Epidemiology Of Dengue Fever Research Articles

Clinical characteristics and serotype association of dengue and dengue like illness in Pakistan.

Pakistan has been an endemic country for dengue virus since 1994, with a significant increase in cases reported in 2022 largely due to heavy rainfall and flooding. All four serotypes of the dengue virus (DENV) are present in Pakistan, with DENV 1 and DENV 2 being the most prevalent. The current study aims to explore the clinical presentations and features of dengue fever in a tertiary care hospital. We enrolled and studied 349 cases of suspected and confirmed dengue presenting for care at the Aga Khan University Hospital in Karachi between June 2021 and November 2023. Collected data on cases included clinical symptoms and laboratory results including qRT-PCR and serotype characterization. The majority of subjects enrolled (75%) had mild disease without warning signs, while 11% exhibited warning signs, 1.4% had severe dengue, and 12.6% had no dengue diagnosis. Patients with severe dengue (SD) had significantly higher levels of liver enzymes (AST and ALT) compared to those with non-severe dengue (NSD) (AST; p = 0.024 and ALT; p = 0.047). Additionally, a higher grade of thrombocytopenia was significantly associated with hospitalization (p = 0.0008), and prolonged illness (p = 0.03). Both Platelet (p < 0.0001) and WBC counts (p = 0.001) were significantly lower in dengue PCR-positive patients in comparison to Dengue PCR-negative. Among those tested for dengue serotypes, DENV 1 (34%) and DENV 2 (45%) emerged as the predominant serotypes, with mixed infections accounting for 17%. The sensitivity of q-RT PCR was found to be 87.25% and the specificity of 68.35%. qRT-PCR detected 43.5% of cases with viral fever initially screened negative by IgM or NS1. The epidemiology of dengue fever during a widespread outbreak in 2022 showed a predominance of DENV 1 and DENV 2 serotypes with milder phenotype of viral illness. Screening with rapid tests requires further confirmation by molecular assay in cases with dengue and dengue-like illness. The sensitivity of q-RT PCR using gold standard.

Advances in the Epidemiology, Pathogenesis, Diagnostic Methods, and Vaccine Development of Dengue Fever: A Comprehensive Review.

Dengue fever (DF) is a common mosquito-borne viral infection caused by any of the four dengue virus (DENV) serotypes. In recent years, the global incidence of DF has risen rapidly, which has widely threatened the health of millions of people in the United States, Southeast Asia, and the Western Pacific. The challenges for the prevention and control of DENV infection have become increasingly severe. Over the years, advances in the area of DF research have been continuously updating. In this review, we provide an updated and more in-depth overview of dengue epidemiology and pathogenesis, along with recent progress in diagnostic approaches (including methods to address cross-reactivity with other flaviviruses) and an expanded discussion of current dengue vaccine development, such as CYD-TDV (Dengvaxia), TV003/TV005, and the new TAK-003. This comprehensive perspective aims to offer references for the prevention, clinical diagnosis, and control of the disease.

Epidemiology of dengue fever in Somaliland: clinical features, and serological patterns from a retrospective study

BackgroundDengue fever is a significant global public health concern. However, its epidemiology in Somaliland remains poorly characterized. This study aimed to provide comprehensive data on the clinical presentation, demographic characteristics, and serological patterns of dengue fever in Somaliland.MethodsA retrospective analysis was conducted on 1,410 suspected dengue cases from public hospital laboratories in Somaliland between January and September 2024. Demographic data, clinical symptoms, and results of rapid diagnostic tests for dengue NS1 antigen and IgM antibodies were analyzed.ResultsOf the 1,410 suspected cases, 175 (12.41%) tested positive for dengue. The majority of the patients were male (60.57%) and aged 19–38 years (45.1%). Most cases were from urban areas (58.9%). Common symptoms included fever, vomiting, nausea (86.7%), GIT problems (86.12%) were the predominant symptom of patients. Serological testing revealed 84.57% NS1 positivity, 8.57% IgM positivity, and 6.85% positivity. The peak incidence was observed in June. Only 8.67% of the patients required hospitalization. Among these 8 cases (53.3%), as sever dengue and 7 (46.6%) were dengue with warning signs.ConclusionThis study provides initial insights into the epidemiology of dengue in Somaliland, though further research is needed to establish robust baseline data, highlighting its prevalence, particularly in urban adults. These preliminary findings suggest a potential need for enhanced surveillance and public health measures, pending confirmation from larger studies to address the emerging arboviral diseases in this region.

The Epidemiology of Dengue Fever: Comparative Analysis of Urban and Rural Transmission Dynamics

Background: Dengue fever poses a significant public health challenge, with over 3 billion individuals at risk globally. Traditionally, urban environments have been associated with higher dengue transmission rates, primarily due to dense populations and favorable conditions for Aedes aegypti proliferation. However, recent studies indicate a notable increase in dengue prevalence in rural areas. Methods: This study conducted a comprehensive literature review, employing Medical Subject Headings (MeSH) and keyword searches across multiple databases, including PubMed, Embase, and Web of Science. The analysis focused on defining rurality, examining transmission mechanisms, and comparing dengue incidence between urban and rural settings. Results: The findings reveal that dengue transmission risk in rural regions often equals or exceeds that in urban areas. Variability in definitions of rurality complicates the assessment of dengue dynamics. Many rural areas exhibit characteristics traditionally linked to urban settings, such as increased human mobility and altered land use patterns, which can enhance vector breeding sites and transmission rates. Conclusion: The study underscores the necessity for enhanced surveillance and understanding of dengue transmission in rural contexts. It emphasizes that while population size is relevant, environmental and infrastructural factors significantly influence dengue risk. Effective public health interventions must address these complexities, especially as rural areas increasingly contribute to dengue epidemiology.

Beyond the biting - limited impact of explicit mosquito dynamics in dengue models

Mathematical models play a crucial role in assisting public health authorities in timely disease control decision-making. For vector-borne diseases, integrating host and vector dynamics into models can be highly complex, particularly due to limited data availability, making system validation challenging. In this study, two compartmental models akin to the SIR type were developed to characterize vector-borne infectious disease dynamics. Motivated by dengue fever epidemiology, the models varied in their treatment of vector dynamics, one with implicit vector dynamics and the other explicitly modeling mosquito-host contact. Both considered temporary immunity after primary infection and disease enhancement in secondary infection, analogous to the temporary cross-immunity and the Antibody-dependent enhancement biological processes observed in dengue epidemiology. Qualitative analysis using bifurcation theory and numerical experiments revealed that the immunity period and disease enhancement outweighed the impact of explicit vector dynamics. Both models demonstrated similar bifurcation structures, indicating that explicit vector dynamics are only justified when assessing the effects of vector control methods. Otherwise, the extra equations are irrelevant, as both systems display similar dynamics scenarios. The study underscores the importance of using simple models for mathematical analysis, initiating crucial discussions among the modeling community in vector-borne diseases.

Dengue outbreaks in northern Nigeria: Evaluating the recommended Takeda vaccine and future prevention strategies.

Dengue fever, caused by the dengue virus (DENV), poses a significant public health challenge globally, with Nigeria experiencing sporadic outbreaks. A clear understanding of the dengue burden has not been achieved in Nigeria, just as in other African countries. Understanding the epidemiology and burden of dengue fever is essential for effective prevention and control strategies. This paper examines the recent dengue outbreaks in northern Nigeria, particularly in Sokoto state, and evaluates the recommended Takeda dengue vaccine (TDV) along with future prevention strategies. Despite limited surveillance and underreporting, dengue fever is endemic in Nigeria (with over 5 million cases and 5000 dengue-related deaths in 2023), with recent outbreaks indicating a growing concern. The TDV, a live attenuated tetravalent vaccine, has shown promise in preventing dengue fever, but challenges such as vaccine acceptance and accessibility need to be addressed. Global urbanization contributes to the disease's spread, which is influenced by factors such as population density, cultural beliefs, water storage practices, hygiene, and water supply accessibility. Future prevention strategies must focus on government intervention, community practices, and innovative vector control measures to mitigate the spread of DENV in Nigeria. This study will serve as a valuable reference for policymakers, researchers, and clinicians in the management and control of DENV in Nigeria and Africa as a whole.

Bifurcation analysis of a two infection SIR-SIR epidemic model with temporary immunity and disease enhancement

In this paper we study a two infection SIR-SIR compartmental model, considering biological features described in dengue fever epidemiology. Due to a progressive loss of protective antibodies there is waning immunity in the first infection stage and disease enhancement or protection effects by the second infection stage. Bifurcation analysis reveals two codim-2 bifurcations as organizing centers. The unfolding of a cusp bifurcation describes the transition of the disease-free equilibrium into an endemic equilibrium by varying a parameter. These equilibria allow an analytical solution with explicit expressions which allow for a full geometrical interpretation of the occurring bifurcations related to stationary dynamics. A Bogdanov-Takens point is the starting point in the parameter space where oscillatory endemic dynamics occurs including a homoclinic connection. These findings bring additional insights on biological mechanisms able to generate rich and complicated dynamical behavior in simple epidemic models that are, so far, largely unexplored.

Modeling the Role of Weather and Pilgrimage Variables on Dengue Fever Incidence in Saudi Arabia.

The first case of dengue fever (DF) in Saudi Arabia appeared in 1993 but by 2022, DF incidence was 11 per 100,000 people. Climatologic and population factors, such as the annual Hajj, likely contribute to DF's epidemiology in Saudi Arabia. In this study, we assess the impact of these variables on the DF burden of disease in Saudi Arabia and we attempt to create robust DF predictive models. Using 10 years of DF, weather, and pilgrimage data, we conducted a bivariate analysis investigating the role of weather and pilgrimage variables on DF incidence. We also compared the abilities of three different predictive models. Amongst weather variables, temperature and humidity had the strongest associations with DF incidence, while rainfall showed little to no significant relationship. Pilgrimage variables did not have strong associations with DF incidence. The random forest model had the highest predictive ability (R2 = 0.62) when previous DF data were withheld, and the ARIMA model was the best (R2 = 0.78) when previous DF data were incorporated. We found that a nonlinear machine-learning model incorporating temperature and humidity variables had the best prediction accuracy for DF, regardless of the availability of previous DF data. This finding can inform DF early warning systems and preparedness in Saudi Arabia.

Symmetry in a multi-strain epidemiological model with distributed delay as a general cross-protection period and disease enhancement factor

Symmetry in a multi-strain epidemiological model with distributed delay as a general cross-protection period and disease enhancement factor

Dengue Fever and Global Warming: An Epidemiological Analysis

The article analyzes the connection between the rising number of cases of dengue fever and the warming of the planet’s atmosphere. We underline the significant role that Aedes mosquitoes play in the development of dengue fever by undertaking an in-depth examination of the factors that lead to the disease, how it is transmitted, and how it may be treated. Following that, the study explores the epidemiology of dengue fever and investigates the patterns and trends that the sickness demonstrates in different parts of the globe. We also evaluate the impact that a changing climate has had on the prevalence of dengue fever by relying on data from a wide variety of sources. Preventive measures to battle dengue fever, future patterns in dengue sickness, and the ramifications of those patterns are also discussed.

Prescriptive, descriptive or predictive models: What approach should be taken when empirical data is limited? Reply to comments on "Mathematical models for Dengue fever epidemiology: A 10-year systematic review".

Prescriptive, descriptive or predictive models: What approach should be taken when empirical data is limited? Reply to comments on "Mathematical models for Dengue fever epidemiology: A 10-year systematic review".

Data-rich modeling helps answer increasingly complex questions on variant and disease interactions: Comment on "Mathematical models for dengue fever epidemiology: A 10-year systematic review" by Aguiar et al.

Data-rich modeling helps answer increasingly complex questions on variant and disease interactions: Comment on "Mathematical models for dengue fever epidemiology: A 10-year systematic review" by Aguiar et al.

Concurrent Infection of Dengue and Malaria: An Unusual Case Report

Plasmodium knowlesi is one of the most common causes of Malaria in humans. Although several reported cases of dengue and Malaria occur together, only a few cases have been reported in Southeast Asia, including Indonesia. This study aims to provide additional insight into the epidemiology and clinical aspects of Plasmodium knowlesi (P. knowlesi) malaria infection and dengue fever that occur concurrently in Southeast Asia, particularly Indonesia. A 36-year-old male patient with a history of travel to the mountainous area of Lhoknga and a fever for five days sought treatment at the emergency department of Meuraxa Hospital. During 11 days of treatment, the patient underwent a routine haematology examination every 24 hours. The average platelet count during the first eight days was around 50,000, with an increase after anti-malarial treatment on the eighth day and marked clinical improvement. The patient was discharged on day 10 with no signs of bleeding or hemolysis during treatment. Diagnosis involved blood smears and hematologic examination, confirming dengue fever with P. knowlesi malaria infection. These findings emphasize the importance of thorough history taking, physical examination, and supporting investigations to diagnose these two conditions together. The results of this study may provide critical support for case management involving malaria infection and dengue fever, with a focus on platelet monitoring as an indicator of response to treatment in the Southeast Asian region.

Behavioral and game-theoretic modeling of dengue epidemic: Comment on "Mathematical models for dengue fever epidemiology: A 10-year systematic review" by M. Aguiar et al.

Behavioral and game-theoretic modeling of dengue epidemic: Comment on "Mathematical models for dengue fever epidemiology: A 10-year systematic review" by M. Aguiar et al.

Modeling secondary infections with temporary immunity and disease enhancement factor: Mechanisms for complex dynamics in simple epidemiological models

Modeling secondary infections with temporary immunity and disease enhancement factor: Mechanisms for complex dynamics in simple epidemiological models

Mathematical models for dengue fever epidemiology: A 10-year systematic review.

Mathematical models for dengue fever epidemiology: A 10-year systematic review.

Effect of General Cross-Immunity Protection and Antibody-Dependent Enhancement in Dengue Dynamics

A mathematical model to describe the dynamic of a multiserotype infectious disease at the population level is studied. Applied to dengue fever epidemiology, we analyse a mathematical model with time delay to describe the cross-immunity protection period, including a key parameter for the antibody-dependent enhancement (ADE) effect, the well-known features of dengue fever infection. Numerical experiments are performed to show the stability of the coexistence equilibrium, which is completely determined by the basic reproduction number and by the invasion reproduction number, as well as the bifurcation structures for different scenarios of dengue fever transmission in a population. The model shows a rich dynamical behavior, from fixed points and periodic oscillations up to chaotic behaviour with complex attractors.

A prospective study of prevalence rate epidemiology, risk factors and clinical course of dengue fever in tertiary care hospital

Introduction: The origin of word “dengue” is derived from the ‘Swahili phrase ka-dinga pepo’ which describes the disease is being caused by an evil spirit. The dengue virus, a member of the genus Flavivirus of the family Flaviviridae, is an arthropod –borne virus that includes four different serotypes (DEN-1, DEN-2, DEN-3 and DEN-4). Objectives: To investigate the most affected age groups. To investigate the most affected gender. To evaluate social life (occupation, smoker, alcoholic, diet) of dengue positive patients. To investigate the prevalence /incidence in a particular area/population. To observe intensity and severity of signs and symptoms of various dengue positive effected patients. To evaluate the patient’s concomitant diseases. To investigate further complications which might occur during dengue affected patients. Method: A prospective case series study was done on patients admitted in Maharaja Institute of Medical Sciences, Vizianagaram, AP, India. Results: In our study we included total of 100 patients. Out of 100 patients 54 were females and 46 were males. Number of smokers was 06 and 94 were non smokers out of 100 patients. Alcoholics were 04 and non-alcoholics were 96. Most of the patients were from rural background comprising 70% and remaining 30% who were from urban areas. A symptom of high grade fever was experienced by 68 patients and symptoms of Myalagia by 64%. Most of the patients experienced vomiting/s episode/s. out of 100 patients 55 patients had developed headache. Almost all patients have shown drop in platelet count (thrombocytopenia) as a most potential symptom. 12% of patients had hypertension and 4% of patients had diabetes as co-morbidity. 8% of patients shown re-occurrence of dengue infection.

Climate Variability, Dengue Vector Abundance and Dengue Fever Cases in Dhaka, Bangladesh: A Time-Series Study

Numerous studies on climate change and variability have revealed that these phenomena have noticeable influence on the epidemiology of dengue fever, and such relationships are complex due to the role of the vector—the Aedes mosquitoes. By undertaking a step-by-step approach, the present study examined the effects of climatic factors on vector abundance and subsequent effects on dengue cases of Dhaka city, Bangladesh. Here, we first analyzed the time-series of Stegomyia indices for Aedes mosquitoes in relation to temperature, rainfall and relative humidity for 2002–2013, and then in relation to reported dengue cases in Dhaka. These data were analyzed at three sequential stages using the generalized linear model (GLM) and generalized additive model (GAM). Results revealed strong evidence that an increase in Aedes abundance is associated with the rise in temperature, relative humidity, and rainfall during the monsoon months, that turns into subsequent increases in dengue incidence. Further we found that (i) the mean rainfall and the lag mean rainfall were significantly related to Container Index, and (ii) the Breteau Index was significantly related to the mean relative humidity and mean rainfall. The relationships of dengue cases with Stegomyia indices and with the mean relative humidity, and the lag mean rainfall were highly significant. In examining longitudinal (2001–2013) data, we found significant evidence of time lag between mean rainfall and dengue cases.

Paradigm Shift in Socio-Demographic Profile of Dengue Infection: A Hospital Based Cross-Sectional Study.

Background:Dengue is the most rapidly spreading mosquito borne viral disease in the world with increasing geographical expansion to new countries and from urban to rural settings due to combination of urbanisation, population growth, increased international travel and trade and global warming. The epidemiology of dengue fever in India has been very complex with a seasonal pattern. The first outbreak in Odisha was in 2010 and is now spreading to different districts of the state.Materials and Methods:A hospital based cross-sectional study was carried out between 2017 to 2018 in the dengue ward of a teaching hospital in Berhampur, Ganjam district of Odisha.Results:The prevalence of admitted dengue patients was 4.32%. Majority of the patients were males (81.9%) and ≥15 years old (91.7%). About 68.5% were from rural areas and belonged to low socio-economic status (53.2%). Cases were reported mostly in peri-monsoon periods and 65.7% of them came directly to the hospital.Conclusion:The study highlights the need to curb the rural spread of the disease through activities in creating awareness among all section of people to promote control measures and early reporting of all fever cases, capacity building of rural doctors for early detection, treatment and early referral of high-risk patients and availability of ELISA based tests in sub-district hospitals along with Rapid Diagnostic Kits (RDKs). Emphasis for preventive and control measures to be increased during peri-monsoon periods and also to be instituted in offices, educational institutes and other indoor activity areas.