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The yellow fever virus (YFV) epidemic in Brazil is the largest in decades. The recent discovery of YFV in Brazilian Aedes species mosquitos highlights a need to monitor the risk of reestablishment of urban YFV transmission in the Americas. We use a suite of epidemiological, spatial, and genomic approaches to characterize YFV transmission. We show that the age and sex distribution of human cases is characteristic of sylvatic transmission. Analysis of YFV cases combined with genomes generated locally reveals an early phase of sylvatic YFV transmission and spatial expansion toward previously YFV-free areas, followed by a rise in viral spillover to humans in late 2016. Our results establish a framework for monitoring YFV transmission in real time that will contribute to a global strategy to eliminate future YFV epidemics.

In 2011, vaccinia virus caused an outbreak of bovine vaccinia, affecting dairy cattle and dairy workers in Brazil. Genetic and phenotypic analyses identified this isolate as distinct from others recently identified, thereby reinforcing the hypothesis that different vaccinia virus strains co-circulate in Brazil. [ABSTRACT FROM AUTHOR]

Dengue virus type 3 genotype I was detected in Brazil during epidemics in 2002-2004. To confirm this finding, we identified this virus genotype in naturally infected field-caught Aedes aegypti mosquitoes and eggs. Results showed usefulness of virus investigations in vectors as a component of active epidemiologic surveillance. [ABSTRACT FROM AUTHOR]

To detect orthopoxvirus in the Brazilian Amazon, we conducted a serosurvey of 344 wild animals. Neutralizing antibodies against orthopoxvirus were detected by plaque-reduction neutralizing tests in 84 serum samples. Amplicons from 6 monkey samples were sequenced. These amplicons identified vaccinia virus genetically similar to strains from bovine vaccinia outbreaks in Brazil. [ABSTRACT FROM AUTHOR]

Dengue serotype 3 viruses were isolated from patients in Brazil from 2002 through 2004. On the basis of phylogenetic analyses, these isolates were assigned genotype 1. This genotype had never been reported in South America before. Its appearance indicates a major risk factor for dengue epidemics and severe disease. [ABSTRACT FROM AUTHOR]

In the context of the virosphere, viral particles can compete for host cells. In this scenario, some viruses block the entry of exogenous virions upon infecting a cell, a phenomenon known as superinfection inhibition. The molecular mechanisms associated with superinfection inhibition vary depending on the viral species and the host, but generally, blocking superinfection ensures the genetic supremacy of the virus's progeny that first infects the cell. Giant amoeba-infecting viruses have attracted the scientific community's attention due to the complexity of their particles and genomes. However, there are no studies on the occurrence of superinfection and its inhibition induced by giant viruses. This study shows that mimivirus, moumouvirus, and megavirus, exhibit different strategies related to the infection of Acanthamoeba . For the first time, we have reported that mimivirus and moumouvirus induce superinfection inhibition in amoebas. Interestingly, megaviruses do not exhibit this ability, allowing continuous entry of exogenous virions into infected amoebas. Our investigation into the mechanisms behind superinfection blockage reveals that mimivirus and moumouvirus inhibit amoebic phagocytosis, leading to significant changes in the morphology and activity of the host cells. In contrast, megavirus-infected amoebas continue incorporating newly formed virions, negatively affecting the available viral progeny. This effect, however, is reversible with chemical inhibition of phagocytosis. This work contributes to the understanding of superinfection and its inhibition in mimivirus, moumouvirus, and megavirus, demonstrating that despite their evolutionary relatedness, these viruses exhibit profound differences in their interactions with their hosts.IMPORTANCESome viruses block the entry of new virions upon infecting a cell, a phenomenon known as superinfection inhibition. Superinfection inhibition in giant viruses has yet to be studied. This study reveals that even closely related viruses, such as mimivirus, moumouvirus, and megavirus, have different infection strategies for Acanthamoeba . For the first time, we have reported that mimivirus and moumouvirus induce superinfection inhibition in amoebas. In contrast, megaviruses do not exhibit this ability, allowing continuous entry of exogenous virions into infected amoebas. Our investigation shows that mimivirus and moumouvirus inhibit amoebic phagocytosis, causing significant changes in host cell morphology and activity. Megavirus-infected amoebas, however, continue incorporating newly formed viruses, affecting viral progeny. This research enhances our understanding of superinfection inhibition in these viruses, highlighting their differences in host interactions., Competing Interests: The authors declare no conflict of interest.

The monkeypox virus (MPXV) outbreak, primarily endemic to Africa, has spread globally, with Brazil reporting the second-highest number of cases. The emergence of MPXV in non-endemic areas has raised concerns, particularly due to the co-circulation of other exanthematous viruses such as varicella-zoster virus (VZV) and molluscum contagiosum virus (MOCV). To perform an accurate differential diagnosis of MPXV during the ongoing outbreak in Minas Gerais, Brazil, a 5PLEX qPCR assay targeting orthopoxviruses (OPV), VZV, and MOCV was used to retrospectively analyze all clinical samples that tested negative for MPXV in the initial screening conducted at Funed. In summary, our study analyzed 1,175 clinical samples received from patients suspected of MPXV infection and found a positivity rate of 33.8% (397 samples) for MPXV using the non-variola qPCR assay. Testing the 778 MPXV-negative clinical samples using the 5PLEX qPCR assay revealed that 174 clinical samples (22.36%) tested positive for VZV. MOCV DNA was detected in 13 and other OPV in 3 clinical samples. The sequencing of randomly selected amplified clinical samples confirmed the initial molecular diagnosis. Analysis of patient profiles revealed a significant difference in the median age between groups testing positive for MPXV and VZV and a male predominance in MPXV cases. The geographic distribution of positive cases was concentrated in the most populous mesoregions of Minas Gerais state. This study highlights the challenges posed by emerging infectious diseases. It emphasizes the importance of epidemiological surveillance and accurate diagnosis in enabling timely responses for public health policies and appropriate medical care., Importance: Brazil ranks second in the number of cases during the global monkeypox epidemic. The study, conducted in Minas Gerais, the second most populous state in Brazil with over 20 million inhabitants, utilized differential diagnostics, revealing a significant number of positive cases for other exanthematous viruses and emphasizing the need for accurate diagnoses. During the study, we were able to assess the co-circulation of other viruses alongside monkeypox, including varicella-zoster virus, molluscum contagiosum virus, and other orthopoxviruses. The significance of the research is underscored by the concentration of positive cases in populous areas, highlighting the challenges posed by emerging infectious diseases. This demographic context further amplifies the importance of the research in guiding public health policies and medical interventions, given the substantial population at risk. The study not only addresses a global concern but also holds critical implications for a state with such a large population and geographic expanse within Brazil. Overall, the study emphasizes the pivotal role of surveillance and precise diagnosis in guiding effective public health responses and ensuring appropriate medical interventions., Competing Interests: P.A. and M.B.A. are employees of Bio-Manguinhos (Fundação Oswaldo Cruz/FIOCRUZ), the institution responsible for the development and provision of the Kit Molecular 5PLEX OPXV/MPXV/VZV/MOCV/RP to the BrMoH. However, there was no involvement or interference from this institution in the execution of the experiments or the writing of the manuscript.

Herpes simplex virus 1 (HSV-1) or simplexvirus humanalpha 1 is a neurotropic virus that is responsible for orofacial infections in humans. More than 70% of the world's population may have seropositivity for HSV-1, and this virus is a leading cause of sporadic lethal encephalitis in humans. The role of toll-like receptors (TLRs) in defending against HSV-1 infection has been explored, including the consequences of lacking these receptors or other proteins in the TLR pathway. Cell and mouse models have been used to study the importance of these receptors in combating HSV-1, how they relate to the innate immune response, and how they participate in the orchestration of the adaptive immune response. Myeloid differentiation factor 88 (MyD88) is a protein involved in the downstream activation of TLRs and plays a crucial role in this signaling. Mice with functional MyD88 or TLR2 and TLR9 can survive HSV-1 infection. However, they can develop encephalitis and face a 100% mortality rate in a dose-dependent manner when MyD88 or TLR2 plus TLR9 proteins are non-functional. In TLR2/9 knockout mice, an increase in chemokines and decreases in nitric oxide (NO), interferon (IFN) gamma, and interleukin 1 (IL-1) levels in the trigeminal ganglia (TG) have been correlated with mortality., Competing Interests: The authors declare no conflict of interest., (© 2024 The Author(s). Published by IMR Press.)

Around three billion people are at risk of infection by the dengue virus (DENV) and potentially other flaviviruses. Worldwide outbreaks of DENV, Zika virus (ZIKV), and yellow fever virus (YFV), the lack of antiviral drugs, and limitations on vaccine usage emphasize the need for novel antiviral research. Here, we propose a consensus virtual screening approach to discover potential protease inhibitors (NS3 pro ) against different flavivirus. We employed an in silico combination of a hologram quantitative structure-activity relationship (HQSAR) model and molecular docking on characterized binding sites followed by molecular dynamics (MD) simulations, which filtered a data set of 7.6 million compounds to 2,775 hits. Lastly, docking and MD simulations selected six final potential NS3 pro inhibitors with stable interactions along the simulations. Five compounds had their antiviral activity confirmed against ZIKV, YFV, DENV-2, and DENV-3 (ranging from 4.21 ± 0.14 to 37.51 ± 0.8 μM), displaying aggregator characteristics for enzymatic inhibition against ZIKV NS3 pro (ranging from 28 ± 7 to 70 ± 7 μM). Taken together, the compounds identified in this approach may contribute to the design of promising candidates to treat different flavivirus infections.

Background: Dengue virus (DENV) is a Flaviviridae member classified into four antigenically distinct serotypes (DENV 1, 2, 3, and 4) and further subdivided genotypes. DENV3 is subdivided into four or five genotypes, depending on the classification adopted. Despite their high genetic proximity, as revealed by phylogenetic complete polyprotein analysis, DENV3 MG-20 and DENV3 PV_BR showed different neurovirulence in mice models. Our group identified six amino acid mutations in protein E, including the E62K and E123Q, which may affect interactions of hydrophobic clusters on domain II, thus leading to the observed differences in the studied viruses., Methods: Human glioblastoma cells (U251) derived from a malignant glioblastoma tumor by explant technique were infected by the DENV3 GIL1 isolates DENV3 MG-20 and DENV3 PV_BR and analyzed by plaque assays and titration, optical, immunofluorescence, and transmission electronic microscopy., Results: The two isolates showed different cytopathic effects (CPE) and fusogenic patterns, further confirmed by indirect immunofluorescence. Transmission electron microscopy revealed intense cytopathic effects in DENV3 MG-20 infected U251 cells, displaying endoplasmic reticulum hypertrophy and turgid vesicles with proteins and multiple viruses, distinct from DENV3 PV_BR infected cells. It is hypothesized that the different amino acids in the DENV3 MG-20 isolate are related to an increased membrane fusion ability in viral infection, thus facilitating immune system evasion and increased chances of central nervous system cell infection., Conclusion: These results emphasize the biological differences between the isolates, which could be a critical factor in host-virus interaction and severe dengue development. Our study presents comparative results of highly similar isolates with the potential to generate more subsidies for a deeper understanding of the DENV pathogenesis. The neurotropism of the isolate DENV3 MG-20 (belonging to the DENV3 GI L1 genotype) showing infection of nervous system cells (U251) could contribute to understanding neurological dengue disease., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Background: Acute bacterial meningitis (ABM) causes excessive activation of N-methyl-D-aspartate receptors (NMDAr), leading to cortical and hippocampal neuron death. As opposite, enteroviral meningitis is more frequently benign. The kynurenine (KYN) pathway is the major catabolic route of tryptophan (TRP) and some of its metabolites are agonists or antagonists of NMDAr., Methods: In order to investigate the pathogen-specific patterns of KYN pathway modulation in the central nervous system of children with acute meningococcal (MM), pneumococcal (PM) or enteroviral (VM) meningitis, the cerebrospinal fluid (CSF) concentrations of TRP, KYN, kynurenic acid (KYNA) and quinolinic acid (QUINA) were evaluated by ultra-high performance liquid chromatography (uHPLC) coupled to mass spectrometry. In addition, CSF levels of IL-6, IL-10 and TNF-α were quantified by multi-analyte flow assay. The data was mined and integrated using statistical and machine learning methods., Results: The three forms of meningitis investigated herein up-regulated the neurotoxic branch of the KYN pathway within the intrathecal space. However, this response, represented by the concentration of QUINA, was six and nine times higher in PM patients compared to MM or VM, respectively. CSF levels of IL-6, TNF-α, and IL-10 were increased in MM and PM patients when compared to controls. In VM, CSF IL-6 and IL-10, but not TNF-α were increased compared to controls, although not reaching the high levels found in bacterial meningitis. No correlation was found between the concentrations or the ratios of any pair of KYN metabolites and any cytokine or standard cytochemical parameter tested., Conclusions: CNS infection with meningococci, pneumococci, and enteroviruses intrathecally activate the KYN pathway, favoring its neurotoxic branch. However, in PM, higher CSF levels of QUINA, compared to MM and VM, may contribute to its poorer neurologic outcome., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Since 1999, Vaccinia virus (VACV) has been described as a causative agent of bovine vaccinia (BV), a zoonotic disease that occurs mainly in rural areas of Brazil. However, the circulation of VACV in urban environments and its associated burden has been poorly explored. Moreover, the current monkeypox (mpox) outbreak has raised questions regarding the immune status of the worldwide population previous vaccinated against smallpox. Hence, we conducted a cross-sectional study to better understand the prevalence of anti-OPV neutralizing antibodies (NA) and related exposure factors in a susceptible urban population of Brazil. A total of 372 individuals were sampled, yielding an overall seroprevalence of 16.9% (CI95% = 13.4-21.1), and antibodies titers ranging from 100 to 800 neutralizing units/mL. The prevalence of NA among individuals potentially vaccinated against smallpox (≥36 years old [yo]) was 24.9% (IC 95% = 19.5-31.2), and among those unvaccinated (<36yo) was 6.7% (IC 95% = 3.7-11.8). Interestingly, contact with horses was pointed out as an exposure factor for the presence of NA, however, the multivariate logistic regression analysis indicated that age ≥36yo and the presence of vaccine take were independently associated with the presence of anti-OPV NA. Our findings suggest that vulnerable populations could be subclinically exposed to VACV in urban areas, drawing attention to alternative routes of zoonotic VACV exposure. Our data is also important for better strategies to mitigate zoonotic OPV infections mainly among vulnerable populations., (© 2023 Wiley Periodicals LLC.)

Phylogenetic analysis of 34 monkeypox virus genome sequences isolated from patients in Minas Gerais, Brazil, revealed initial importation events in early June 2022, then community transmission within the state. All generated genomes belonged to the B.1 lineage responsible for a global mpox outbreak. These findings can inform public health measures.

This study evaluates the range of neurological manifestation in children with COVID-19 (neuro-COVID-19) both with and without the multisystem inflammatory syndrome (MIS-C) and the persistence of symptoms after hospital discharge. The study was conducted as a prospective study of children and adolescents under 18 years of age who were admitted to a children's hospital for infectious diseases from January 2021 to January 2022. The children had no previous neurological or psychiatric disorders. Out of the 3021 patients evaluated, 232 were confirmed to have COVID-19 and 21 of these patients (9%) showed neurological manifestations associated with the virus. Of these 21 patients, 14 developed MIS-C, and 7 had neurological manifestations unrelated to MIS-C. There was no statistical difference regarding the neurological manifestations during hospitalization and outcomes between patients with neuro-COVID-19 who had or did not have MIS-C, except for seizures that occurred more frequently in patients with neuro-COVID-19 without MIS-C (p-value = 0.0263). One patient died, and 5 patients still had neurological or psychiatric manifestations at discharge, which persisted for up to 7 months. The study highlights that SARS-CoV-2 infection can affect the central and peripheral nervous system, particularly in children and adolescents with MIS-C, and that it is crucial to be vigilant for long-term adverse outcomes, as the neurological and psychiatric effects of COVID-19 in children are emerging during an important stage of brain development., (© 2023. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

According to the World Health Organisation, as of October 2022, there have been 55,560,329 reported cases of SARS-COV-2 in patients under 19 years old. It is estimated that about 0.06% of these patients may develop MIS-C, representing more than 2 million children worldwide. This systematic review and meta-analysis examined the pooled prevalence of cardiovascular manifestation and cardiac complications in children hospitalised with MIS-C. The PROSPERO register number is CRD42022327212. We included case-report studies, case-control studies, cohort studies, and cross-sectional studies, as well as clinical trials or studies describing cardiac manifestations of MIS-C and its sequelae in a paediatric population. Initially, 285 studies were selected, but there were 154 duplicates, and 81 were excluded because they did not fit the eligibility criteria. Thus, 50 studies were selected for review, and 30 were included in the meta-analysis. A total sample size of 1445 children was included. The combined prevalence of myocarditis or pericarditis was 34.3% (95% CI: 25.0%-44.2%). The combined prevalence for echocardiogram anomalies was 40.8% (95% CI: 30.5%-51.5%), that of Kawasaki disease presentation was 14.8% (95% CI: 7.5%-23.7%), and that of coronary dilation was 15.2% (95% CI: 11.0%-19.8%). The rate of electrocardiogram anomalies was 5.3% (95% CI: 0.8%-12.3%), and the mortality rate was 0.5% (CI 95%: 0%-1.2%). Furthermore, 186 children still had complications at discharge, with a combined prevalence of such long-lasting manifestations of 9.3% (95% CI: 5.6%-13.7%). Studies that assess whether these children will have an increased cardiovascular risk with a greater chance of acute myocardial infarction, arrhythmias, or thrombosis will be essential for healthcare planning., (© 2023 John Wiley & Sons Ltd.)

In early May 2022, the first worldwide monkeypox virus (MPXV) outbreak was reported, with different clinical aspects from previously studied human monkeypox infections. Despite monkeypox medical importance, much of its biological aspects remain to be further investigated. In the present work, we evaluated ultrastructural aspects of MPXV asynchronous infections in Vero cells by transmission electron microscopy (TEM). The viral strain was isolated from a male patient infected during the 2022 outbreak. TEM analysis showed: (i) adhered intracellular mature virus particles before entry of the host cell; (ii) a reorganization of the rough endoplasmic reticulum cisternae into the so-called "mini-nuclei" structure associated with genome replication; and (iii) noticeably different sites within the viral factory presenting granular or fibrillar aspects. We also observed viral crescents, different MPXV particle morphotypes, and cellular alterations induced by infection, such as changes in the cytoskeleton structure and multimembrane vesicles abundance. Taken together, to the best of our knowledge, these results revealed for the first-time ultrastructural aspects of different steps of the MPXV cycle., (© 2023 Wiley Periodicals LLC.)

Aedes aegypti and A. albopictus mosquitoes are the main vectors for dengue virus (DENV) and other arboviruses, including Zika virus (ZIKV). Understanding the factors that affect transmission of arboviruses from mosquitoes to humans is a priority because it could inform public health and targeted interventions. Reasoning that interactions among viruses in the vector insect might affect transmission, we analysed the viromes of 815 urban Aedes mosquitoes collected from 12 countries worldwide. Two mosquito-specific viruses, Phasi Charoen-like virus (PCLV) and Humaita Tubiacanga virus (HTV), were the most abundant in A. aegypti worldwide. Spatiotemporal analyses of virus circulation in an endemic urban area revealed a 200% increase in chances of having DENV in wild A. aegypti mosquitoes when both HTV and PCLV were present. Using a mouse model in the laboratory, we showed that the presence of HTV and PCLV increased the ability of mosquitoes to transmit DENV and ZIKV to a vertebrate host. By transcriptomic analysis, we found that in DENV-infected mosquitoes, HTV and PCLV block the downregulation of histone H4, which we identify as an important proviral host factor in vivo., (© 2023. The Author(s), under exclusive licence to Springer Nature Limited.)

Yellow fever (YF), caused by the yellow fever virus (YFV), is an emerging viral zoonosis that affects humans and non-human primates (NHP). In South America, YF is naturally maintained through enzootic/sylvatic cycles involving NHPs and mosquitoes (Haemagogus and Sabethes). In this study, we retrospectively analyzed wildlife rodents to better understand their role in a potential alternative YF sylvatic cycle. The plaque reduction neutralization test was performed to detect anti-YFV antibodies, while qPCR targeting the NS5 region of flaviviruses and standard PCR targeting the CprM region were applied to detect YFV RNA in tissue and blood samples. YFV was not evidenced in any of the tested samples. These findings provide additional information regarding sylvatic YFV and emphasize the importance of YFV surveillance in wild animals as potential reservoirs/hosts given the well-established enzootic cycle in the studied areas, mainly in the Atlantic Forest., (© 2022. The Author(s) under exclusive licence to Sociedade Brasileira de Microbiologia.)

Dengue virus (DENV) 1-4 is the etiological agent of dengue, the most important viral infection transmitted by Aedes spp mosquitoes to humans. Our goal was to identify the circulating DENV in Aedes aegypti collected in an area of Brazil where all four DENV serotypes had already been detected in humans, understand the epidemiology better, and to test the vector as a virological surveillance tool. Twenty-eight larvae pools and 174 females of Aedes aegypti were screened by reverse transcriptase quantitative polymerase chain reaction and semi-nested PCR assays. PCR products were sequenced, and phylogenetic analyses were performed. Nine larvae pools (32.1%) were positive for DENV, four (44.4%) with DENV-3, and five (55.6%) with more than one serotype. Fifteen females (8.6%) were positive for any DENV serotype. DENV-1 isolates belong to genotype V, DENV-2 to American-Asian genotype, DENV-3 to genotypes I and III, and DENV-4 to genotypes I and II. We demonstrate for the first time the co-circulation of all four DENV serotypes in larvae pools and adult Aedes aegypti in a hyperendemic area. This scenario represents a challenge for disease control and reinforces the importance of virological surveillance in the vector as a tool for predicting circulating DENV serotypes in humans., (© 2022. EcoHealth Alliance.)

Background: The worldwide epidemics of diseases as dengue and Zika have triggered an intense effort to repurpose drugs and search for novel antivirals to treat patients as no approved drugs for these diseases are currently available. Our aim was to screen plant-derived extracts to identify and isolate compounds with antiviral properties against dengue virus (DENV) and Zika virus (ZIKV)., Methods: Seven thousand plant extracts were screened in vitro for their antiviral properties against DENV-2 and ZIKV by their viral cytopathic effect reduction followed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method, previously validated for this purpose. Selected extracts were submitted to bioactivity-guided fractionation using high- and ultrahigh-pressure liquid chromatography. In parallel, high-resolution mass spectrometric data (MSn) were collected from each fraction, allowing compounds into the active fractions to be tracked in subsequent fractionation procedures. The virucidal activity of extracts and compounds was assessed by using the plaque reduction assay. EC 50 and CC 50 were determined by dose response experiments, and the ratio (EC 50 /CC 50 ) was used as a selectivity index (SI) to measure the antiviral vs. cytotoxic activity. Purified compounds were used in nuclear magnetic resonance spectroscopy to identify their chemical structures. Two compounds were associated in different proportions and submitted to bioassays against both viruses to investigate possible synergy. In silico prediction of the pharmacokinetic and toxicity (ADMET) properties of the antiviral compounds were calculated using the pkCSM platform., Results: We detected antiviral activity against DENV-2 and ZIKV in 21 extracts obtained from 15 plant species. Hippeastrum (Amaryllidaceae) was the most represented genus, affording seven active extracts. Bioactivity-guided fractionation of several extracts led to the purification of lycorine, pretazettine, narciclasine, and narciclasine-4-O-β-D-xylopyranoside (NXP). Another 16 compounds were identified in active fractions. Association of lycorine and pretazettine did not improve their antiviral activity against DENV-2 and neither to ZIKV. ADMET prediction suggested that these four compounds may have a good metabolism and no mutagenic toxicity. Predicted oral absorption, distribution, and excretion parameters of lycorine and pretazettine indicate them as candidates to be tested in animal models., Conclusions: Our results showed that plant extracts, especially those from the Hippeastrum genus, can be a valuable source of antiviral compounds against ZIKV and DENV-2. The majority of compounds identified have never been previously described for their activity against ZIKV and other viruses., (© 2022. The Author(s).)

Equine infectious anemia (EIA) is listed by the World Organization for Animal Health (OIE) as one of the equine diseases that must be notified. No effective treatment or vaccine is available. EIA control is based on segregation and euthanasia of positive equids. The disease is caused by the equine infectious anemia virus (EIAV), a member of the genus Lentivirus of the Retroviridae family. Despite the importance of this disease in equids, EIA has been poorly studied in donkeys (Equus asinus). We evaluate the sanitary conditions related to EIAV in donkeys from a shelter of abandoned animals captured on the roads of the Ceará. A total of 124 donkeys were randomly selected, and three horses lived at the same shelter. The animals were clinically evaluated, and a group of the 20 animals was submitted to hematological tests. Three diagnostic tests for EIA were used, agar gel immunodiffusion (AGID), enzyme-linked immunosorbent assay (ELISA) using EIAV recombinant protein gp90 (rgp90) and recombinant protein p26 (rp26) ELISA, and polymerase chain reaction (PCR) for detection of the EIAV tat-gag gene. From the donkeys, only 1 animal was positive using AGID 0.81% (1/124), compared to 21.8% (27/124) in the rgp90 and 10.5% (13/124) in the rp26 ELISA. Proviral DNA was detected by PCR tat-gag in 8.8% (11/124), and phylogenetic analysis confirms that the EIAV sequences of donkeys from the Brazilian Northeast grouped with Pantanal Brazilian sequences. Thus, in light of the results, we conclude that donkeys are carriers of EIAV and could be sources of infection., (Copyright © 2021. Published by Elsevier Inc.)

Yellow fever virus (YFV) is the causative agent of yellow fever (YF), a hemorrhagic and viscerotropic acute disease. Severe YF has been described in approximately 15-25% of YF patients, with 20-50% of severe YF cases being fatal. Here we analyzed cerebrospinal fluid (CSF) samples collected during the YF outbreak in Brazil in 2018, aiming to investigate CNS neuroinvasion in fatal YFV cases. YFV RNA was screened by RT-qPCR targeting the 3'UTR region of the YFV genome in CSF. CSF samples were tested for the presence of anti-YFV IgM and neutralizing antibodies, coupled with routine laboratory examinations. Among the 13 patients studied, we detected anti-YFV IgM in CSF from eight patients and YFV RNA in CSF from five patients. YFV RNA genomic load in CSF samples ranged from 1.75×103 to 5.42×103 RNA copies/mL. We genotyped YFV from three CSF samples that grouped with other YFV samples from the 2018 outbreak in Brazil within the South-American I genotype. Even though descriptions of neurologic manifestations due to wild type YFV (WT-YFV) infection are rare, since the last YF outbreak in Brazil in 2017-2018, a few studies have demonstrated WT-YFV RNA in CSF samples from YF fatal cases. Serological tests indicated the presence of IgM and neutralizing antibodies against YFV in CSF samples from two patients. Although the presence of viral RNA, IgM and neutralizing antibodies in CSF samples could indicate neuroinvasiveness, further studies are needed to better elucidate the role of YFV neuroinvasion and possible impacts in disease pathogenesis., Competing Interests: Conflict of interests The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

The aetiological agent of equine infectious anaemia (EIA) is the retrovirus equine infectious anemia virus (EIAV) that infects all members of the Equidae family. The EIA is widely disseminated in the Brazilian territory with a high seroprevalence in the Brazilian Pantanal and is mainly diagnosed using agar gel immunodiffusion (AGID). There are few complete EIAV genome sequences available in GenBank, which had an impact on molecular detection studies. In this study, we conducted molecular detection and sequencing of EIAV proviral DNA from Brazilian horses. We analysed the genomic region from exon 1 of tat to gag (tat-gag). Comparative serological tests, comprising AGID and two enzyme-linked immunosorbent assays (ELISAs), were also conducted. Of the 133 samples, 58 were positive in the tat-gag PCR, and 49 nucleotide sequences of 272 bp were obtained. Using this developed tat-gag PCR EIAV proviral DNA was detected in 7% of the AGID-negative samples and 26% of the AGID-negative samples were positive in at least one of the ELISA tests used. Using phylogenetic analysis, the Brazilian Pantanal EIAV sequences grouped in a different clade of EIAV sequences from other countries. Thus, the EIAV sequences can contribute to the knowledge of the tat-gag genomic region in the circulating viruses in the Brazilian Pantanal, in addition to providing new information about the genetic diversity. In addition, the serological results demonstrate the greater sensitivity of the ELISAs used in this study compared to AGID for EIA diagnosis., (© 2020 Wiley-VCH GmbH.)

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has infected millions of people worldwide. SARS-CoV-2 belongs to the Betacoronavirus genus, containing the mouse hepatitis virus (MHV), an extensively studied animal coronavirus. Since MHV and SARS-CoV-2 share the same genus, MHV could offer insights relative to SARS-CoV-2 studies. MHV-3 strain causes hepatitis and cellular injury, making MHV-3 infection one of the best models for this debilitating disease. Surrogate coronaviruses have been used for virus resistance and inactivation studies, and although real-life conditions using SARS-CoV-2 should be encouraged, their use needs to be balanced with safety and costs. MHV can be manipulated under BSL2 laboratory conditions, unlike SARS-CoV-2, making it a model for studying the virucidal effects on coronaviruses. In this study, we used the betacoronavirus MHV-3 as a model to investigate the virucidal activity of an air disinfection equipment named STR Solution®, an air sterilizer with patented technology. MHV-3 was dried on different surfaces and exposed at varying distances from the STR Solution® equipment and at different exposure times. The residual infectivity was evaluated using the endpoint method. There was not a significant reduction (mean p-value = 0.4) of the viral titer under STR Solution® exposition. STR Solution® caused a slight decrease of the infectious particles' titer (> 1 log 10 ) only under the following conditions: polypropylene at 3 m, for 1 and 3 h (1.2 log 10 reduction TCID 50 ) and Sus domesticus skin at 0.05 m, for 1 h (1.3 log 10 reduction TCID50), and at 3 m for 1 h (1.2 log 10 reduction TCID 50 ). These and other studies confirm the usefulness of this model to evaluate virucidal activity., (Copyright © 2021 Elsevier B.V. All rights reserved.)

We evaluated neurologic complications following noncongenital Zika virus infection in 11 children who presented with central nervous system signs. Zika virus RNA was detected by real-time reverse transcription-polymerase chain reaction in cerebrospinal fluid. Approximately one-quarter of patients required antiepileptic medication in follow-up, and 2 children progressed to learning difficulties or developmental delay., (Copyright © 2021. Published by Elsevier Inc.)

Background: Covid-19 has the respiratory tract as the main target of infection, and patients present mainly dyspnea, pneumonia, dry cough, and fever. Nevertheless, organs outside the respiratory tract had been reported in recent studies, including the gastrointestinal tract and liver. The host innate immune system recognizes pathogen-associated molecular patterns (PAMPs) through their pattern recognition receptor (PRRs). Toll-like receptor 7 (TLR-7) is a pattern recognition receptor recognizing ssRNA (SARS-CoV-2 is an ssRNA). Polymorphisms are characterized by two or more alternative forms of a distinct phenotype in the same population. Polymorphisms in tlrs genes can negatively influence the immune response to infectious diseases. There are several references in the literature to non-synonymous single nucleotide (rs) polymorphisms related to several genes. Some of them are important for the innate immunity, as rs 179008 (tlr-7), rs3775291 (tlr3), rs8177374 (tir domain-containing adaptor protein, tirap), rs1024611 (monocyte chemoattractant protein-1, mcp-1) and rs61942233 (2'-5'-oligoadenylate synthase-3, oas-3)., Case Presentation: We identified a 5-year-old-male child with gastrointestinal symptoms and fever presenting acholic stool and jaundice, who was positive for SARS-CoV-2 IgM, IgA, and IgG and presenting the Gln11Leu rs 179008 in tlr-7. The child presented high levels of aspartate aminotransferase, alanine aminotransferase, bilirubin, C-reactive protein, D-dimer, gamma-glutamyl transferase, alkaline phosphatase, and was negative for serological tests for hepatitis A, B, C, E, HIV 1 and 2, herpes virus, cytomegalovirus, Epstein-Barr virus, and negative for RTqPCR for Influenza A and B, RSV and SARS-CoV-2. We also investigated other SNPs in the tlr-3 (rs3775291), tirap (rs8177374), mcp-1 (rs1024611), and oas-3 (rs61942233) genes, and no mutation was detected. After an interview with the child's caregivers, any possible accidental ingestion of drugs or hepatotoxic substances was ruled out., Conclusion: To our knowledge, this is the first report of a SARS-CoV-2 caused hepatitis in a male child that has the tlr-7 Gln11Leu rs 179008, which could impair an efficient initial immune response. The knowledge of the patient's immune deficiency could improve the treatment to correct this deficiency with specific medications., (© 2021. The Author(s).)

The hexane and ethanol extracts from Himatanthus bracteatus (Apocynaceae) stems were evaluated for antiviral activity against Zika virus, yellow fever virus and dengue virus 2 and for cytotoxicity in Vero cells by MTT assay. The ethanol extract showed good antiviral activity against the three viruses with selective indexes (SI) > 10 and its fractionation led to the isolation of the known plumieride that was active only against Zika virus (SI of 15.97).

Dengue virus (DENV) is the most prevalent pathogen of the Flaviviridae family. Due to the considerable increase in DENV incidence and spread, symptoms such as CNS involvement have increased. Heparan sulphate (HS) was the first molecule identified as an adhesion factor for DENV in mammalian cells. Viral phenotypes with different HS interactions are associated with various clinical symptoms, including neurological alterations. Here, using in silico analyses , in vitro studies, and the in vivo mouse model, we characterized two natural circulating DENV3 genotype I (GI) lineage 1 (L1) in Brazil-DENV3 MG-20 (from Minas Gerais) and DENV3 PV&#95;BR (from Rondônia) that present divergent neurovirulent profiles and sensitivity to sulphated molecules. We identified substitutions at the viral envelope (E) in positions 62 and 123 as likely responsible for the differences in neurovirulence. The E62K and E123Q substitutions in DENV3 MG-20 and DENV3 PV&#95;BR, respectively, greatly influenced in silico electrostatic density and heparin docking results. In vivo , mice inoculated with DENV3 MG-20 died, but not those infected with DENV3 PV&#95;BR. The clinical symptoms, such as paralysis of the lower limbs and meningoencephalitis, and histopathology, also differed between the inoculated groups. In vitro heparin and heparinases assays further demonstrated the biological impact of these substitutions. Other characteristics that have been previously associated with alterations in cell tropism and neurovirulence, such as changes in the size of lysis plaques and differences in cytopathic effects in glioblastoma cells, were also observed.

This study aims to characterize the acute neurological manifestations caused by DENV, ZIKV, and YFV during hospitalization; identify the risk factors associated with persistent neurological complications after discharge; and evaluate the time to resolution during clinical follow-up. A prospective study evaluated 505 children, between March 2014 and July 2019, hospitalized with neurological manifestations and that doctors suspected infection of the central nervous system (CNS). Viral infection of collected cerebrospinal fluid (CSF) was confirmed by real-time reverse transcription-polymerase chain reaction (RT-PCR). Patients were clinically followed up after hospital discharge. Analysis of predictive factors and survival curves was performed. This study identified clinical symptoms and changes in the CSF laboratory, electroencephalogram (EEG), and CNS image as predictors of complications in children with confirmed infection in the CNS by DENV, ZIKV, or YFV. No statistical difference was found (p value 0.574) in the time to the resolution of complications in children after hospital discharge between the three types of flaviviruses. Children with YFV, detected in CSF samples, had a 53% higher risk of developing neurological complications. Performing etiological diagnosis by RT-PCR of CSF samples of children with neurological manifestations, especially during Flavivirus outbreaks, is an essential tool for improving the prognosis and clinical follow-up of these patients., (© 2021. Journal of NeuroVirology, Inc.)

Background: Viruses are a common cause of central nervous system (CNS) infections. However, studies of CNS viral pathogens in pediatric patients are poorly explored because viral infections are often erroneously diagnosed as bacterial infections., Methods: 299 CNS samples were collected from pediatric patients aged from one month to 14 years old. A total of 140 viral meningitis cases that met the inclusion criteria were included in this study. In 38 of the 140 cerebral spinal fluid (CSF) samples (27.1%), conventional and real-time PCR were used to identify viruses commonly associated with CNS infections., Results: Among them, 23 patients (16.5%) tested positive for flaviviruses such as dengue, Zika, and yellow fever virus, eight patients (5.7%) were positive for enterovirus (ENTV), and six patients (4.3%) were positive for human herpesvirus 1/2. We also identified one case of dengue virus and ENTV co-infection., Conclusions: A correlation between clinical symptoms and laboratory findings for the viruses was identified. Our study also reinforces the importance of including viruses in the laboratory diagnosis of CNS infections especially flaviviruses, which assists public health authorities in implementing early interventions., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Bovine vaccinia (BV), caused by Vaccinia virus (VACV), is a zoonotic disease characterized by exanthematous lesions on the teats of dairy cows and the hands of milkers, and is an important public health issue in Brazil and South America. BV also results in economic losses to the dairy industry, being a burden to the regions involved in milk production. In the past 20 years, much effort has been made to increase the knowledge regarding BV epidemiology, etiologic agents, and interactions with the hosts and the environment. In the present study, we evaluated milking practices that could be associated with VACV infections in an endemic area in Brazil and proposed an educational tool to help prevent VACV infections. In our survey, 124 individuals (51.7%) from a total of 240 had previously heard of BV, 94 of which knew about it through BV outbreaks. Although most individuals involved in dairy activities ( n = 85/91) reported having good hygiene practices, only 29.7% used adequate disinfecting products to clean their hands and 39.5% disinfected cows' teats before and after milking. Furthermore, 46.7% of individuals reported having contact with other farm and domestic animals besides dairy cattle. We also evaluated the presence of IgG and IgM antibodies in the surveyed population. Overall, 6.1% of likely unvaccinated individuals were positive for anti- Orthopoxvirus IgG antibodies, and 1.7% of all individuals were positive for IgM antibodies. Based on our findings, we proposed educational materials which target individuals with permanent residence in rural areas (mainly farmers and milkers), providing an overview and basic information about preventive measures against VACV infections that could enhance BV control and prevention efforts, especially for vulnerable populations located in endemic areas.

The Zika virus (ZIKV) epidemic in Brazil occurred in regions where dengue viruses (DENV) are historically endemic. We investigated the differences in adverse pregnancy/infant outcomes in two cohorts comprising 114 pregnant women with PCR-confirmed ZIKV infection in Rio de Janeiro, Southeastern Brazil ( n = 50) and Manaus, in the north region of the country ( n = 64). Prior exposure to DENV was evaluated through plaque reduction neutralizing antibody assays (PRNT 80) and DENV IgG serologies. Potential associations between pregnancy outcomes and Zika attack rates in the two cities were explored. Overall, 31 women (27%) had adverse pregnancy/infant outcomes, 27 in Rio (54%) and 4 in Manaus (6%), p < 0.001. This included 4 pregnancy losses (13%) and 27 infants with abnormalities at birth (24%). A total of 93 women (82%) had evidence of prior DENV exposure, 45 in Rio (90%) and 48 in Manaus (75%). Zika attack rates differed; the rate in Rio was 10.28 cases/10,000 and in Manaus, 0.6 cases/10,000, p < 0.001. Only Zika attack rates (Odds Ratio: 17.6, 95% Confidence Interval 5.6-55.9, p < 0.001) and infection in the first trimester of pregnancy (OR: 4.26, 95% CI 1.4-12.9, p = 0.011) were associated with adverse pregnancy and infant outcomes. Pre-existing immunity to DENV was not associated with outcomes (normal or abnormal) in patients with ZIKV infection during pregnancy.

The world is experiencing the worst global health crisis in recent decades since December/2019 due to a new pandemic coronavirus. The COVID-19 disease, caused by SARS-CoV-2, has resulted in more than 30 million cases and 950 thousand deaths worldwide as of September 21, 2020. Determining the extent of the virus on public surfaces is critical for understanding the potential risk of infection in these areas. In this study, we investigated the presence of SARS-CoV-2 RNA on public surfaces in a densely populated urban area in Brazil. Forty-nine of 933 samples tested positive (5.25%) for SARS-CoV-2 RNA, including samples collected from distinct material surfaces, including metal and concrete, and distinct places, mainly around hospital care units and public squares. Our data indicated the contamination of public surfaces by SARS-CoV-2, suggesting the circulation of infected patients and the risk of infection for the population. Constant monitoring of the virus in urban areas is required as a strategy to fight the pandemic and prevent further infections., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

The global emergence of zoonotic viruses, including poxviruses, poses one of the greatest threats to human and animal health. Forty years after the eradication of smallpox, emerging zoonotic orthopoxviruses, such as monkeypox, cowpox, and vaccinia viruses continue to infect humans as well as wild and domestic animals. Currently, the geographical distribution of poxviruses in a broad range of hosts worldwide raises concerns regarding the possibility of outbreaks or viral dissemination to new geographical regions. Here, we review the global host ranges and current epidemiological understanding of zoonotic orthopoxviruses while focusing on orthopoxviruses with epidemic potential, including monkeypox, cowpox, and vaccinia viruses.

The earliest possible diagnosis and understanding of the infection mechanisms play a crucial role in the outcome of fighting viral diseases. Thus, we designed and developed for the first time, novel bioconjugates made of Ag-In-S@ZnS (ZAIS) fluorescent quantum dots coupled with ZIKA virus via covalent amide bond with carboxymethylcellulose (CMC) biopolymer for labeling and bioimaging the virus-host cell interactions mechanisms through confocal laser scanning microscopy. This work offers relevant insights regarding the profile of the ZIKA virus-nanoparticle conjugates interactions with VERO cells, which can be applied as a nanoplatform to elucidate the infection mechanisms caused by this viral disease., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2020 Elsevier B.V. All rights reserved.)

Background: From the end of 2016 until the beginning of 2019, Brazil faced a massive sylvatic yellow fever (YF) outbreak. The 2016-2019 YF epidemics affected densely populated areas, especially the Southeast region, causing thousands of deaths of humans and non-human primates (NHP)., Methodology/principal Findings: We conducted a molecular investigation of yellow fever virus (YFV) RNA in 781 NHP carcasses collected in the urban, urban-rural interface, and rural areas of Minas Gerais state, from January 2017 to December 2018. Samples were analyzed according to the period of sampling, NHP genera, sampling areas, and sampling areas/NHP genera to compare the proportions of YFV-positive carcasses and the estimated YFV genomic loads. YFV infection was confirmed in 38.1% of NHP carcasses (including specimens of the genera Alouatta, Callicebus, Callithrix, and Sapajus), from the urban, urban-rural interface, and rural areas. YFV RNA detection was positively associated with epidemic periods (especially from December to March) and the rural environment. Higher median viral genomic loads (one million times) were estimated in carcasses collected in rural areas compared to urban ones., Conclusions/significance: The results showed the wide occurrence of YF in Minas Gerais in epidemic and non-epidemic periods. According to the sylvatic pattern of YF, a gradient of viral dissemination from rural towards urban areas was observed. A high YF positivity was observed for NHP carcasses collected in urban areas with a widespread occurrence in 67 municipalities of Minas Gerais, including large urban centers. Although there was no documented case of urban/Aedes YFV transmission to humans in Brazil during the 2016-2019 outbreaks, YFV-infected NHP in urban areas with high infestation by Aedes aegypti poses risks for YFV urban/Aedes transmission and urbanization., Competing Interests: The authors have declared that no competing interests exist.

Herpes simplex virus type 1 (HSV-1) is the main etiological agent of acute and sporadic encephalitis. Proteins of the suppressor of cytokine signaling (SOCS) family have shown to regulate the inflammation during HSV-1 infection in the brain. However, the effects of SOCS2 and SOCS3 in viral encephalitis remain unclear. The aim of the current study is to investigate the potential association between SOCS2, SOCS3, cytokines, and hippocampal damage, especially neuronal apoptosis, during acute intracranial HSV-1 infection in mice. Male C57BL/6 mice were infected by intracranial route with 10 2 plaque-forming units (PFU) inoculum of purified HSV-1. At three days post-infection (3 d.p.i.), mice were euthanized and their hippocampi were collected for histopathological analysis, immunohistochemical reaction against active caspase-3 and quantification of SOCS2, SOCS3 and cytokines (tumoral necrosis factor (TNF), interleukin (IL) 1β, IL-6, IL-10; interferon (IFN) -α, IFN-β, IFN-γ) mRNA expression. Infected mice exhibited neuronal loss and hemorrhagic focus in Cornu Ammonis (CA) region. The apoptotic index was higher in infected mice compared to controls. HSV-1 infection was associated with increased hippocampal expression of TNF, IL1-β, IL-6 and IFNα/IFNβ and decreased expression of IL-10, IFN-γ, SOCS2 and SOCS3. Our results suggest that down regulation of SOCS2 and SOCS3 contributes to a pro-inflammatory environment associated with hippocampal damage and neuronal apoptosis during acute HSV-1 infection in mice., (Copyright © 2020 Elsevier B.V. All rights reserved.)

We evaluated 345 wild animals from southern and south-eastern Brazil to understand their role in vaccinia virus (VACV) transmission cycle. VACV DNA was detected in rodents, marsupials, chiroptera and cingulate, expanding the knowledge of VACV host range in wildlife that could potentially act as source of infection in rural and urban areas., (© 2020 Blackwell Verlag GmbH.)

The aim of this study was to evaluate the possibility of free-ranging animals/hunting dogs as sources of infection in the vaccinia virus (VACV) transmission chain. Serological, cell culture and molecular assays were conducted in 56 free-ranging animals and 22 hunting dogs. ELISA/neutralizing assays showed that two (2.5%) capybaras (Hydrochoerus hydrochaeris) had anti-OPV positive antibodies, while all samples tested negative through PCR/cell culture. After being hit by cars on roads, capybaras that exhibited neither clinical signs nor any association with bovine outbreaks had neutralizing antibodies against the Orthopoxvirus, as detected through plaque-reduction neutralizing tests and ELISA. Evidence exists regarding peridomestic capybaras acting as a source of the virus and serving as a link between wild and urban environments, thus contributing to viral maintenance., (© 2019 Blackwell Verlag GmbH.)