Dengue Management Research Articles

Knowledge and Perceptions about Diagnosis, Clinical Management, and Prevention of Dengue Fever among Physicians during the 2023 Outbreak: A Cross-Sectional Study in Peru.

The objective of this study was to evaluate the knowledge level and perception of dengue fever management among Peruvian physicians and to determine the factors associated with higher knowledge. We conducted an analytical cross-sectional study based on an online survey. To evaluate the factors associated with a high level of knowledge (≥70% of correct answers), we used crude (cPR) and adjusted (aPR) prevalence ratios by the Poisson regression model. Of 359 respondents (median age: 33 years; male: 56.5%), 78.8% achieved a high level of knowledge. Multivariable analysis showed an independent association with having read the Peruvian clinical practice guidelines for dengue management (aPR: 1.29; 95% CI: 1.12-1.49), having experience in treating patients (aPR: 1.32; 95% CI: 1.03-1.68), and having treated cases frequently (aPR: 1.22; 95% CI: 1.02-1.46). Residing in the eastern macroregion (aPR: 0.83; 95% CI: 0.71-0.97) was associated with a low level of knowledge. In conclusion, Peruvian physicians had a high level of knowledge about dengue fever. This was associated with having clinical experience in dengue management. However, given the low level of knowledge in the eastern macroregion, educational campaigns are necessary in this area.

SMART DENGUE CONTROL

This research presents a novel approach to combating dengue by integrating Biological Control methods with Artificial Intelligence (AI). The objective of the study is to reduce the Aedes aegypti mosquito population and decrease dengue transmission through sustainable strategies. A comprehensive research methodology was used, involving extensive literature review, case studies, and data analysis to identify the main factors driving the high incidence of dengue in Brazil. The research applied AI tools to analyze epidemiological, meteorological, and environmental data, allowing for early outbreak predictions and targeted interventions. AI-enhanced surveillance systems were also employed to monitor mosquito populations and identify breeding sites more accurately. These strategies were combined with biological control methods, such as using natural predators and genetically modified mosquitoes, to manage mosquito populations effectively. The study demonstrate that the integration of AI and biological control can significantly improve the efficiency, accuracy, and sustainability of dengue control measures. The study concludes that this data-driven approach, when adapted to local contexts, can reduce reliance on chemical pesticides and offer a more resilient framework for long-term dengue management.

Atopic Dermatitis Immune Dysregulation as Dengue Predisposing Factor.

The immune response is important in dengue's clinical manifestation, and the immune dysregulation in Atopic Dermatitis (AD) can permit immune evasion by viruses. There have been many studies describing the immune response in AD and the pathomechanism of dengue, but AD as a predisposing factor for dengue and its severity have not been much discussed. This review investigates how immune dysregulation in AD may be a predisposing factor for Dengue and its severe outcomes. We conducted a comprehensive analysis of studies from the past decade, focusing on dendritic cells (DCs), macrophages, mast cells (MCs), Innate Lymphoid Cell 2 (ILC-2), Natural Killer (NK) cells, interferon (IFN), interleukin (IL) 4, IL-13, and T helper (Th) 2 in AD patients with healthy subject as a comparison, using databases PubMed, Science Direct, and Google Scholar. We got 44 articles that met inclusion criteria. From those articles, we resumed that moderate and severe AD patients' immune profiles showed increased DC, MCs, M2 macrophage, NK cells, and ILC2 in the lesional and non-lesional skin, decreased DC and NK cells in peripheral blood, alteration cytotoxicity of NK cells,Th2-skewed adaptive immune response in lesional and non-lesional skin, and peripheral blood. Increased DC, M2 macrophage, and MCs provide target cells for Dengue virus (DENV) replication. Alteration cytotoxicity of NK cells, ILC2, and Th2 skewed immune response facilitated immune evasion by DENV. The innate and adaptive immune dysregulation in moderate and severe AD provides DENV target cells and facilitates virus immune evasion that can be a predisposing factor for dengue and severe dengue. Further research is recommended to clarify the association between AD and the incidence of dengue and severe dengue because this can be a consideration in determining the prognosis and management of Dengue.

The Impact of Climate on Human Dengue Infections in the Caribbean.

Climate change is no longer a hypothetical problem in the Caribbean but a new reality to which regional public health systems must adapt. One of its significant impacts is the increased transmission of infectious diseases, such as dengue fever, which is endemic in the region, and the presence of the Aedes aegypti mosquito vector responsible for transmitting the disease. (1) Methods: To assess the association between climatic factors and human dengue virus infections in the Caribbean, we conducted a systematic review of published studies on MEDLINE and Web of Science databases according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria. (2) Results: In total, 153 papers were identified, with 27 studies selected that met the inclusion criteria ranging from the northern and southern Caribbean. Rainfall/precipitation and vapor pressure had a strong positive association with dengue incidence, whereas the evidence for the impact of temperatures was mixed. (3) Conclusions: The interaction between climate and human dengue disease in the Caribbean is complex and influenced by multiple factors, including waste management, infrastructure risks, land use changes, and challenged public health systems. Thus, more detailed research is necessary to understand the complexity of dengue within the wider Caribbean and achieve better dengue disease management.

A study to assess the knowledge and practice of women regarding dengue in rural area of Meerut, Uttar Pradesh, India

Background: Dengue affects 390 million people yearly. 70% global disease burden is from Asia. Every fourth person infected with dengue get sick and about one in 20 people infected with dengue develop severe dengue. Aim of this study was to assess the knowledge and practice of women regarding dengue in rural area of Meerut, U.P. Methods: A descriptive survey was done to conduct this study. Multistage random sampling was used to select study area and participants. Data has been collected from 50 participants. Self-developed knowledge questionnaire and checklist was prepared to measure knowledge and practices of people regarding knowledge and practices. Result: Most of the participants were between age group 18-23 years and were homemakers. All participants had previous knowledge about Dengue and source of information was TV/radio/newspaper for most of the participants. In this study 74% of participants has moderately adequate knowledge level, 16% had adequate and 10% had inadequate knowledge level. In regard to practices, 72% participant have satisfactorily practices, 20% had moderately satisfactorily practices and of 8 % participant non satisfactorily practices regarding prevention and management of dengue. Conclusion: Majority of participants had adequate knowledge and satisfactorily practices but still it is needed to organize awareness campaign to disseminate knowledge regarding dengue to community people of all age groups to improve their practices in this regard.

Effects of the oxoaporphine alkaloid hernandonine on dengue virus. Evidence for its mechanisms of action

BackgroundDengue, caused by the dengue virus (Orthoflavivirus dengue, encompassing DENV types 1-4), is a member of the Flaviviridae family. The symptoms of dengue range from subclinical or mild manifestations to potentially fatal complications. The management of severe dengue is exceptionally challenging due to the absence of effective antiviral medications. In this context, natural products, whether in the form of pure compounds or standardized plant extracts, have emerged as a promising source for the development of novel antiviral therapeutics. Hernandonine, an oxoaporphine alkaloid found in Hernandia nymphaeifolia (C. Presl) Kubitzki. serves both as a metabolite and an inhibitor of human immunodeficiency virus type 1 (HIV-1) integrase. PurposeThis study investigated the ability of hernandonine to inhibit DENV infection and explored its potential mechanisms. Study designTo assess the in vitro anti-DENV activity, cells or induced pluripotent stem cell (iPSC)-derived cerebral organoids were exposed to hernandonine before or after infection with DENV. Along with hernandonine, the endocytosis modulators, genistein, wortmannin, Methyl-β-cyclodextrin (MβCD) and lovastatin, were used in the assays. MethodsThe DENV infectivity and virion production in cells or cerebral organoids treated with compounds were determined. Various methods, including cell and cerebral organoids imaging, protein and gene detection were conducted to explore their antiviral mechanisms. ResultsThe results revealed notable antiviral properties of hernandonine, particularly in inhibiting DENV during the early stages of infection. Mechanistic analysis demonstrated that, akin to genistein, wortmannin, methyl-β-cyclodextrin (MβCD), and lovastatin, hernandonine exerted an influence on cholesterol-rich lipid rafts. It also restrained the pseudopodial movement ability of cells, potentially through the downregulation of cytoskeleton and endocytosis regulatory genes or protein expression. Moreover, hernandonine's virucidal activity was demonstrated. Hernandonine's inhibition of DENV infection was further validated in a disease-relevant iPSC-derived cerebral organoids model, a novel DENV-2 infection system worthy of further application. ConclusionThis study evidenced the potential of hernandonine as a novel candidate in the fight against DENV infection.

Foveolitis with fever: An optical tomography biomarker for dengue maculopathy

We report a case of a 25-year-old boy presenting to an ophthalmologist with unilateral foveolitis associated with fever. After a thorough ocular clinical examination and with the aid of the characteristic finding of foveolitis on optical coherence tomography, a probable clinical diagnosis of dengue fever maculopathy secondary to systemic dengue was made. The patient was referred to the physician for systemic management of dengue. On laboratory investigation, the patient was found to be seropositive for dengue virus. The patient was treated with topical and systemic steroids from our end besides receiving general symptomatic care at the physician’s end. This case highlights the role of an ophthalmologist in promptly diagnosing and managing dengue-related ocular complications in collaboration with a physician.

Shock Management and Hemodynamic Monitoring of Severe Dengue with Fluid Overload: A Case Report

Shock Management and Hemodynamic Monitoring of Severe Dengue with Fluid Overload: A Case Report

A Cross-Sectional Study on Bedside Abdominal Ultrasound Findings as a Diagnostic and Prognostic Tool in Dengue Fever in Manipal Hospital, Bengaluru, India.

Background Dengue fever poses a significant health burden globally, particularly in tropical and subtropical regions. Early diagnosis and effective management are crucial in reducing morbidity and mortality associated with the disease. Bedside abdominal ultrasound has emerged as a promising tool for assessing dengue patients, providing real-time imaging of abdominal organs, and aiding clinical decision-making. Materials and methods This cross-sectional study was conducted in55 adult emergency departments of Manipal Hospital, Bengaluru, from March 2017 to March 2018. Adult patients presenting with signs and symptoms suggestive of dengue fever were included. Clinical data, laboratory investigations, and bedside abdominal ultrasound findings were systematically recorded and analyzed using appropriate statistical methods. Results Descriptive statistics revealed characteristic clinical measurements and symptom ratings observed in dengue fever patients. Frequency distributions highlighted common symptoms encountered, while statistical analyses demonstrated significant associations between ultrasonic parameters, disease severity, and outcomes. The study found notable correlations between ultrasonic findings and dengue severity levels, emphasizing the potential of bedside ultrasound as a diagnostic and prognostic tool. Conclusion Bedside abdominal ultrasound shows promise as a valuable adjunctive tool in assessing dengue fever patients. The significant associations between ultrasonic parameters and disease severity suggest its utility in risk stratification and guiding clinical management decisions. Incorporating bedside ultrasound into routine practice may improve patient care and outcomes in dengue fever management. Further research is warranted to validate these findings and explore additional bedside ultrasound applications in dengue fever diagnosis and prognosis.

DENGUE MANAGEMENT THROUGH MOSQUITO CONTROL: ASPHYXIATION TECHNIQUES AND HOMEMADE REPELLENTS FOR SKIN PROTECTION

Mosquito-borne diseases pose significant health challenges globally, particularly in regions such as Bangladesh where chikungunya and dengue have been prevalent in recent years. These diseases are transmitted through the bites of infected mosquitoes, which breed in stagnant water. Common mosquito-borne diseases include chikungunya, dengue, malaria, and Zika virus, among others. Efforts to control mosquito populations have included the destruction of breeding sites, the application of larvicides, and more recently, the use of Bacillus thuringiensis israelensis (BTI) in Dhaka. While these measures have helped manage chikungunya, dengue remains a persistent issue despite ongoing control efforts. This paper explores innovative mosquito control strategies, focusing on asphyxiation techniques to reduce mosquito populations and the use of homemade repellents for personal protection against mosquito bites. The effectiveness of these methods in the context of dengue management is critically examined.

Liver involvement in dengue: A systematic review.

Liver involvement is an unusual yet frequently overlooked dengue complication. Pivotal for an efficient clinical management, the early diagnosis of dengue-associated liver involvement relies on an accurate description of its clinical and biological characteristics, its prognosis factors, its association with severe dengue and its clinical management. We conducted a systematic review by searching PubMed and Web of Science databases for original case reports, cohort and cross-sectional studies reporting the clinical and/or biological features of dengue-associated liver involvement. The study was registered in PROSPERO (CRD42021262657). Of the 2552 articles identified, 167 were included. Dengue-associated liver involvement was characterised by clinical features including abdominal pain, hepatomegaly, jaundice, nausea/vomiting, and an echogenic liver exhibiting hepatocellular necrosis and minimal inflammation. Elevated Aspartate Aminotransferase and Alanine Aminotransferase but also elevated bilirubin, Alkaline Phosphatase, gamma-glutamyl transferase, increased International Normalised Ratio, creatinine and creatine kinase, lower albumin and prolonged prothrombin and activated partial thromboplastin time were prevalent in dengue-associated liver involvement. Cardiovascular and haematological systems were frequently affected, translating in a strong association with severe dengue. Liver involvement was more common in males and older adults. It was associated with dengue virus serotype-2 and secondary infections. Early paracetamol intake increased the risk of liver involvement, which clinical management was mostly conservative. In conclusion, this systematic review demonstrates that early monitoring of transaminases, clinical assessment, and ultrasound examination allow an efficient diagnosis of dengue-associated liver involvement, enabling the early identification and management of severe dengue.

Dengue in Wardha City: Addressing Social and Clinical Challenges

Dengue fever, a major public health concern in tropical and subtropical areas, is a critical issue in Wardha city. The purpose of this study was to analyze Wardha inhabitants’ awareness, knowledge, and habits about dengue illness. The survey, which took place between November 2023 and April 2024, used a structured questionnaire and was delivered to a representative sample of 50 participants from various wards of the city. The questionnaire inquired about respondents’ knowledge of dengue symptoms, mechanisms of transmission, preventative measures, and attitudes toward local dengue control initiatives. Preliminary data show that, while many locals are aware of dengue and its symptoms, there are significant gaps in knowledge about effective preventative techniques, as well as widespread misunderstandings regarding transmission. The poll also preventative measures. Furthermore, the survey found diverse degrees of community engagement in dengue management operations, with many respondents advocating for more thorough and accessible teaching campaigns. These findings show the critical need for targeted educational initiatives and increased community engagement in Wardha city to improve dengue prevention and control. Public health experts and politicians are encouraged to use these findings to create and execute more effective, context-specific dengue control measures.

The Efficacy of Montelukast in Reducing the Risk of Warning Signs and Subsequent Dengue Shock Syndrome in Adult Dengue Fever Patients.

Dengue fever continues to pose significant health challenges globally, with recent outbreaks in Bihar, India, prompting a search for effective therapeutic interventions. This study assesses the effectiveness of Montelukast, traditionally used for asthma, in mitigating the severity of dengue fever symptoms and its progression to dengue shock syndrome (DSS). To evaluate the impact of Montelukast on the prevalence of dengue warning signs and the incidence of DSS in adult patients. A prospective observational study was conducted at the Indira Gandhi Institute of Medical Sciences(IGIMS), Patna, India, from August 2022 to October 2023, enrolling 500 patients diagnosed with dengue fever. Participants were divided into two groups. About 250 were treated with Montelukast and 250 received standard care. Outcomes measured included the incidence of warning signs, DSS, length of hospital stay, and 30-day mortality. The Montelukast group exhibited a 24% lower prevalence of dengue warning signs compared to the control group, with 90 out of 250 patients (36%) in the Montelukast group versus 150 out of 250 patients (60%) in the control group (p < 0.001). The incidence of DSS was significantly reduced in the Montelukast group, with 4 out of 250 patients (1.6%) compared to 21 out of 250 patients (8.4%) in the control group (odds ratio: 0.178, p < 0.001). Furthermore, Montelukast users experienced shorter hospital stays (average 4.52 days vs. 6.54 days, T-statistic: -7.59, p = 1.58×10-13) and a reduced 30-day mortality rate, with 5 out of 250 patients (2%) in the Montelukast group versus 12 out of 250 patients (5%) in the control group (p < 0.03). Montelukast significantly lowers the incidence of dengue warning signs and DSS, shortens hospital stays, and decreases mortality rates among dengue patients, supporting its potential integration into existing dengue treatment protocols. This study highlights the need for further clinical trials to confirm these findings and fully understand the therapeutic mechanisms of Montelukast in dengue management.

Dynamics of emergence and genetic diversity of dengue virus in Reunion Island from 2012 to 2022.

Dengue is a major public health concern in Reunion Island, marked by recurrent epidemics, including successive outbreaks of dengue virus serotypes 1 and 2 (DENV1 and DENV2) with over 70,000 cases confirmed since 2017. In this study, we used Oxford Nanopore NGS technology for sequencing virologically-confirmed samples and clinical isolates collected between 2012 and 2022 to investigate the molecular epidemiology and evolution of DENV in Reunion Island. Here, we generated and analyzed a total of 499 DENV1, 360 DENV2, and 18 DENV3 sequences. By phylogenetic analysis, we show that different genotypes and variants of DENV have circulated in the past decade that likely originated from Seychelles, Mayotte and Southeast Asia and highly affected areas in Asia and Africa. DENV sequences from Reunion Island exhibit a high genetic diversity which suggests regular introductions of new viral lineages from various Indian Ocean islands. The insights from our phylogenetic analysis may inform local health authorities about the endemicity of DENV variants circulating in Reunion Island and may improve dengue management and surveillance. This work emphasizes the importance of strong local coordination and collaboration to inform public health stakeholders in Reunion Island, neighboring areas, and mainland France.

The innovation of Wolbachia mosquito technology to control dengue hemorrhagic fever

Wolbachia is a bacterium that generally occurs naturally in 50% of insect species, lives in insect cells, and is passed from one generation to the next through insect eggs. Wolbachia in the mosquito's body can inhibit the replication of the Dengue virus or other viruses. Based on the Decree of the Minister of Health of the Republic of Indonesia Number 1341 concerning the Implementation of the Pilot Project for the Implementation of Wolbachia as a Dengue Management Innovation, the application of this technology was carried out in five cities, namely Semarang City, West Jakarta, Bandung City, Kupang City, and Bontang City. The effectiveness of Wolbachia itself has been proven and researched since 2011, when it was conducted in Yogyakarta. As a result, Wolbachia was proven to reduce dengue fever cases by up to 77% and reduce the proportion of hospital admissions by 86%. This method of spreading Wolbachia mosquitoes in several cities will reduce local transmission of infection in those areas. This reduction in local transmission of dengue infection occurs both in the rainy and dry seasons. Scientifically, the success of the Wolbachia method is apparent, but the controversy is due to confused information circulating, giving rise to concern among the public. Vector control using Wolbachia is an alternative disease control method that uses mosquito vectors and is quite effective. However, the application of Wolbachia in the community must be monitored continuously to determine its impact on humans, local mosquitoes, and the ecosystem.

Molecular Detection and Genotyping of Dengue Viruses: Current Techniques and Future Prospect

The Dengue virus is a prevalent mosquito-borne disease, and its global incidence has been steadily increasing due to the favorable environmental conditions that promote mosquito breeding, primarily influenced by rising temperatures. Bangladesh has been particularly hard-hit by an intense and ongoing outbreak, resulting in a surge of cases and fatalities. Effective management of this disease necessitates the implementation of robust public health measures, including rigorous surveillance and early diagnosis. While serological tests are commonly employed in clinical diagnosis, molecular methods hold a critical role in identifying the specific Dengue virus strain, thereby contributing to a more comprehensive understanding of disease severity. This article serves as an extensive review, delving into various molecular testing techniques employed for both surveillance and clinical diagnosis. It offers valuable insights for research and clinical laboratories engaged in the detection of Dengue virus RNA in mosquitoes, environmental samples, and clinical specimens. The methods covered encompass a spectrum of approaches, including conventional PCR, isothermal amplification, real-time RT-PCR, Sanger sequencing, and whole-genome sequencing, providing a holistic overview of the available techniques. These methods play pivotal roles in clinical diagnosis, outbreak analysis, vector surveillance, and vaccine development. Furthermore, the article underscores the importance of integrating these techniques into existing healthcare systems, emphasizing their significance in ensuring precise dengue diagnostics to enhance the efficiency of disease management. These molecular methods are indispensable tools that contribute to accurate diagnosis, enable effective outbreak investigation, facilitate vector surveillance, and support vaccine preparation, thereby enhancing the overall management and control of dengue, ultimately working toward mitigating its impact on public health.&#x0D; Bangladesh J Microbiol, Volume 40, Number 1, June 2023, pp 41-49

Optimising the surveillance of Aedes aegypti in Brazil by selecting smaller representative areas within an endemic city.

Arboviruses, such as dengue (DENV), zika (ZIKV), and chikungunya (CHIKV), constitute a growing urban public health threat. Focusing on Aedes aegypti mosquitoes, their primary vectors, is crucial for mitigation. While traditional immature-stage mosquito surveillance has limitations, capturing adult mosquitoes through traps yields more accurate data on disease transmission. However, deploying traps presents logistical and financial challenges, demonstrating effective temporal predictions but lacking spatial accuracy. Our goal is to identify smaller representative areas within cities to enhance the early warning system for DENV outbreaks. We created Sentinel Geographic Units (SGUs), smaller areas of 1 km2 within each stratum, larger areas, with the aim of aligning the Trap Positivity Index (TPI) and Adult Density Index (ADI) with their respective strata. We conducted a two-step evaluation of SGUs. First, we examined the equivalence of TPI and ADI between SGUs and strata from January 2017 to July 2022. Second, we assessed the ability of SGU's TPI and ADI to predict DENV outbreaks in comparison to Foz do Iguaçu's Early-Warning System, which forecasts outbreaks up to 4 weeks ahead. Spatial and temporal analyses were carried out, including data interpolation and model selection based on Akaike information criteria (AIC). Entomological indicators produced in small SGUs can effectively replace larger sentinel areas to access dengue outbreaks. Based on historical data, the best predictive capability is achieved 2 weeks after infestation verification. Implementing the SGU strategy with more frequent sampling can provide more precise space-time estimates and enhance dengue control. The implementation of SGUs offers an efficient way to monitor mosquito populations, reducing the need for extensive resources. This approach has the potential to improve dengue transmission management and enhance the public health response in endemic cities.

Using Computational Simulations Based on Fuzzy Cognitive Maps to Detect Dengue Complications.

Dengue remains a globally prevalent and potentially fatal disease, affecting millions of people worldwide each year. Early and accurate detection of dengue complications is crucial to improving clinical outcomes and reducing the burden on healthcare systems. In this study, we explore the use of computational simulations based on fuzzy cognitive maps (FCMs) to improve the detection of dengue complications. We propose an innovative approach that integrates clinical data into a computational model that mimics the decision-making process of a medical expert. Our method uses FCMs to model complexity and uncertainty in dengue. The model was evaluated in simulated scenarios with each of the dengue classifications. These maps allow us to represent and process vague and fuzzy information effectively, capturing relationships that often go unnoticed in conventional approaches. The results of the simulations show the potential of our approach to detecting dengue complications. This innovative strategy has the potential to transform the way clinical management of dengue is approached. This research is a starting point for further development of complication detection approaches for events of public health concern, such as dengue.

Assessing the impact of emergency measures in varied population density areas during a large dengue outbreak

BackgroundThe patterns of dengue are affected by many factors, including population density and climate factors. Densely populated areas could play a role in dengue transmission due to increased human-mosquito contacts, the presence of more diverse and suitable vector habitats and breeding sites, and changes in land use. In addition to population densities, climatic factors such as temperature, relative humidity, and precipitation have been demonstrated to predict dengue patterns. To control dengue, emergency measures should focus on vector management. Most approaches to assessing emergency responses to dengue risks involve applying simulation models or describing emergency activities and the results of implementing those responses. Research using real-world data with analytical methods to evaluate emergency responses to dengue has been limited. This study investigated emergency control measures associated with dengue risks in areas with high and low population densities, considering their different control capacities. MethodologyData from the 2015 dengue outbreak in Kaohsiung City, Taiwan, were utilized. The government database provided information on confirmed dengue cases, emergency control measures, and climatic data. The study employed a distributed lag non-linear model (DLNM) to assess the effect of emergency control measures and their time lags on dengue risk. Principal findingsThe findings revealed that in areas with high population density, the absence of emergency measures significantly elevated the risks of dengue. However, implementing emergency measures, especially a higher number, was associated with lower risks. In contrast, in areas with low population density, the risks of dengue were only significantly elevated at the 1st week lag if no emergency control measures were implemented. When emergency activities were carried out, the risks of dengue significantly decreased only for the 1st week lag. ConclusionsOur findings reveal distinct exposure-lag-response patterns in the associations between emergency control measures and dengue in areas with high and low population density. In regions with a high population density, implementing emergency activities during a significant dengue outbreak is crucial for reducing the risk. Conversely, in areas of low population density, the necessity of applying emergency activities may be less pronounced. The implications of this study on dengue management could provide valuable insights for health authorities dealing with limited resources.

Age-specific case data reveal varying dengue transmission intensity in US states and territories.

Dengue viruses (DENV) are endemic in the US territories of Puerto Rico, American Samoa, and the US Virgin Islands, with focal outbreaks also reported in the states of Florida and Hawaii. However, little is known about the intensity of dengue virus transmission over time and how dengue viruses have shaped the level of immunity in these populations, despite the importance of understanding how and why levels of immunity against dengue may change over time. These changes need to be considered when responding to future outbreaks and enacting dengue management strategies, such as guiding vaccine deployment. We used catalytic models fitted to case surveillance data stratified by age from the ArboNET national arboviral surveillance system to reconstruct the history of recent dengue virus transmission in Puerto Rico, American Samoa, US Virgin Islands, Florida, Hawaii, and Guam. We estimated average annual transmission intensity (i.e., force of infection) of DENV between 2010 and 2019 and the level of seroprevalence by age group in each population. We compared models and found that assuming all reported cases are secondary infections generally fit the surveillance data better than assuming all cases are primary infections. Using the secondary case model, we found that force of infection was highly heterogeneous between jurisdictions and over time within jurisdictions, ranging from 0.00008 (95% CrI: 0.00002-0.0004) in Florida to 0.08 (95% CrI: 0.044-0.14) in American Samoa during the 2010-2019 period. For early 2020, we estimated that seropositivity in 10 year-olds ranged from 0.09% (0.02%-0.54%) in Florida to 56.3% (43.7%-69.3%) in American Samoa. In the absence of serological data, age-specific case notification data collected through routine surveillance combined with mathematical modeling are powerful tools to monitor arbovirus circulation, estimate the level of population immunity, and design dengue management strategies.