Arboviruses Research Articles

Current Status of La Crosse Virus in North America and Potential for Future Spread.

La Crosse virus (LACV) is an arthropod-borne RNA virus with substantial potential for future spread in North America. La Crosse virus is responsible for La Crosse encephalitis, a leading cause of arboviral encephalitis in children in the United States. Primarily transmitted by Aedes triseriatus (Eastern treehole) mosquitos and amplified by small mammal hosts, LACV has caused infections throughout the upper Midwest and, more recently, the mid-Atlantic and southeastern United States. Notably, in recent years, infections have also been identified increasingly in the Appalachian region. Anthropogenic and environmental factors have likely contributed to recent LACV spread, including the introduction of invasive vector species (especially Ae. albopictus), biotic interactions between and among vector and host species, land-use change, habitat disturbance, increased human travel and transport, and rising global temperatures. Prevention and control strategies, such as increased surveillance of vector and host populations, increased awareness among populations at risk for infection, and increased awareness among physicians are needed to limit future spread. Continued climate change with increases in global temperatures and erratic weather patterns may result in the expansion of competent mosquito vector species and thus could facilitate the geographic spread of LACV.

SERO-PREVALENCE OF DENGUE INFECTION FROM GOVERNMENT HOSPITAL, RAJASTHAN DURING 2022

Background: Viral haemorrhagic fevers are becoming increasingly common in the tropics and subtropics. Dengue fever is currently the most important arthropod‑borne viral disease because of its widespread distribution in more than 100 countries and its potential for extensive outbreaks of life‑threatening disease. Material and Methods: This study was a hospital‑based cross‑sectional study conducted in LaboratoryShrr. R.K.J. Hopsital, Dausa, in Rajasthan, India, between January 2022 to December 2022. The present study included all serum specimens received at laboratory of R.K.J. Hopsital, Dausa, from clinically suspected cases of dengue infection, during this duration. Serum samples were received for serological testing from suspected cases of dengue as advised by consultants from various departments in hospital for laboratory confirmation of suspected cases. Laboratory-confirmed dengue cases were defined as suspected dengue cases with positive dengue serology. Result: The present study analyzed the samples of 1880 of suspected patients during year of 2022. and seropositivity rate of 15% (296/1880) was found out of which 10% (67/648) were seropositive for NS1 antigen and 18% (229/1232) were by IgM ELISA test. The present study revealed trend of cases from August to December 2022 peak of cases was reported in month of September and November. Discussion: The resurgence of dengue has been notable in India and dengue epidemics have been frequently reported in the country both from urban and rural regions. Recent analysis of the past two decades highlighted that, in India, transmission pattern of dengue has changed and widened with shift in peak post-monsoon shifting toward November from October in the recent decade from irregular peak of the previous decade. However, the present pattern in shift of transmission is clear that dengue cannot be considered as a seasonal disease. Conclusions: An alarming rate of increasing emerging and reemerging trends of these arboviral infections are noted in this part of Rajasthan. Hence, the need to focus on proper surveillance, and implementation of prevention and control measure in the country are of utmost priority. Presently, there are no licensed vaccines or antivirals available however, India has initiated several efforts in this direction including traditional medicines. The outcome of this study will help in focusing and improvement of existing surveillance systems and vector control tools, as well as on the development of suitable antiviral agents and formulating candidate vaccine.

Arbovirus infection increases the risk for the development of neurodegenerative disease pathology in the murine model

Alzheimer's disease is classified as a progressive disorder resulting from protein misfolding, also known as proteinopathies. Proteinopathies include synucleinopathies triggered by misfolded amyloid α-synuclein, tauopathies triggered by misfolded tau, and amyloidopathies triggered by misfolded amyloid of which Alzheimer's disease (β-amyloid) is most prevalent. Most neurodegenerative diseases (>90%) are not due to dominantly inherited genetic causes. Instead, it is thought that the risk for disease is a complicated interaction between inherited and environmental risk factors that, with age, drive pathology that ultimately results in neurodegeneration and disease onset. Since it is increasingly appreciated that encephalitic viral infections can have profoundly detrimental neurological consequences long after the acute infection has resolved, we tested the hypothesis that viral encephalitis exacerbates the pathological profile of protein-misfolding diseases. Using a robust, reproducible, and well-characterized mouse model for β-amyloidosis, Tg2576, we studied the contribution of alphavirus-induced encephalitis (TC-83 strain of VEEV to model alphavirus encephalitis viruses) on the progression of neurodegenerative pathology. We longitudinally evaluated neurological, neurobehavioral, and cognitive levels, followed by a post-mortem analysis of brain pathology focusing on neuroinflammation. We found more severe cognitive deficits and brain pathology in Tg2576 mice inoculated with TC-83 than in their mock controls. These data set the groundwork to investigate sporadic Alzheimer's disease and treatment interventions for this infectious disease risk factor.

Modulation of immune responses in the central nervous system by Zika virus, West Nile virus, and dengue virus.

Arthropod-borne viruses (arboviruses) pose significant threats to global public health by causing a spectrum of diseases ranging from mild febrile illnesses to severe neurological complications. Understanding the intricate interplay between arboviruses and the immune system within the central nervous system is crucial for developing effective strategies to combat these infections and mitigate their neurological sequelae. This review comprehensively explores the mechanisms by which arboviruses such as Zika virus, West Nile virus, and Dengue virus manipulate immune responses within the CNS, leading to diverse clinical manifestations.

Immunopathology of emerging and re-emerging viral infections: an updated overview

Humankind has witnessed increased frequency of emerging and re-emerging viral diseases in the past few decades. The major categories of pathogenic emerging and re-emerging viral infections include respiratory, arthropod-borne and bat-borne zoonotic viruses. These viral infections are notorious for causing immune dysregulation and have the potential to mount excessive immune reaction, causing immunopathology that includes tissue injury, systemic inflammation, multi-organ failure and even death. A better understanding of the emerging or re-emerging viral-mediated immunomodulation is necessary for controlling the virus, while preventing severity of the disease associated with exaggerated immune response. In this article, we review the current understanding of emerging and re-emerging respiratory, arboviral and bat-borne zoonotic viruses; and consequent immune dysregulation or immunopathology associated with these viral infections.

Cell fusing agent virus rarely transmits vertically in artificially infected laboratory-colonized Aedes aegypti mosquitoes

BackgroundVertical transmission (VT) of arboviruses (arthropod-borne viruses) can serve as an essential link in the transmission cycle during adverse environmental conditions. The extent of VT among mosquito-borne arboviruses can vary significantly among different virus families and even among different viruses within the same genus. For example, orthobunyaviruses exhibit a higher VT rate than orthoflaviviruses and alphaviruses. Mosquitoes are also the natural hosts of a large number of insect-specific viruses (ISV) that belong to several virus families, including Bunyaviridae, Flaviviridae, and Togaviridae. Cell fusing agent virus (CFAV), an insect-specific orthoflavivirus, displays higher VT rates than other dual-host orthoflaviviruses, such as Zika and dengue viruses. High VT rates require establishment of stabilized infections in the germinal tissues of female vectors. To delve deeper into understanding the mechanisms governing these differences in VT rates and the establishment of stabilized infections, the ovary infection patterns and VT of Zika virus (ZIKV) and CFAV were compared.MethodsLaboratory colonized Aedes aegypti females were infected with either ZIKV or CFAV by intrathoracic injection. Ovary infection patterns were monitored by in situ hybridization using virus-specific probes, and VT was determined by detecting the presence of the virus among the progeny, using a reverse-transcription quantitative polymerase chain reaction (PCR) assay.ResultsBoth ZIKV and CFAV infect mosquito ovaries after intrathoracic injection. Infections then become widespread following a non-infectious blood meal. VT rates of ZIKV are similar to previously reported results (3.33%). CFAV, on the contrary transmits vertically very rarely. VT was not observed in the first gonotrophic cycle following intrathoracic injection, and only rarely in the second gonotrophic cycle. VT of CFAV is mosquito population independent, since similar results were obtained with Aedes aegypti collected from two different geographic locations.ConclusionsAlthough CFAV infects mosquito ovaries, the occurrence of VT remains infrequent in artificially infected Ae. aegypti, despite the observation of high VT rates in field-collected mosquitoes. These results suggest that infections of insect-specific viruses are stabilized in mosquitoes by some as yet unidentified mechanisms.Graphical

Central nervous system infections in the tropics.

Emerging and re-emerging central nervous system (CNS) infections are a major public health concern in the tropics. The reasons for this are myriad; climate change, rainfall, deforestation, increased vector density combined with poverty, poor sanitation and hygiene. This review focuses on pathogens, which have emerged and re-emerged, with the potential for significant morbidity and mortality. In recent years, multiple acute encephalitis outbreaks have been caused by Nipah virus, which carries a high case fatality. Arboviral infections, predominantly dengue, chikungunya and Zika are re-emerging increasingly especially in urban areas due to changing human habitats, vector behaviour and viral evolution. Scrub typhus, another vector borne disease caused by the bacterium Orientia tsutsugamushi , is being established as a leading cause of CNS infections in the tropics. A syndromic and epidemiological approach to CNS infections in the tropics is essential to plan appropriate diagnostic tests and management. Rapid diagnostic tests facilitate early diagnosis and thus help prompt initiation and focusing of therapy to prevent adverse outcomes. Vector control, cautious urbanization and deforestation, and reducing disturbance of ecosystems can help prevent spread of vector-borne diseases. Regional diagnostic and treatment approaches and specific vaccines are required to avert morbidity and mortality.

Metagenomic analysis of individual mosquito viromes reveals the geographical patterns and drivers of viral diversity.

Mosquito transmitted viruses are responsible for an increasing burden of human disease. Despite this, little is known about the diversity and ecology of viruses within individual mosquito hosts. Here, using a meta-transcriptomic approach, we determined the viromes of 2,438 individual mosquitoes (81 species), spanning ~4,000 km along latitudes and longitudes in China. From these data we identified 393 viral species associated with mosquitoes, including 7 (putative) species of arthropod-borne viruses (that is, arboviruses). We identified potential mosquito species and geographic hotspots of viral diversity and arbovirus occurrence, and demonstrated that the composition of individual mosquito viromes was strongly associated with host phylogeny. Our data revealed a large number of viruses shared among mosquito species or genera, enhancing our understanding of the host specificity of insect-associated viruses. We also detected multiple virus species that were widespread throughout the country, perhaps reflecting long-distance mosquito dispersal. Together, these results greatly expand the known mosquito virome, linked viral diversity at the scale of individual insects to that at a country-wide scale, and offered unique insights into the biogeography and diversity of viruses in insect vectors.

Multiplex PCR method for MinION sequencing of Bagaza virus isolated from wild caught mosquitoes in South Africa

Bagaza virus (BAGV) is a mosquito-borne orthoflavivirus known to occur in regions of southern Europe, Africa, India and the Middle East. The virus has been associated with neurological disease and fatalities in various wild bird species. Association with human disease is not confirmed although limited serological evidence has suggested human infection. Surveillance programs for screening mosquitoes for evidence of arbovirus infection play an important role in providing information regarding the circulation and spread of viruses in specific regions. BAGV was detected in a mosquito pool during surveillance of mosquitoes collected in central South Africa between November 2019 and March 2023. Homogenized mosquito pools were screened for flaviviral RNA using conventional RT-PCR and virus isolation was attempted on positive samples. BAGV was detected and subsequently isolated using cell culture. A multiplex tiling PCR method for targeted enrichment using a PCR based or amplicon sequencing approach of the complete genome of BAGV was developed and optimized. Primers were designed using alignment of complete genome sequence data retrieved from GenBank to identify suitable primer sites that would generate overlapping fragments spanning the complete genome. Six forward primers and eight reverse primers were identified that target the complete genome and amplified nine overlapping fragments, that ranged in length from 1954 to 2039 with an overlap ranging from 71 to 711 base pairs. The design strategy included multiple forward and reverse primer pairs for the 5’ and 3’ ends. Phylogenetic analysis with other isolates was performed and BAGV isolate VBD 74/23/3 was shown to share high similarity with previous BAGV isolates from all regions, with genetic distance ranging from 0.026 to 0.083. VBD 74/23/3 was most closely related to previous isolates from southern Africa, ZRU96/16/2 isolated from a post-mortem sample from a pheasant in 2016 and MP-314-NA-2018 isolated from mosquitoes in northwestern Namibia with genetic distance 0.0085 and 0.016 respectively. Currently there is limited complete genome sequence data available for many of the arboviruses circulating in Africa. The multiplex tiling method provided a simple and cost-effective method for obtaining complete genome sequence. This method can be readily applied to other viruses using sequence data from publicly available databases and would have important application facilitating genomic surveillance of arboviruses in low resource countries.

Current diagnostics and biomarkers for arboviral infections (a review on Dengue, Zika, West Nile and Chikungunya viruses)

Arboviral infections, transmitted to humans primarily through arthropod vectors, constitute a significant global health threat. Arboviruses, such as Dengue, Zika, Chikungunya, and West Nile viruses, continue to cause widespread outbreaks, necessitating advanced diagnostic tools. Emerging technologies including Lab On A Chip (LOC), Lab On A Disc (LOAD), Microfluidic Paper-Based Analytical Devices (µPADS), Lateral Flow Devices, CRISPR-CAS 12/13, Quartz crystal microbalance (QCM), and Nano-Technology are evaluated for their potential to enhance arboviral diagnosis, offering rapid, accurate, and point-of-care solutions. Furthermore, the identification of robust biomarkers, including Inflammatory Cytokines, Antibodies, Endothelial Activation Products and Indicators of Tissue or Organ Damage, is crucial for improving the understanding of disease pathogenesis, prognosis, and treatment response. A comprehensive analysis of potential diagnostics and biomarkers for arboviral infections sheds light on the evolving strategies to combat these medically significant diseases, ultimately contributing to more effective surveillance, diagnosis and management worldwide.

Crimean-Congo Haemorrhagic Fever Virus: From Genomic Insights to Control Strategies

Crimean-Congo hemorrhagic fever virus (CCHFV) is a life-threatening arthropod-borne virus transmitted by tick bites or contact with blood or tissues of viraemic individuals and animals. CCHFV continues its existence in a broad region with sporadic cases or outbreaks. CCHFV infection is observed frequently as an asymptomatic, but sudden severe disease characterised by haemorrhagic can occur. Diagnostic methods employ enzyme-linked immunosorbent assay (ELISA) and real-time reverse transcription-polymerase chain reaction (RT-PCR). Although ribavirin has been recommended in treatment besides supportive therapy approaches, no antiviral or vaccine for CCHF is currently approved. This review demonstrates general knowledge of CCHFV, summarising its molecular biology, pathogenesis, diagnosis, epidemiology, sustaining and transmission, treatment and prevention strategies, including vaccine candidates.

Immunoinformatics and computational approaches driven designing a novel vaccine candidate against Powassan virus

Powassan virus (POWV) is an arthropod-borne virus (arbovirus) capable of causing severe illness in humans for severe neurological complications, and its incidence has been on the rise in recent years due to climate change, posing a growing public health concern. Currently, no vaccines to prevent or medicines to treat POWV disease, emphasizing the urgent need for effective countermeasures. In this study, we utilize bioinformatics approaches to target proteins of POWV, including the capsid, envelope, and membrane proteins, to predict diverse B-cell and T-cell epitopes. These epitopes underwent screening for critical properties such as antigenicity, allergenicity, toxicity, and cytokine induction potential. Eight selected epitopes were then conjugated with adjuvants using various linkers, resulting in designing of a potentially stable and immunogenic vaccine candidate against POWV. Moreover, molecular docking, molecular dynamics simulations, and immune simulations revealed a stable interaction pattern with the immune receptor, suggesting the vaccine's potential to induce robust immune responses. In conclusion, our study provided a set of derived epitopes from POWV’s proteins, demonstrating the potential for a novel vaccine candidate against POWV. Further in vitro and in vivo studies are warranted to advance our efforts and move closer to the goal of combatting POWV and related arbovirus infections.

Epidemiological situation of natural focal infections in the Volgograd region in 2023

Objective: analysis of epizootiological and epidemiological aspects of natural focal infections, namely plague, tularemia, HFRS, West Nile fever, Crimean hemorrhagic fever, Ixodic tick-borne borreliosis, Cu fever, leptospirosis and rabies, in the Volgograd region over 10 months in 2023.Materials and methods: the article analyzes the epidemiological manifestations of natural focal infections (NFI) in the Volgograd region for 10 months of 2023. The work uses official statistical data from institutions of Rospotrebnadzor of the Volgograd region on NFI for 2023. The main research method is epidemiological analysis.Results: the numbers of small mammals, potential carriers of NFI, on the territory of the Volgograd region in the 2023 season were within the same indicators of the previous year (SIPY), while the number of ticks in the spring-summer period was higher than the SIPY, but in the fall the number of arthropods in stationary points was lower than in previous seasons. The number of mosquitoes carrying arbovirus infections exceeded the long-term average. When studying environmental objects for the presence of markers of NFI pathogens, a slight decrease in the proportion of positive samples was noted compared to SIPY for all nosological forms. Over the 10 months of this year, there has been a deterioration in the epidemiological situation in the Volgograd region for several infections compared to the same period in 2022. There were 18 cases of West Nile fever (WNF), 10 cases of ixodid tick-borne borreliosis (ITB), and 6 cases of hemorrhagic fever with renal syndrome (HFRS). No patients with plague, tularemia, rabies, leptospirosis, Crimean hemorrhagic fever (CHF) and Q fever were identified.Conclusion: the presence of natural foci of dangerous infectious diseases of varying degrees of activity on the territory of the Volgograd region requires constant monitoring and an adequate response to changes in the foci in order to prevent complications of the epidemiological situation due to NFI.

Alpha-mannosidase-2 modulates arbovirus infection in a pathogen- and Wolbachia-specific manner in Aedes aegypti mosquitoes.

Multiple Wolbachia strains can block pathogen infection, replication and/or transmission in Aedes aegypti mosquitoes under both laboratory and field conditions. However, Wolbachia effects on pathogens can be highly variable across systems and the factors governing this variability are not well understood. It is increasingly clear that the mosquito host is not a passive player in which Wolbachia governs pathogen transmission phenotypes; rather, the genetics of the host can significantly modulate Wolbachia-mediated pathogen blocking. Specifically, previous work linked variation in Wolbachia pathogen blocking to polymorphisms in the mosquito alpha-mannosidase-2 (αMan2) gene. Here we use CRISPR-Cas9 mutagenesis to functionally test this association. We developed αMan2 knockouts and examined effects on both Wolbachia and virus levels, using dengue virus (DENV; Flaviviridae) and Mayaro virus (MAYV; Togaviridae). Wolbachia titres were significantly elevated in αMan2 knockout (KO) mosquitoes, but there were complex interactions with virus infection and replication. In Wolbachia-uninfected mosquitoes, the αMan2 KO mutation was associated with decreased DENV titres, but in a Wolbachia-infected background, the αMan2 KO mutation significantly increased virus titres. In contrast, the αMan2 KO mutation significantly increased MAYV replication in Wolbachia-uninfected mosquitoes and did not affect Wolbachia-mediated virus blocking. These results demonstrate that αMan2 modulates arbovirus infection in A. aegypti mosquitoes in a pathogen- and Wolbachia-specific manner, and that Wolbachia-mediated pathogen blocking is a complex phenotype dependent on the mosquito host genotype and the pathogen. These results have a significant impact for the design and use of Wolbachia-based strategies to control vector-borne pathogens.

Guide to Utilization of the Microbiology Laboratory for Diagnosis of Infectious Diseases: 2024 Update by the Infectious Diseases Society of America (IDSA) and the American Society for Microbiology (ASM).

The critical nature of the microbiology laboratory in infectious disease diagnosis calls for a close, positive working relationship between the physician and the microbiologists who provide enormous value to the health care team. This document, developed by experts in both adult and pediatric laboratory and clinical medicine, provides information on which tests are valuable and in which contexts, and on tests that add little or no value for diagnostic decisions. Sections are divided into anatomic systems, including Bloodstream Infections and Infections of the Cardiovascular System, Central Nervous System Infections, Ocular Infections, Soft Tissue Infections of the Head and Neck, Upper Respiratory Infections, Lower Respiratory Tract infections, Infections of the Gastrointestinal Tract, Intraabdominal Infections, Bone and Joint Infections, Urinary Tract Infections, Genital Infections, and Skin and Soft Tissue Infections; or into etiologic agent groups, including arboviral Infections, Viral Syndromes, and Blood and Tissue Parasite Infections. Each section contains introductory concepts, a summary of key points, and detailed tables that list suspected agents; the most reliable tests to order; the samples (and volumes) to collect in order of preference; specimen transport devices, procedures, times, and temperatures; and detailed notes on specific issues regarding the test methods, such as when tests are likely to require a specialized laboratory or have prolonged turnaround times. In addition, the pediatric needs of specimen management are also addressed. There is redundancy among the tables and sections, as many agents and assay choices overlap. The document is intended to serve as a reference to guide physicians in choosing tests that will aid them to diagnose infectious diseases in their patients.

MR Imaging Patterns and Prognosis in Powassan Virus Encephalitis.

Powassan virus (POWV) encephalitis is an arbovirus infection and the only tick-borne encephalitis serogroup which is present in mainland North America. The magnetic resonance (MR) imaging described with POWV encephalitis is varied, nonspecific, and limited in number, and as such, imaging patterns and outcomes with this arbovirus infection are not well appreciated. A case report and literature review of the MR imaging associated with POWV encephalitis and correlate of the MR pattern with outcome is considered. The cerebellar dominant MR imaging pattern was identified in 50% of POWV encephalitis cases and was associated with a 60% fatality rate. POWV encephalitis with prominent cerebellar involvement on MR imaging responded to intravenous steroid. A cerebellar dominant MR pattern in POWV encephalitis was common, associated with a poor prognosis, and recognition could change management from supportive to life-saving.

Potential of Ilhéus virus to emerge

Ilhéus virus (ILHV)(Flaviviridae:Orthoflavivirus) is an arthropod-borne virus (arbovirus) endemic to Central and South America and the Caribbean. First isolated in 1944, most of our knowledge derives from surveillance and seroprevalence studies. These efforts have detected ILHV in a broad range of mosquito and vertebrate species, including humans, but laboratory investigations of pathogenesis and vector competence have been lacking. Here, we develop an immune intact murine model with several ages and routes of administration. Our model closely recapitulates human neuroinvasive disease with ILHV strain- and mouse age-specific virulence, as well as a uniformly lethal Ifnar−/− A129 immunocompromised model. Replication kinetics in several vertebrate and invertebrate cell lines demonstrate that ILHV is capable of replicating to high titers in a wide variety of potential host and vector species. Lastly, vector competence studies provide strong evidence for efficient infection of and potential transmission by Aedes species mosquitoes, despite ILHV's phylogenetically clustering with Culex vectored flaviviruses, suggesting ILHV is poised for emergence in the neotropics.

Dengue hemorrhagic fever with rectus sheath hematoma: A case report

Rationale: Acute pain is a medical emergency that requires prompt abdominal evaluation and management. Dengue, a mosquito-borne arboviral infection, can lead to complications such as acute abdominal pain. Patient concerns: A 72-year-old hypertensive female presented with high-grade intermittent fever with chills and rigors for four days. She was diagnosed with dengue fever (NS1Ag-reactive) the day before admission. A contrast-enhanced computed tomography of the abdomen showed a hematoma along the rectus sheath which was managed conservatively as per surgical opinion. Diagnosis: Dengue hemorrhagic fever with rectus sheath hematoma. Interventions: Blood transfusion and fluid therapy. Outcomes: Ten days after discharge, the patient reproted no pain in the right iliac fossa and the size of the hematoma was significantly reduced. Lessons: Although it is rarely seen as a cause of acute abdomen, complaints of adnominal pain should never be ignored in critical or convalescent phase of dengue fever. Radiological investigations should be promptly conducted as hematoma is often difficult to be diagnosed clinically. Delay in diagnosis of rectus sheath hematoma can be fatal.

Prevalence of arboviruses in sickle cell disease patients from two different regions of Brazil, the North and Northeast

Sickle Cell Disease (SCD) is a hereditary disease characterized by extravascular and intravascular hemolysis and clinical variability, from mild pain to potentially life-threatening. Arboviruses include mainly Zika (ZIKV), Chikungunya (CHKV), and Dengue (DENV) virus, and are considered a public and social health problem. The present cross-sectional observational study aimed to investigate the prevalence of arbovirus infection in SCD patients from two Brazilian cities, Salvador and Manaus located in Bahia and Amazonas states respectively. A total of 409 individuals with SCD were included in the study, and 307 (75.06 %) patients tested positive for DENV-IgG, 161 (39.36 %) for ZIKV-IgG, and 60 (14.67 %) for CHIKV-IgG. Only one individual was positive for DENV-NS1 and another for DENV-IgM, both from Salvador. No individuals had positive serology for ZIKV-IgM or CHIKV-IgM. Arbovirus positivity by IgG testing revealed that the SCD group presented high frequencies in both cities. Interestingly, these differences were only statistically significant for ZIKV-IgG (p = 0.023) and CHIKV-IgG (p = 0.005) among SCD patients from Manaus. The reshaping of arbovirus from its natural habitat by humans due to disorderly urban expansion and the ease of international Mobility has been responsible for facilitating the spread of vector-borne infectious diseases in humans. We found the need for further studies on arboviruses in this population to elucidate the real association and impact, especially in acute infection. We hope that this study will contribute to improvements in the personalized clinical follow-up of SCD patients, identifying the influence of arbovirus infection in severe disease manifestations.

Screening and identification of persistent viruses in cell lines derived from medically important arthropods.

Arthropod-derived cell lines serve as crucial tools for studying arthropod-borne viruses (arboviruses). However, it has recently come to light that certain cell lines harbor persistent infections of arthropod-specific viruses, which do not cause any apparent cytopathic effects. Moreover, some of these persistent viral infections either inhibit or promote the growth of arboviruses. Therefore, it is of utmost importance to identify the presence of such persistent viruses and understand their impact on arboviral infections. In this study, we conducted a comprehensive virome analysis of several arthropod-derived cell lines, including mosquito-derived NIID-CTR, Ar-3, MSQ43, NIAS-AeAl-2, CCL-126 cells, and tick-derived IDE8 cells, along with flesh fly-derived NIH-Sape-4 cells. The aim was to determine if these cells were infected with persistent viruses. The results revealed the presence of 15 persistent viruses in NIID-CTR, Ar-3, MSQ43, NIAS-AeAl-2, and IDE8 cells. Among these, 11 were already known arthropod-specific viruses, while the remaining 4 were novel viruses belonging to Orthophasmavirus, Rhabdoviridae, Totiviridae, and Bunyavirales. In contrast, CCL-126 and NIH-Sape-4 cells appeared to be free of viral infections. This study provides valuable insights into the diversity and latency of arthropod-specific viruses within arthropod-derived cell lines. Further investigations are required to explore persistent viral infections in other arthropod-derived cell cultures and their effects on arbovirus replication. Understanding these factors will enhance the accuracy and reliability of experimental data obtained using these cell lines.