Demographic characteristics, clinical symptoms, biochemical markers and probability of occurrence of severe dengue: A multicenter hospital-based study in Bangladesh.

Establishing reliable early warning models for severe dengue cases is a high priority to facilitate triage in dengue-endemic areas and optimal use of limited resources. However, few studies have identified the complex interactive relationship between potential risk factors and severe dengue. This research aimed to assess the potential risk factors and detect their high-order combinative effects on severe dengue. A structured questionnaire was used to collect detailed dengue outbreak data from eight representative hospitals in Dhaka, Bangladesh, in 2019. Logistic regression and machine learning models were used to examine the complex effects of demographic characteristics, clinical symptoms, and biochemical markers on severe dengue. A total of 1,090 dengue cases (158 severe and 932 non-severe) were included in this study. Dyspnoea (Odds Ratio [OR] = 2.87, 95% Confidence Interval [CI]: 1.72 to 4.77), plasma leakage (OR = 3.61, 95% CI: 2.12 to 6.15), and hemorrhage (OR = 2.33, 95% CI: 1.46 to 3.73) were positively and significantly associated with the occurrence of severe dengue. Classification and regression tree models showed that the probability of occurrence of severe dengue cases ranged from 7% (age >12.5 years without plasma leakage) to 92.9% (age ≤12.5 years with dyspnoea and plasma leakage). The random forest model indicated that age was the most important factor in predicting severe dengue, followed by education, plasma leakage, platelet, and dyspnoea. The research provides new evidence to identify key risk factors contributing to severe dengue cases, which could be beneficial to clinical doctors to identify and predict the severity of dengue early.

Serum levels of matrix metalloproteinases as prognostic markers for severe dengue with plasma leakage.

BACKGROUND: Plasma leakage is a major pathogenic manifestation of severe dengue and is a precursor of life-threatening complications associated with dengue. Accumulating evidence indicates the role of Matrix Metalloproteinases (MMPs) in mediating vascular permeability and plasma leakage following induction by the dengue virus. This study aims to investigate the utility of MMP-2, MMP-3, and MMP-9 in predicting the severity of dengue infection and further explore the relationship of these markers with the pathogenic factors associated with plasma leakage. METHODS: The dengue-positive subjects were classified into mild and severe dengue groups based on the manifestation of warning signs. The samples in each group and healthy controls were quantified for basic laboratory characteristics. The levels of MMP-2, MMP-3, MMP-9, and Macrophage migration inhibitory factor (MIF) were estimated in all serum samples using a multiplex bead-based assay. RESULTS: MMP-2 and MMP-9 were markedly elevated in severe dengue patients compared to mild dengue patients and healthy controls. No alteration in the circulating levels of MMP-3 was observed between the study groups. ROC curve analysis indicated that MMP-2 and MMP-9 exhibited good potential for predicting severe dengue. Notably, an increase in MMP-9 was associated with increased MIF and Hematocrit levels in severe dengue patients. CONCLUSION: MMP-2 and MMP-9 could serve as prognostic biomarkers for severe dengue. These findings also identify the association of MMP-9 with markers of plasma leakage, thereby encouraging further studies to explore the therapeutic potential of targeting MMP-9 in managing plasma leakage in severe dengue.

The fewer, the better fare: Can the loss of vegetation in the Cerrado drive the increase in dengue fever cases infection?

Several studies have reported the relationship of deforestation with increased incidence of infectious diseases, mainly due to the deregulation caused in these environments. The purpose of this study was to answer the following questions: a) is increased loss of vegetation related to dengue cases in the Brazilian Cerrado? b) how do different regions of the tropical savanna biome present distinct patterns for total dengue cases and vegetation loss? c) what is the projection of a future scenario of deforestation and an increased number of dengue cases in 2030? Thus, this study aimed to assess the relationship between loss of native vegetation in the Cerrado and dengue infection. In this paper, we quantify the entire deforested area and dengue infection cases from 2001 to 2019. For data analyses, we used Poisson generalized linear model, descriptive statistics, cluster analysis, non-parametric statistics, and autoregressive integrated moving average (ARIMA) models to predict loss of vegetation and fever dengue cases for the next decade. Cluster analysis revealed the formation of four clusters among the states. Our results showed significant increases in loss of native vegetation in all states, with the exception of Piauí. As for dengue cases, there were increases in the states of Minas Gerais, São Paulo, and Mato Grosso. Based on projections for 2030, Minas Gerais will register about 4,000 dengue cases per 100,000 inhabitants, São Paulo 750 dengue cases per 100,000 inhabitants, and Mato Grosso 500 dengue cases per 100,000 inhabitants. To reduce these projections, Brazil will need to control deforestation and implement public health, environmental and social policies, requiring a joint effort from all spheres of society.

Different domains of dengue research in the Philippines: A systematic review and meta-analysis of questionnaire-based studies.

BACKGROUND: Dengue is the most rapidly spreading mosquito-borne viral disease of humans worldwide, including southeast Asia region. This review provides a comprehensive overview of questionnaire-related dengue studies conducted in the Philippines and evaluates their reliability and validity in these surveys. METHODS: A review protocol constructed by a panel of experienced academic reviewers was used to formulate the methodology, research design, search strategy and selection criteria. An extensive literature search was conducted between March-June 2020 in various major electronic biomedical databases including PubMed, EMBASE, MEDLINE and ScienceDirect. A systematic review and meta-analysis (PRISMA) were selected as the preferred item reporting method. RESULTS: Out of a total of 34 peer-reviewed dengue-related KAP studies that were identified, 15 published from 2000 to April 2020 met the inclusion criteria. Based on the meta-analysis, a poor mean score was obtained for each of knowledge (68.89), attitude (49.86) and preventive practice (64.69). Most respondents were equipped with a good knowledge of the major clinical signs of dengue. Worryingly, 95% of respondents showed several negative attitudes towards dengue prevention, claiming that this was not possible and that enacting preventive practices was not their responsibility. Interestingly, television or radio was claimed as the main source of gaining dengue information (range 50-95%). Lastly, only five articles (33.3%) piloted or pretested their questionnaire before surveying, of which three reported Cronbach's alpha coefficient (range 0.70 to 0.90). CONCLUSION: This review indicates that to combat the growing public health threat of dengue to the Philippines, we need the active participation of resident communities, full engagement of healthcare personnel, promotion of awareness campaigns, and access to safe complementary and alternative medicines. Importantly, the psychometric properties of each questionnaire should be assessed rigorously.

The emergence of Dengue Fever in Sheikhupura, Pakistan: its seroprevalence and risk factors assessment during 2014-2017.

INTRODUCTION: District Sheikhupura encountered its first dengue outbreak in 2014 but lacked serological evidence and reports of risk factors associated with it. To assess this, a hospital-based study was conducted from January 2014 to December 2017. METHODOLOGY: Blood from 333 participants was collected, the serum obtained was tested for IgG and IgM antibodies against DENV using a commercially available ELISA kit. RESULTS: The results showed that out of all (n= 333) samples tested, 120 were turned up positive for DENV, making an overall prevalence of 36%. Of the 120 confirmed cases, 55% (n = 66) were recorded in 2014, 10% (n = 12) in 2015, 27.5% (n = 33) in 2016, and 7.5% (n = 9) in 2017. It was found that 68.3% (n = 82) were male and 31.7% (n = 38) were female, with 61% (n = 74) patients aged between 11-30 years. The highest prevalence of infection, 94.2% (n = 113), was noted after the rainy season. During the study, the highest number of cases appeared in Ferozewala Tehsil. The factors age, gender, and season were found statistically significant with the prevalence of infection (p < 0.05). CONCLUSIONS: The study is the first report on the detection of dengue in the Sheikhupura district. The survey anticipated its geographical expansion, determined associated risk factors, and suggests active disease surveillance in the area.

Longitudinal Analysis of Dengue Virus-Specific Memory T Cell Responses and Their Association With Clinical Outcome in Subsequent DENV Infection.

Memory T cells resulting from primary dengue virus (DENV) infection are hypothesized to influence the clinical outcome of subsequent DENV infection. However, the few studies involving prospectively collected blood samples have found weak and inconsistent associations with outcome and variable temporal trends in DENV-specific memory T cell responses between subjects. This study used both ex-vivo and cultured ELISPOT assays to further evaluate the associations between DENV serotype-cross-reactive memory T cells and severity of secondary infection. Using ex-vivo ELISPOT assays, frequencies of memory T cells secreting IFN-γ in response to DENV structural and non-structural peptide pools were low in PBMC from multiple time points prior to symptomatic secondary DENV infection and showed a variable response to infection. There were no differences in responses between subjects who were not hospitalized (NH, n=6) and those who were hospitalized with dengue hemorrhagic fever (hDHF, n=4). In contrast, responses in cultured ELISPOT assays were more reliably detectable prior to secondary infection and showed more consistent increases after infection. Responses in cultured ELISPOT assays were higher in individuals with hDHF (n=8) compared to NH (n=9) individuals before the secondary infection, with no difference between these groups after infection. These data demonstrate an association of pre-existing DENV-specific memory responses with the severity of illness in subsequent DENV infection, and suggest that frequencies of DENV-reactive T cells measured after short-term culture may be of particular importance for assessing the risk for more severe dengue disease.

Dengue virus induces interferon-ß by activating RNA sensing pathways in megakaryocytes.

Activation of innate receptors in megakaryocytes (MKs) may affect the ability to produce functional platelets. Low platelet count is one of the clinical manifestations of dengue virus (DENV) infection. In MKs, the effect of innate receptors during DENV-infection is not well studied. Here we used MEG-01 cells to investigate DENV serotype 2 induced innate receptors in these cells. DENV RNA was estimated by qRT-PCR in the culture supernatant. The expression of innate receptors was determined by western blot and qPCR. DENV infection led to increased expression of RIG-I at 24 hrs post-infection (hpi) and MDA-5 at 48 and 72 hpi (p<0.05). However, no change in the expression of TLR3 at protein level was observed. Activation of MDA-5 resulted in increased expression of IFN-ß and ISG-15 in DENV infected MEG-01 cells, which was further confirmed by MDA-5 siRNA treatment. Apart from inducing innate receptors, DENV significantly decreases the expression of CD61, an activation marker of megakaryocyteson MEG-01 cells as observed by flow cytometry analysis (p<0.01). Results from this study confirm that DENV infection activates the type-I interferon in megakaryocytes and may play a significant role in maturation and development.

Case Report: Transmission of Dengue Virus from a Deceased Donor to a Kidney Transplant Recipient Previously Infected by Dengue Virus.

Since 2018, a dengue epidemic has been ongoing in the French overseas department of Reunion Island, in the Indian Ocean, with more than 25,000 serologically confirmed cases. Currently, three dengue serotypes have been identified in Réunion Island (DENV-1, DENV-2, and DENV-3) progressing in the form of epidemic outbreaks. This arbovirus is mainly transmitted by mosquitoes of the genus Aedes and may be responsible for serious clinical forms. To date, very few cases of kidney transplant-related dengue virus infection have been described. Here we report the first case of severe dengue virus infection related to kidney transplantation from a patient previously infected with dengue. Testing for dengue fever with PCR search in donor's urine may help complete the pretransplant assessment in areas where this disease occurs.

Exploring the utility of social-ecological and entomological risk factors for dengue infection as surveillance indicators in the dengue hyper-endemic city of Machala, Ecuador.

The management of mosquito-borne diseases is a challenge in southern coastal Ecuador, where dengue is hyper-endemic and co-circulates with other arboviral diseases. Prior work in the region has explored social-ecological factors, dengue case data, and entomological indices. In this study, we bring together entomological and epidemiological data to describe links between social-ecological factors associated with risk of dengue transmission at the household level in Machala, Ecuador. Households surveys were conducted from 2014-2017 to assess the presence of adult Aedes aegypti (collected via aspiration) and to enumerate housing conditions, demographics, and mosquito prevention behaviors. Household-level dengue infection status was determined by laboratory diagnostics in 2014-2015. Bivariate analyses and multivariate logistic regression models were used to identify social-ecological variables associated with household presence of female Ae. aegypti and household dengue infection status, respectively. Aedes aegypti presence was associated with interruptions in water service and weekly trash collection, and household air conditioning was protective against mosquito presence. Presence of female Ae. aegypti was not associated with household dengue infections. We identified shaded patios and head of household employment status as risk factors for household-level dengue infection, while window screening in good condition was identified as protective against dengue infection. These findings add to our understanding of the systems of mosquito-borne disease transmission in Machala, and in the larger region of southern Ecuador, aiding in the development of improved vector surveillance efforts, and targeted interventions.

Manifestaciones cardiovasculares en pacientes hospitalizados con dengue / Cardiovascular disorders in hospitalized patients with dengue infection

Introducción: Las complicaciones cardiacas en pacientes con dengue no son infrecuentes y no son diagnosticadas, ya que usualmente son leves y autolimitadas. Objetivos: Caracterizar las manifestaciones cardiovasculares en pacientes hospitalizados con infección por dengue. Métodos: Se realizó un estudio epidemiológico observacional, analítico, de corte longitudinal, prospectivo, que incluyó 427 pacientes atendidos en el Hospital Docente Clínico-Quirúrgico Comandante Manuel Fajardo con diagnóstico de infección por dengue durante el periodo comprendido desde abril de 2017 hasta abril de 2018. Resultados: Las manifestaciones cardiovasculares (19,7%), principalmente los trastornos del ritmo (bradicardia sinusal [13,8%], extrasístoles auriculares [4,9%] y ventriculares [4,0%]) fueron frecuentes en pacientes con infección por dengue. La pericarditis y miocarditis se identificó en el 1,6% y 0,2%, respectivamente. Estas manifestaciones fueron autolimitadas en el 83,3% y se presentaron en los primeros días de inicio del cuadro febril en el 75,0%. La edad avanzada (OR=1,70), el sexo masculino (OR=1,94), el recuento de plaquetas disminuido (OR=1,13) y el dengue con signos de alarma (OR=3,29) se relacionaron con una mayor probabilidad de presentar manifestaciones cardiovasculares en el curso de una infección por dengue. Conclusiones: Las manifestaciones cardiovasculares en pacientes con dengue son frecuentes, y se relacionan con la edad avanzada, el sexo masculino, así como las formas severas de la enfermedad.(AU)

Introduction: Cardiac complications in dengue patients are not uncommon and are not diagnosed, since they are usually mild and self-limiting. Objectives: To characterize the cardiovascular manifestations in hospitalized patients with dengue infection. Methods: We conducted an observational, analytical, longitudinal, prospective epidemiological study, which included 427 patients treated at Manuel Fajardo Clinical-Surgical Teaching Hospital with diagnosis of dengue infection since April 2017 to April 2018. Results: Cardiovascular manifestations (19.7%), mainly heart rate disorders (sinus bradycardia [13.8%], atrial [4.9%] and ventricular [4.0%] extrasystoles) were frequent in dengue infection patients. Pericarditis and myocarditis were diagnosed in 1.6% and 0.2% respectively. These disorders were self-limiting in 83.3% of cases and occurred in the first days of the onset of fever in 75.0%. Advanced age (OR=1.70), male sex (OR=1.94), decreased platelet count (OR=1.13) and dengue with warning signs (OR=3.29) were related to a higher probability of presenting cardiovascular disorders in the course of a dengue infection. Conclusions: Cardiovascular manifestations in dengue patients are frequent, and are related to advanced age, male sex, as well as severe forms of the disease.(AU)

The Impact of Sociological and Environmental Factors for Dengue Infection in Kuala Lumpur, Malaysia.

BACKGROUND: Dengue incidence has grown dramatically around the world in recent years. Vector control is the only method to reduce dengue incidence due to the lack of a vaccine available. By understanding the factors contributed to the vector densities such as environmental and sociological factors, dengue prevention and control may succeed. OBJECTIVE: This study is aimed at determining the impact of sociological and environmental factors contributing to dengue cases. METHODS: The study surveyed 379 respondents with dengue history. The socio-environmental factors were evaluated by chi-square and binary regression. RESULT: The chi-square results revealed sociological factors associated between family with dengue experience such as older age (p =0.012), fewer than four people in the household (p= 0.008), working people (p= 0.004) and apartment/terrace houses (p=0.023). Similarly, there is a significant association between respondent's dengue history and houses that are shaded with vegetation (p= 0.012) and the present of public playground areas near the residential (p = 0.011). CONCLUSION: The study identified socio-environmental factors that play an important role in the abundance of Aedes mosquitoes and also for the local dengue control measures.

A Bayesian Functional Methodology for Dengue Risk Mapping in Latin America and the Caribbean.

Dengue fever has become one of the most outstanding infectious diseases in the world. Besides, the incidence and prevalence of dengue are increasing in the endemic areas of the tropical and subtropical regions. Space and time disease mapping models are common instruments to explain the patterns of disease counts, where hierarchical Bayesian models constitute a suitable framework for their formulation. These random events reflect interactions between nearby geographic locations, as well as correlations between close temporary instants. Functional data analysis techniques can better describe the evolution of disease mapping. In this paper, the risk of dengue in Mexico, Central and South America is studied from a Functional approach through a Bayesian estimation model focused on Hilbert-valued autoregressive processes combined with the Kalman filtering algorithm. Thus, the temporal functional evolution of spatial geographic patterns of incidence risk in disease mapping during 1998-2018 is approximated. Applying this methodology, the excess of smoothing that occurs with traditional models is avoided and the heterogeneity is conserved across the years. It improves the number of false positives created by noise and the number of false negatives as well. The results obtained with the application of this model are compared with those of previous models, corroborating the preceding statements and obtaining better results in the relative risk estimates, providing greater robustness and stability of disease risk estimates.

Epidemiological and clinical analysis of the outbreak of dengue fever in Zhangshu City, Jiangxi Province, in 2019.

This study analyzed the epidemiological and clinical features of dengue fever in Zhangshu, Jiangxi Province, in 2019 and provided evidence for the diagnosis, treatment, prevention, and control of dengue fever. A total of 718 dengue fever patients in Zhangshu in 2019 were involved. ELISA and qRT-PCR were used for pathogenic detection of dengue virus. Multiple adjuvant therapies were applied, and the condition of patients after treatment was examined. Patients were between the ages of 0.75 and 92 years old, and all of them had a fever. A total of 519 cases had fatigue, and 413 cases had generalized myalgia and bone ache; 356 cases had dry mouth, 289 cases had bitter taste, and 167 cases felt dry and bitter taste; 279 cases had rash, and 93 cases had pruritus; 587 cases had decreased leukocyte, among which, 7 cases had leukocyte lower than 1 × 10 [9]/L; 380 cases had a low platelet count, and the platelet count of 29 cases was lower than 50 × 10 [9]/L; 488 cases had increased aspartic transaminase, and 460 cases had increased alanine aminotransferase; 5 cases had a severe disease. It proved that the majority of dengue fever sufferers were adults, with the main clinical features being fever and rash and the chief injured organs being the blood system, liver, heart, and gastrointestinal tract. Besides, over 40% of patients had dry and bitter taste, and 12 cases had alopecia after discharge. It indicates that the incidence of dengue fever in Zhangshu is closely related to the sudden population flow and imported cases.

Characterization of the IL-17 and CD4+ Th17 Cells in the Clinical Course of Dengue Virus Infections.

The aims of this study were to determine the involvement of interleukin 17 (IL-17) and IL-17-producing cells in dengue pathogenesis. Blood samples from dengue virus (DENV)-infected patients were collected on different days after the onset of symptoms. Patients were classified according to 1997 World Health Organization guidelines. Our study examined 152 blood samples from dengue fever (DF, n = 109) and dengue hemorrhagic fever (DHF, n = 43) patients and 90 blood samples from healthy controls (HC). High serum concentrations of IL-17A and IL-22 were also associated with DHF (IL-17A [DHF vs. DF, p < 0.01; DHF vs. HC, p < 0.0001]; IL-22 [DHF vs. DF, p < 0.05; DHF vs. HC, p < 0.0001]). Moreover, there was a positive correlation between serum levels of IL-17A and IL-23, a key cytokine that promotes IL-17-based immune responses (r = 0.4089, p < 0.0001). Consistent with the IL-17-biased immune response in DHF patients, we performed ex vivo activation of peripheral blood mononuclear cells (PBMCs) from DHF patients and flow cytometry analysis showed a robust IL-17-biased immune response, characterized by a high frequency of CD4+IL-17+ producing cells. Our results suggests IL-17-producing cells and their related cytokines can play a prominent role in this viral disease.

Spatiotemporal modeling of dengue fever risk in Puerto Rico.

Dengue Fever (DF) is a mosquito vector transmitted flavivirus and a reemerging global public health threat. Although several studies have addressed the relation between climatic and environmental factors and the epidemiology of DF, or looked at purely spatial or time series analysis, this article presents a joint spatio-temporal epidemiological analysis. Our approach accounts for both temporal and spatial autocorrelation in DF incidence and the effect of temperatures and precipitation by using a hierarchical Bayesian approach. We fitted several space-time areal models to predict relative risk at the municipality level and for each month from 1990 to 2014. Model selection was performed according to several criteria: the preferred models detected significant effects for temperature at time lags of up to four months and for precipitation up to three months. A boundary detection analysis is incorporated in the modeling approach, and it was successful in detecting municipalities with historically anomalous risk.

Large-scale multivariate forecasting models for Dengue - LSTM versus random forest regression.

Effective management of seasonal diseases such as dengue fever depends on timely deployment of control measures prior to the high transmission season. As the epidemic season fluctuates from year to year, the availability of accurate forecasts of incidence can be decisive in attaining control of such diseases. Obtaining such forecasts from classical time series models has proven a difficult task. Here we propose and compare machine learning models incorporating feature selection,such as LASSO and Random Forest regression with LSTM a deep recurrent neural network, to forecast weekly dengue incidence in 790 cities in Brazil. We use multivariate time-series as predictors and also utilize time series from similar cities to capture the spatial component of disease transmission. The LSTM recurrent neural network model attained the highest performance in predicting future incidence on dengue in cities of different sizes.

Case report: Mononeuritis multiplex in the course of dengue fever.

BACKGROUND: Dengue fever usually presents as a self-limiting acute febrile illness with worsening thrombocytopenia, with a small minority of patients developing hemorrhagic or life-threatening complications. Organ specific manifestations like myocarditis, acalculous cholecystitis, encephalitis has been described but are uncommon presentations. Even more rarely, such manifestations are the presenting complaint of Dengue fever. In this case report, we highlight a case of Dengue fever where unrelated neuropathies were the presenting complaint. CASE PRESENTATION: An elderly man presents with 1 day of diplopia and left foot drop, associated with 2 days history of fever. A decreasing white cell count (WBC) and platelet on the 2nd day of admission prompted Dengue virus to be tested and a positive NS-1 antigen was detected, confirming the diagnosis of Dengue fever. He was treated with supportive treatment with a short duration of intravenous fluids recovered uneventfully and was discharged 6 days after admission with almost full resolution of diplopia and partial resolution of left foot drop. Left foot drop recovered completely 2 weeks later. CONCLUSION: Neurological manifestations can be the presenting symptoms in Dengue fever, a diagnosis which should be borne in mind when such symptoms present in patients from endemic areas or in returning travellers from these areas.

DZC DIAG: mobile application based on expert system to aid in the diagnosis of dengue, Zika, and chikungunya.

Dengue, Zika, and chikungunya are epidemic diseases transmitted by the Aedes mosquito. These virus infections can be so severe to the point of bringing on mobility and neurological problems, or even death. Expert systems (ES) can be used as tools for the identification of patterns intended to solve problems in the same way as a professional specialist would. This work aimed to develop an ES in the form of an Android application to serve as a supportive tool in the diagnosis of these arboviruses. The goal is to associate the set of symptoms from a patient to a score related to the likelihood of them having these diseases. To make this possible, we implemented a rule-based ES which considers the presence of symptoms itself and the relation between them to associate the case under analysis to others found in the literature. We performed 96 tests (32 for each illness), and our system had a success rate of 96.88%. Resident physicians of a public hospital also analyzed these clinical cases and achieved an average success rate of 72.92%. Comparing the results of the method proposed and errors made by health professionals, we showed an improvement in the effectiveness of clinical diagnoses. Graphical abstract Figure - DZC DIAG Operating Flowchart: the physicians record patients' data and answer a series of questions related to the patient's symptoms; after all the questions, the result is generated by the expert system (score for dengue, Zika, and chikungunya); and it is saved in the same device where the test was done and uploaded online to a FTP.

Vaso-occlusive crisis in a sickle cell patient after transfusion-transmitted dengue infection.

CASE REPORT: A 26-year-old woman with sickle cell disease (SCD) on chronic transfusion therapy complained of severe arthralgia, myalgia, abdominal pain, headache, and fever 24 hours after transfusion of a red blood cells (RBCs). Dengue virus (DENV) infection was suspected and the patient was hospitalized for clinical support and RBC transfusion, to lower the hemoglobin S to less than 30%. The patient's clinical condition improved approximately 8 days after the onset of symptoms. RESULTS: DENV type 2 (DENV-2) TaqMan real-time polymerase chain reaction was negative in the patient's pretransfusion sample while the posttransfusion sample was positive (Ct, 27.8), suggesting a high viral load and an acute infection. To investigate DENV transfusion transmission (TT-DENV) the stored donor serum was tested and was also positive (Ct, 25.8). Molecular typing confirmed the presence of DENV-2. The phylogenetic analysis of the DENV-2 strains obtained from both donor and patient samples were classified as the Southeast Asia-American genotype (Genotype III) and demonstrated 100% genomic identity, indicating TT-DENV. CONCLUSION: This is the first description of TT-DENV in a SCD patient. A presumed high viral load in the transfused RBC unit probably determined the early clinical manifestation. In endemic regions dengue fever should be considered as differential diagnosis in SCD patients with fever and acute pain crisis, mainly during DENV outbreaks.