Journal of Vector Borne Diseases最新文献

Background objectives: Dengue virus, a mosquito-borne flavivirus, is a serious worldwide health risk that can be fatal. Its replication is dependent on the NS2B/NS3 protease. Given the critical need for effective antivirals and the documented medicinal properties of Nigella sativa bioactive compounds, this study used molecular docking and ADMET analysis to assess the potential of N. sativa bioactive compounds as NS2B/NS3 protease inhibitors.

Methods: A total of 151 bioactive compounds from N. sativa were retrieved from the PubChem database. Molecular docking analyses were carried out using AutoDock Vina in conjunction with PyRx (v. 0.8) virtual screening tools. Physiochemical and ADMET properties of the top four compounds were evaluated using SwissADME and Deep-PK tools.

Results: The screening resulted 19 compounds with higher binding affinity values than the control compound Lopinavir. This study focused on the top four compounds (PubChem IDs: 11277543, 118717506, 101257318, and 102575929) that were found to form multiple hydrogen bonds and hydrophobic interactions with the NS2B/NS3 protease active site. Importantly, these compounds interacted with the catalytic triad of His51, Asp75, and Ser135 residues of NS2B/NS3 protease. Furthermore, these compounds had favourable druglikeness, pharmacokinetic, and toxicity profiles.

Interpretation conclusion: The compounds (PubChem IDs: 11277543, 118717506, 101257318, and 102575929) can be used as potential NS2B/NS3 protease inhibitors for further experimental validation and development in dengue management.

Background objectives: Molecular tests play crucial role in diagnosis, however, acquiring appropriate controls is challenging owing to strict biosafety and biosecurity regulations. Herein, we suggest an alternative to live virus for inclusion as positive controls in molecular testing.

Methods: We used inactivated antigens provided with ELISA kits, both as they are and after spiking the vector samples. The extracted RNA/DNA was used as a positive control in RT- PCR/PCR reactions.

Results: The PCR product of expected size and sequencing results confirmed that the inactivated antigens can be used as positive controls for Dengue, Chikungunya, Japanese Encephalitis and Lymphatic Filariasis in molecular tests.

Interpretation conclusion: We demonstrate that the inactivated antigens supplied with ELISA kits or obtained from microscopic slide can be used as positive controls in molecular tests while testing human and vector samples. This will be a useful technique for laboratories in resource constrained settings or during emergency situations.

Background objectives: Dengue represents a high economic and health burden, particularly in low, and middle-income countries, as in Brazil. This study aimed to evaluate the impact of demographic, clinical and laboratory characteristics on dengue-related hospital stay in Bauru, Brazil.

Methods: This was a retrospective, cross-sectional, observational study that evaluated the impact of demographic characteristics (age, sex, and self-reported ethnicity), of chronic diseases (diabetes mellitus, systemic arterial hypertension, chronic kidney disease, dyslipidemia, cancer, cardiomyopathy, and heart failure), clinical signs (hematemesis, hepatomegaly, and edema), and symptoms (anemia), alone or in combination, in the length of hospitalization. All patients admitted for dengue in a public tertiary-level referral hospital in Bauru, São Paulo, Brazil, 2019, were included. A survival analysis was performed for statistical purposes.

Results: Overall, 234 patients were evaluated, whose mean age was 35.35±1.80 years with an average length of hospitalization of 6.38±0.44 days. The final model presented higher ages, the presence of chronic diseases and clinical alterations as significant variables in determining the length of hospitalization.

Interpretation conclusion: Patients with dengue presented long hospitalization lengths at discharge, mainly those with higher ages, chronic diseases (diabetes mellitus, systemic arterial hypertension, chronic kidney disease, heart failure) and clinical signs (edema) and symptoms (anemia) alone or in combination. Sex, self-reported ethnicity, cancer, cardiomyopathy, dyslipidemia, hematemesis, and hepatomegaly had no significant impact on the length of hospitalization. Prevention of the disease through continuous education and immunization of the general population, mainly those belonging to high-risk groups, is urgently needed.

This review explores the structural dynamics of Dengue virus (DENV) during human-to-human transmission mediated by mosquito vectors, primarily Aedes aegypti. DENV remains a global health concern, with increasing cases due to climate change, urbanization, and mosquito adaptation. The structural biology of DENV, including its envelope (E), membrane (M), capsid (C) proteins, and RNA genome, plays a critical role in transmission and infectivity. The transmission cycle begins when mosquitoes ingest the virus from an infected human and later transmit it to others after viral replication within their salivary glands. Structural adaptations occur both in the mosquito host and human cells, enhancing viral stability and infectivity. Host-virus interactions, such as immune evasion and cellular entry mechanisms, further complicate disease progression. This review highlights the impact of structural changes on viral replication, pathogenesis, and resistance, while emphasizing recent research advancements and future challenges. Understanding these molecular mechanisms is crucial for developing effective therapeutics and controlling DENV spread.

Background objectives: This study aimed to assess chest computed tomography (CT) scans and laboratory parameters of patients with Crimean-Congo hemorrhagic fever (CCHF) and compare results between survivors and non-survivors.

Methods: Patients diagnosed with CCHF between July 2012 and July 2021 were examined retrospectively. Patient data, thorax CT findings, laboratory results, and demographic characteristics were evaluated. Survivors and non-survivors were compared for ground-glass opacity (GGO), pleural effusion, atelectasis, lung consolidation, pulmonary nodules, bronchiectasis, pericardial effusion, and enlarged mediastinal lymph nodes. Laboratory findings and respiratory complaints were recorded regarding survival status.

Results: A total of 112 patients were included, with a mean age of 54.2 years and 56.3% male predominance. The most common CT findings were GGO (46.3%), pleural effusion (40%), and atelectasis (36.3%). GGO, pleural effusion, atelectasis, lung consolidation, and pericardial effusion were more frequent in non-survivors than survivors (p<0.05).Non-survivors demonstrated significantly altered laboratory parameters including elevated WBC counts (p<0.01), reduced platelet counts (p<0.001), decreased fibrinogen (p<0.01), and prolonged coagulation times (PT and aPTT, both p<0.001). Pleural effusion and GGO showed significantly higher mortality risk (11.23-fold and 5.89-fold adjusted, respectively).

Interpretation conclusion: GGO, lung consolidation, pleural effusion, pericardial effusion, and atelectasis may serve as poor prognostic indicators, necessitating close monitoring for patients with these potentially life-threatening findings.

Background objectives: Bandung City, West Java, Indonesia, is one of the hyperendemic areas for dengue virus (DENV) infections. However, data on virus distribution in this area is currently limited. This study aims to assess the distribution of serotypes and genotypes of DENV isolated from dengue patients in primary healthcare facilities (PHC) in 2018.

Methods: A cross-sectional study was conducted in three PHCs in Bandung City from May to October 2018. Suspected dengue patients with a fever lasting than five days were enrolled. Demographic and clinical data were collected upon enrollment. Dengue NS1 rapid diagnostic test (RDT) were followed by RT-PCR and nested PCR performed on patients' serum samples. A phylogenetic tree was constructed based on E-gene sequence data.

Results: A total of 236 suspected dengue patients were enrolled in this study, with 51 confirmed dengue infections based on the NS1 rapid test. Among these 51 cases, 23 (45%) were positive by RT-PCR (2 DENV-1, 6 DENV-2, 10 DENV-3, 3 DENV-4, and 2 with mixed DENV serotypes). The predominance DENV-3 in 2018 was consistent with the reports from 2008, indicating the same predominant serotype circulated in the area. Phylogenetic analysis revealed that DENV-1 genotype 1 and DENV-3 genotype 1 were circulating in Bandung.

Interpretation conclusion: All four DENV serotypes were identified in samples collected from PHC Neglasari, Padasuka, and Sukajadi, confirming that Bandung is a hyperendemic areas. Strengthening vector control measures is crucial to prevent further transmission of dengue infection.

Backgound objectives: A small-scale In2Care® EaveTubes (ET) new malaria vector control product efficacy study was carried out at Kagera Sugar Ltd, Missenyi, Tanzania between October 2019 and July 2020. Its main aim was to gather proof of impact against wild populations of anopheline mosquitoes (malaria vectors) in Tanzanian rural field settings.

Methods: In total, 350 Eave Tubes were installed in 100 iron sheet barrack rooms and 35 mud houses in a selected camp where workers of Kagera Sugar Ltd resided. Two similar camps did not receive any malaria interventions and served as control sites to monitor baseline mosquito densities. During the 9-month intervention period, the quality and durability of the insecticide- treated ET were tested. Entomological sampling was conducted to assess indoor mosquito densities pre- and post ET installation. Furthermore, malaria disease cases were monitored through passive case detection at the local health facility to indicate potential epidemiological impacts.

Results: Entomological data showed that ET significantly reduced indoor anopheline vector densities by 58% overall and 75% during the peak mosquito season. Quality control results showed no degradation of insecticide content or mosquitocidal efficacy of ET netting samples used for 6 months under field conditions. Malaria incidence results showed a decline in disease cases in the ET-treated camp and the control camps, compared to the baseline. The highest malaria case incidence reduction was in the ET intervention camp (25.6%).

Interpretation conclusion: These findings indicate a high efficacy and durability of ET against wild malaria mosquitoes. Eave Tubes can be a new tool in the malaria control toolbox, complementing malaria vector control tools available in areas where insecticide resistance has compromised existing vector control tools.

Background objectives: The proportion of asymptomatic malaria is no doubt one of the factors determining the dynamics of its transmission and burden in endemic areas. This research focused on screening for Plasmodium parasitemia and analysing the relationship between proportions of malaria cases among asymptomatic and symptomatic persons in Lokoja, Northcentral Nigeria.

Methods: Cross-sectional survey and experimental designs were adopted. A semi-structured interview guide was used to collect data on socio-demography and clinical status of the participants. Blood samples were randomly collected from 328 consenting participants during high transmission season (April - October) of malaria within a three-year period (2018-2021), and screened for Plasmodium species by light microscopy (LM). Statistical analyses of related parameters were performed using the Statistical Package for the Social Sciences (SPSS) version 25 software.

Results: A total of 12.4% (25/202) and 85.7% (108/126) asymptomatic and symptomatic individuals were recorded respectively. There was no significant difference (p > 0.05) between the mean distributions of malaria cases among the asymptomatic and those of symptomatic persons. All cases identified were uncomplicated and falciparum-specific; and a 40.5% (133/328) prevalence of P. falciparum malaria with hyperparasitemia was observed in the area. The implications of these findings were discussed in relation to previous rates and other nearby endemic settings.

Interpretation conclusion: As a matter of success towards malaria elimination, a renewed call is made for regular monitoring of malaria prevalence using more efficient means of diagnosis and consideration of control strategies such as regular mass antimalarial administration, particularly targeting the often-neglected asymptomatic reservoir subset.

Background objectives: Chagas is a neglected tropical disease with a significant socioeconomic impact. Although several studies have focused on evaluating its epidemiological aspects, the cyclical behavior of its incidence and mortality remains poorly explored; thereto, this study aimed to evaluate them.

Methods: This was a retrospective with populational approach study that employed data from the Global Burden of Disease. The cyclicity was evaluated by using the Fast Fourier Transform to fit cyclical sinusoidal models for every period between 2 and 40 years in 0.1 -year increments. Each model was manually evaluated by its p-value of joint sine-cosine term, its semiamplitude, its 95% confidence interval, and how well it followed the graphical behavior of the reference source. Data were stratified by age group, sex, and country by using R software 4.4.2.

Results: Overall, cycles betwixt 20 and 30 years were identified, with incidence and mortality cyclicity displaying alignment trends. Shorter cycle lengths were observed in the 0-14 age group compared to other age groups. Sex differences were minor noted. Between the evaluated countries, Mexico and Argentina presented shorter mortality cycles in comparison with their incidence cycles.

Interpretation conclusion: Interpretation & Conclusion: Although there are some specificities in the Chagas cyclicity, there is a general tendency of alignment among its cycles. Recognizing these patterns, derived from a complex interplay between biological, economic, social, and political variables, is fundamental to optimizing the timing and targeting of public health interventions on the issue.