis results indicated that the infected contact rate, vaccination rate and the rate of departure from the infected class had been the most influential parameters on &lt;span&gt;&lt;math&gt;&lt;msub&gt;&lt;mi&gt;R&lt;/mi&gt;&lt;mi&gt;d&lt;/mi&gt;&lt;/msub&gt;&lt;/math&gt;&lt;/span&gt;. It was observed that an increase in the contact rate between non-vaccinated susceptible individuals and infectious individuals significan","PeriodicalId":53407,"journal":{"name":"Vacunas","volume":"27 2","pages":"Article 500508"},"PeriodicalIF":0.0,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147740108","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Implementation, impact of vaccination coverage and determinants of VZV immunization in people living with HIV: The HIV-ZoVax study","authors":"Ivorra-Gómez Silvia ,&nbsp;Jover-Díaz Francisco ,&nbsp;De Gea-Velázquez Teresa ,&nbsp;Delgado-Sánchez Elisabet ,&nbsp;Peris-García Jorge ,&nbsp;Esteve-Atiénzar Pedro","doi":"10.1016/j.vacun.2026.500632","DOIUrl":"10.1016/j.vacun.2026.500632","url":null,"abstract":"<div><h3>Background</h3><div>Shingles remains a significant cause of morbidity in people living with HIV despite advances in antiretroviral therapy. The recombinant zoster vaccine (RZV) is recommended for this population, yet vaccine coverage and adherence remain suboptimal. This study evaluated the implementation, coverage, and determinants of varicella-zoster virus vaccination in a Spanish cohort of HIV patients.</div></div><div><h3>Methods</h3><div>We retrospectively analyzed adults with chronic HIV infection followed at an infectious diseases unit in Alicante from January 2022 to March 2025. Sociodemographic, clinical, and vaccination data were extracted from electronic health records. Vaccination status was classified as complete, partial, or unvaccinated. Factors associated with full vaccination were assessed using multivariate analysis.</div></div><div><h3>Results</h3><div>Among 198 eligible patients, 37.4% completed the full vaccination schedule, 4% were partially vaccinated, and 46% remained unvaccinated. Primary reasons for incomplete vaccination included lack of referral and loss to follow-up. Referral to preventive medicine services and attendance at scheduled appointments were the strongest independent predictors of completing vaccination. No significant associations were observed with age, sex, CD4<!--> <!-->+ counts, viral load, or comorbidity burden.</div></div><div><h3>Conclusions</h3><div>Although vaccination coverage has improved compared to previous reports, significant gaps persist among people living with HIV in our clinic setting. These gaps are mainly due to systemic barriers in patient referral and retention within the vaccination program. Targeted interventions are needed to optimize vaccination pathways, enhance patient follow-up, and strengthen coordination between healthcare providers and patients to increase full immunization rates and reduce shingles-related morbidity in this vulnerable population.</div></div>","PeriodicalId":53407,"journal":{"name":"Vacunas","volume":"27 2","pages":"Article 500632"},"PeriodicalIF":0.0,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Causality assessment of adverse events following immunization “AEFIs” linked to COVID-19 vaccines: clinical cases","authors":"Ibtissem Nour El Houda Bekhti ,&nbsp;Derouicha Matmour ,&nbsp;Wafaa Yakoub El Kraldia ,&nbsp;Hadjer Larachi ,&nbsp;Yassine Merad ,&nbsp;Houari Toumi","doi":"10.1016/j.vacun.2025.500505","DOIUrl":"10.1016/j.vacun.2025.500505","url":null,"abstract":"<div><h3>Introduction and objective</h3><div>To counter the risk posed by COVID-19, vaccines were developed. However, these vaccines are not without dangers. Vaccinovigilance studies have demonstrated their involvement in a number of transient benign manifestations, which have been added to the SPC (summary of product characteristics) of these vaccines, as well as in rare cases of severe Adverse Events Following Immunization “AEFIs”. The aim of our study was to examine the cases of abnormal or serious events that occurred during the survey and to assess the likelihood of a causal link between them and the covid vaccination 19.</div></div><div><h3>Methods</h3><div>This is a descriptive cross-sectional study conducted over a 6-month period from October 2021 to April 2022 in Algeria. Patient testimonials were collected via a questionnaire drafted in two languages: French and Arabic, and used in the form of a paper form and an electronic questionnaire to be completed online. The questions are therefore inspired by the “checklist” used in this method. It follows four steps: Eligibility, Checklist, Algorithm and Classification.</div></div><div><h3>Results</h3><div>We found that there is considerable inter-individual variability in terms of body response to vaccination. While it is true that the adverse effects mentioned in vaccine SPCs are found frequently in vaccinated patients, there are also patients who experienced no abnormalities at all after vaccination.</div><div>We also found that among the cases of severe or habitual AEFIs we studied, some had a highly probable causal link with vaccination, whereas some were possibly related to the subjects' exposure to factors other than vaccines.</div></div><div><h3>Conclusion</h3><div>It is difficult to predict how a human body will react to vaccination, but ongoing vaccinovigilance procedures seek to perfect the knowledge we have about these recently developed vaccines.</div></div>","PeriodicalId":53407,"journal":{"name":"Vacunas","volume":"27 2","pages":"Article 500505"},"PeriodicalIF":0.0,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147740107","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Clesrovimab: un nuevo monoclonal destinado a la prevención del virus respiratorio sincitial en la población lactante","authors":"Jordi Reina,&nbsp;Nerea Espinosa","doi":"10.1016/j.vacun.2025.500504","DOIUrl":"10.1016/j.vacun.2025.500504","url":null,"abstract":"&lt;div&gt;&lt;div&gt;En 2023 se comercializó en España el anticuerpo monoclonal nirsevimab, dirigido específicamente frente al «sitio cero (Ø)» de la conformación de prefusión (preF) de la proteína F del virus respiratorio sincitial (VRS). La eficacia demostrada de este anticuerpo monoclonal impulsó la investigación de nuevas dianas antigénicas en dicha proteína del VRS. Clesrovimab (RB1) es un anticuerpo monoclonal humano tipo IgG kappa dirigido contra el sitio IV del VRS, expuesto tanto en la forma preF como en la posF. Su detección en secreciones nasales ha mostrado capacidad neutralizante frente al VRS, correlacionada con la concentración nasal, que representa entre el 1,4 y 3,3% de la concentración sérica. A los 5 meses de la inmunización, clesrovimab mostró una reducción en la incidencia y la gravedad de los síntomas del tracto respiratorio inferior asociados al VRS del 88%, en la hospitalización por VRS del 84,2% y en la hospitalización grave del 90,9%, tras una dosis de 100 mg. En junio de 2025, la FDA aprobó el anticuerpo monoclonal Enflonsia™ (clesrovimab-cfor, Merck &amp; Co.), producido por la recombinación genética en células de ovario de hámster chino, para la prevención de las infecciones del tracto respiratorio inferior causadas por el VRS en lactantes nacidos durante o expuestos a su primera temporada de circulación de VRS (menores de 8 meses). De acuerdo con los diferentes ensayos clínicos disponibles, se trata de un anticuerpo monoclonal de vida media prolongada, diseñado para proporcionar una protección específica, directa, rápida y duradera (al menos 5 meses) con una única dosis de 105 mg administrada por vía intramuscular, independientemente del peso del lactante.&lt;/div&gt;&lt;/div&gt;&lt;div&gt;&lt;div&gt;In 2023, the monoclonal antibody nirsevimab, specifically targeting the “site zero (Ø)” of the pre-fusion (preF) form of the RSV F protein, was introduced in Spain. The proven efficacy of this monoclonal antibody has led further researcher into novel antigenic targets on the RSV F protein. Clesrovimab (RB1) is a human IgG kappa monoclonal antibody directed against site IV of RSV, which is exposed in both the preF and postF conformations. The presence of clesrovimab in nasal secretions has shown RSV-neutralizing activity, which correlates with its nasal concentration that represents between 1.4% and 3.3% of serum concentration. Five months after immunization, clesrovimab has shown a reduction of the incidence and severity of RSV-associated lower respiratory tract symptoms by 88%, the incidence of RSV-related hospitalization by 84.2%, and the incidence of severe hospitalization by 90.9% following a single 100 mg dose. In June 2025, the FDA approved the monoclonal antibody Enflonsia™ (clesrovimab-cfor; Merck &amp; Co.), produced by genetic recombination in Chinese hamster ovary cells, for the prevention of lower respiratory tract infections caused by RSV in infants born during or entering their first RSV season (aged &lt;&lt;!--&gt; &lt;!--&gt;8 months). Based on variou","PeriodicalId":53407,"journal":{"name":"Vacunas","volume":"27 1","pages":"Article 500504"},"PeriodicalIF":0.0,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147420191","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Global, regional, and subnational trends in typhoid fever burden from 1990 to 2021: an analysis of global burden of disease data","authors":"Z. Ahsan ,&nbsp;H. Mehmood ,&nbsp;H. Ali ,&nbsp;M. Ahsan","doi":"10.1016/j.vacun.2025.500503","DOIUrl":"10.1016/j.vacun.2025.500503","url":null,"abstract":"<div><h3>Introduction</h3><div>Typhoid fever remains a significant global health concern, particularly in low- and middle-income countries (LMICs). The study aimed to assess temporal trends in typhoid fever burden at the global, South Asian, and provincial levels in Pakistan from 1990 to 2021 using data from the Global Burden of Disease (GBD) study.</div></div><div><h3>Methods</h3><div>An ecological analysis was conducted using GBD data to examine trends in age-standardized mortality rates (ASMRs) and disability-adjusted life years (DALYs) attributable to typhoid fever. Temporal changes were analyzed globally, across South Asia, and within Pakistan's provinces using average percent change (APC) calculations and Joinpoint regression.</div></div><div><h3>Results</h3><div>Globally and in South Asia, typhoid-related age-standardized mortality rates (ASMRs) and disability-adjusted life years (DALYs) declined substantially from 1990 to 2021. The global ASMR decreased from 3.22 to 1.31 per 100,000, while DALYs dropped from 247.95 to 101.09 per 100,000. In South Asia, ASMR fell from 9.80 to 3.42, and DALYs from 728.56 to 260.27 per 100,000. Within Pakistan, national ASMR declined from 6.42 to 3.08, and DALYs from 483.43 to 238.58 per 100,000. Provincial trends revealed marked disparities: Punjab and Khyber Pakhtunkhwa exhibited the greatest reductions, whereas Sindh showed slower progress, with the smallest decline in both mortality and DALYs.</div></div><div><h3>Conclusion</h3><div>Despite encouraging global progress, persistent subnational disparities in Pakistan highlight the need for targeted public health interventions. Expanding vaccine coverage, enhancing antimicrobial resistance surveillance, and improving water, sanitation, and hygiene (WASH) infrastructure are essential to further reducing typhoid burden and addressing regional inequities.</div></div>","PeriodicalId":53407,"journal":{"name":"Vacunas","volume":"27 1","pages":"Article 500503"},"PeriodicalIF":0.0,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147420192","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adult contributions to measles transmission in children: Evidence from a two-age model with implications for vaccination strategies in elimination-phase settings","authors":"T.S. Faniran ,&nbsp;M.O. Adewole","doi":"10.1016/j.vacun.2025.500629","DOIUrl":"10.1016/j.vacun.2025.500629","url":null,"abstract":"<div><div>Measles elimination depends on identifying who drives transmission and how cross-age interactions shape outbreaks. During the 2018–2019 New York City outbreak, preschool children were the primary spreaders, but the amplifying role of adults remained unclear. We developed and calibrated a two-age SEIR model to cumulative incidence data, estimated age-specific transmission parameters using nonlinear least squares, and analyzed equilibrium behavior and global stability under the threshold condition, <span><math><msub><mi>R</mi><mn>0</mn></msub><mo>=</mo><mn>1</mn></math></span>. We also evaluated vaccination strategies, including intensified child vaccination, suspended adult vaccination, and control-based interventions, together with global sensitivity and uncertainty analyses. The fitted model reproduced observed patterns accurately (<span><math><msup><mi>R</mi><mn>2</mn></msup><mo>=</mo><mn>0.94</mn></math></span> for children; <span><math><msup><mi>R</mi><mn>2</mn></msup><mo>=</mo><mn>0.84</mn></math></span> for adults). The initial reproduction number was <span><math><msub><mi>R</mi><mn>0</mn></msub><mo>=</mo></math></span> <span><math><mn>1.10</mn></math></span>, indicating sustained transmission. Stability analysis showed that the disease-free equilibrium is globally stable when <span><math><msub><mi>R</mi><mn>0</mn></msub><mo>&lt;</mo><mn>1</mn><mo>,</mo></math></span> and the endemic equilibrium is globally attracting when <span><math><msub><mi>R</mi><mn>0</mn></msub><mo>&gt;</mo><mn>1</mn><mo>.</mo></math></span> Although child-to-child transmission dominated, adults contributed a steady minority of new child infections (about 8%). Sensitivity analysis identified <span><math><msub><mi>β</mi><mi>CC</mi></msub></math></span> (child<!--> <!-->→<!--> <!-->child) as the strongest determinant of outbreak size and <span><math><msub><mi>β</mi><mi>CA</mi></msub></math></span> (adult<!--> <!-->→<!--> <!-->child) as the main driver of spillover; a 20% increase in <span><math><msub><mi>β</mi><mi>CA</mi></msub></math></span> nearly doubled the adult share of child infections. Vaccination simulations showed that balanced age-wide vaccination suppresses transmission more effectively than child-only intensification, which leaves an unprotected adult reservoir capable of reseeding infections. Increasing child coverage reduced child and adult cases by 3–4% and 2–3%, while adult boosters produced smaller but meaningful reductions in spillover. These results indicate that adults play a measurable secondary role in sustaining transmission. Effective elimination strategies must therefore maintain <span><math><msub><mi>R</mi><mn>0</mn></msub><mo>&lt;</mo><mn>1</mn></math></span> while preserving immunity across both age groups.</div></div>","PeriodicalId":53407,"journal":{"name":"Vacunas","volume":"27 1","pages":"Article 500629"},"PeriodicalIF":0.0,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145978225","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}