The Pattern of Adipose Tissue Accumulation during Early Infancy Provides an Environment for the Development of Dengue Hemorrhagic Fever

Role of cytokines produced by T helper immune-modulators in dengue pathogenesis: A systematic review and meta-analysis

BACKGROUND AND OBJECTIVES

Modulation of the immune reaction is essential in the development of various diseases, including dengue's "Cytokine Tsunami", an increase in vascular permeability with concomitant severe vascular leakage. We aim to identify the role of T-helper (Th) cells, Th2 and Th7, with their related cytokines in dengue pathogenesis.

MATERIAL AND METHODS

Nine electronic databases and manual search were applied to detect available publications. A meta-analysis using a fixed- or random-effect model was performed to measure standardized mean difference (SMD) with 95% confidence interval (CI). The National Institute of Health (NIH) tools for observational cohort, cross-sectional, and case-control studies were used to examine the risk of bias. The protocol was recorded in PROSPERO with CRD42017060230.

RESULTS

A total of 38 articles were found including 19 case-control, 11 cross-sectional and 8 prospective cohort studies. We indicated that Th2 cytokines (IL-4, IL-6, IL-8) and Th17 cytokine (IL-17) in dengue patients were notably higher than in a healthy control group in acute phase (SMD = 1.59, 95% CI [0.68, 2.51], p = 0.001; SMD = 1.24, 95% CI [0.41, 2.06], p = 0.003; SMD = 1.13, 95% CI [0.61, 1.66], p<0.0001; SMD = 1.74, 95% CI [0.87, 2.61], p<0.0001), respectively.

CONCLUSIONS

This study provides evidence of the significant roles of IL-4, IL-6, IL-8, IL-10 and IL-17 in the pathogenesis of developing a severe reaction in dengue fever. However, to fully determine the association of Th cytokines with dengue, it is necessary to perform further studies to assess kinetic levels during the duration of the illness.

Viral Febrile Illnesses and Emerging Pathogens

Emerging or emerged diseases and viral pathogens are responsible historically and currently for large epidemics, global pandemics, and significant morbidity and mortality. Our civilization will continue to face the emergence of new pathogens and viruses: viruses will continue to evolve and adapt to new environments at a high rate; our population continues to grow through birth rate, land development, and migration; climate change will continue to increase the vector burden and spread and change the migratory pattern of animals; and our societal mobility will continue to increase through rapid transportation. The clinical evaluation of the febrile patient with a potential emerging viral pathogen involves documenting the likelihood for an infection by a detailed travel history, calculation of an incubation time by exposure, and an understanding of the disease progression though the clinical illness, which drives the differential diagnosis and the type of diagnostics ordered. Ultimately, the proper identification and diagnosis of a patient with a viral febrile illness due to an emerging pathogen will elicit the appropriate precautions to protect health care providers and communities, deliver appropriate therapeutic interventions, and initiate a targeted public health response.

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The majority of emerging diseases are caused by viruses, with many that are transmitted by insect vectors or are zoonotic.

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RNA viruses in particular have high mutation rates and can evolve rapidly in new and changing environments. This, in combination with societal factors, climate change, and rapid travel, has increased the number of epidemics from emerging pathogens in the last several decades.

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Understanding the travel history, incubation time of potential viruses, and the clinical presentation by illness day is essential in making the right diagnosis and identifying the infecting virus.

Trends in dengue research in the Philippines: A systematic review

Dengue is an important public health problem in the Philippines. We sought to describe the trends in dengue research in the country. We searched four databases and identified published studies on dengue research in the Philippines during the past 60 years. We reviewed 135 eligible studies, of which 33% were descriptive epidemiologic studies or case series, 16% were entomologic or vector control studies, 12% were studies on dengue virology and serologic response, 10% were socio-behavioral and economics studies, 8% were clinical trials, 7% were on burden of disease, 7% were investigations on markers of disease severity, 5% were on dengue diagnostics, and 2% were modeling studies. During the last decade, dengue research in the Philippines has increased and evolved from simple descriptive studies to those with more complex and diverse designs. We identified several key topics where more research would be useful.

The association between obesity and dengue virus (DENV) infection in hospitalised patients

Both obesity and DENV infections are growing public health concerns that have far-ranging socioeconomic effects, especially in developing countries. Despite the increasing prevalence of these conditions, there is a scarcity of data investigating the potential relationships between these two entities. Our study aims to examine the influence of obesity on various clinical and laboratory parameters amongst patients with DENV infections. A total of 335 hospitalized patients aged >12 years who were DENV non-structural protein 1 (NS1) antigen-positive were enrolled in this study. Clinical and laboratory variables were compared between patients with and without obesity. Multivariate analysis showed that the following admission clinical findings and laboratory results were independently associated with obesity; chills and rigors (AOR:2.653, 95% CI: 1.286–5.474), higher temperature (AOR:1.485, 95% CI: 1.080–2.042), higher systolic BP (AOR:1.057, 95% CI:1.037–1.078), raised haematocrit (AOR: 1.953, 95% CI: 1.010–3.778), elevated creatinine (AOR:3.504, 95% CI:1.351–9.008) and elevated ALT (AOR: 4.146, 95% CI:1.878–9.154). Obesity was found to be significantly associated with hospitalization >3 days (AOR: 1.990, 95% CI: 1.134–3.494) and the presence of increasing haematocrit with decreasing platelets (AOR: 2.134, 95% CI = 1.235–3.688). Serial assessment of laboratory data revealed that peak haematocrit was significantly higher and nadir platelets levels were significantly lower in obese patients. Both peak and admission levels of leukocyte counts, AST, ALT and creatinine were significantly higher in the obese group. Conversely, both admission and nadir albumin levels were lower for the obese group, although only nadir albumin levels achieved statistical significance. These findings support closer clinical monitoring of obese patients who present with DENV infections, as this patient cohort may possess an increased tendency towards developing more severe clinical manifestations of DENV infections as compared to non-obese patients.