Circulation of Chikungunya virus East-Central-South Africa genotype during an outbreak in 2016-17 in Piaui State, Northeast Brazil

Chikungunya virus (CHIKV) is an arbovirus that emerged in the Americas in 2013. Infection with CHIKV is symptomatic in most of the cases and patients can develop chronic arthralgia that lasts from months to years in over 40% of the cases. The East-Central-South Africa (ECSA) genotype was introduced in Brazil in 2014, in Bahia State. Here we report the circulation of the CHIKV ECSA genotype in Piaui State, Northeast Brazil, during the years 2016-2017. The phylogenetic analysis revealed a single introduction of this lineage probably in 2015 and its maintenance at least until 2017. This analysis has also demonstrated the proximity of this genotype with isolates from neighboring States, and its partial nucleotide sequence of the viral E1 gene revealed a synapomorphy synonyms. This finding highlights the spread of the ECSA genotype in Brazil and supports its circulation in the Brazilian Northeast

Prospecção de coronavírus humano e vírus da raiva em pequenos mamíferos silvestres, no estado de Minas Gerais, Brasil

The emergence of viruses is an important public health problem worldwide. Some animals, including wild mammals, play an important role in the maintenance and transmission of viruses and can act as hosts and natural reservoirs. Coronaviruses (CoVs) and rabies virus (RABV) belong to Coronaviridae, and Rhabdoviridae families, respectively. Viruses belonging to these two families have been isolated from wild and domestic animals. Coronaviruses are viruses that cause respiratory, enteric, hepatic and neurological disorders and are widely spread among humans and other mammals. Rabies virus causes progressive acute encephalitis in many mammals, including humans. In this context, the aim of this work was to perform a prospective study of human coronavirus and rabies virus in small wild mammals in the state of Minas Gerais, Brazil. Small wild mammals were collected between the years 2012 and 2013. Rodents and marsupials came from the Campus Rio Pomba of Instituto Federal de Educação, Ciência e Tecnologia do Sudeste de Minas Gerais and bats from Parque Estadual da Serra do Papagaio and Jardim Botânico da Universidade Federal de Juiz de Fora. Samples of liver, lung, kidney, and serum from these animals were subjected to RNA extraction and cDNA synthesis. The real-time PCR (qPCR) was performed for human coronavirus investigation using cDNA obtained from 58 lung samples, 54 liver samples, 120 serum samples, and 18 kidney samples, For the investigation of rabies virus, qPCR was performed with cDNA derived from 58 lung samples, 120 serum samples, and 18 kidneys samples. In this study, 17 samples were positive (6,8%), out of 250 tested for human coronavirus HKU1, from twelve rodents (9,23%) and three bats (16,66%). None of the 196 samples tested were positive for RABV in qPCR. These results demonstrate for the first time, the circulation of HCoV-HKU1 in rodents and bats, such animals may be developing a role in the maintenance and emergence of these viruses in the state of Minas Gerais. In addition, it emphasizes the importance of animal species surveillance studies to understand the circulation, maintenance, and transmission of these viruses and their emerging potential.A emergência de viroses é um importante problema de saúde pública mundial. Alguns animais, incluindo mamíferos silvestres, têm um importante papel na manutenção e na transmissão de vírus, podendo agir como hospedeiros e reservatórios naturais. Os coronavírus (CoVs) e o vírus da raiva (RABV) pertencem às famílias Coronaviridae e Rhabdoviridae respectivamente. Esses vírus, pertencentes a essas duas famílias, têm sido isolados a partir de animais silvestres e domésticos. Os coronavírus são vírus que causam doenças respiratórias, entéricas, hepáticas e neurológicas e estão amplamente distribuídos entre os humanos e outros mamíferos. O vírus da raiva causa encefalite aguda progressiva em diversos mamíferos, incluindo também humanos. Diante desse contexto, este trabalho teve como objetivo a prospecção de coronavírus humano e do vírus da raiva em pequenos mamíferos silvestres no estado de Minas Gerais, Brasil. Os pequenos mamíferos silvestres dos quais foram investigados os vírus de interesse deste estudo, procederam de três diferentes áreas de estudo, onde foram coletados entre os anos de 2012 e 2013. Roedores e marsupiais, foram provenientes do Campus Rio Pomba do Instituto Federal de Educação, Ciência e Tecnologia do Sudeste de Minas Gerais e os morcegos do Parque Estadual da Serra do Papagaio e do Jardim Botânico da Universidade Federal de Juiz de Fora. Amostras de fígado, pulmão, soro e rins oriundos desses animais foram submetidas a extração de RNA total, seguida da síntese de cDNA. Foi realizado o PCR em tempo real (qPCR) com as 58 amostras de pulmão, 54 amostras de fígado, 120 amostras de soro e 18 amostras de rim, para a investigação de coronavírus humano. Para a investigação do vírus da raiva, foi realizado o qPCR com 58 amostras de pulmão, 120 amostras de soro e 18 amostras de rins. Neste estudo, foram detectadas 17 (6,8%) amostras positivas, de 250 testadas, para o coronavírus humano HKU1, provenientes de doze roedores (9,23%) e três morcegos (16,66%). Nenhuma das 196 amostras testadas para RABV foram positivas no qPCR. Esses resultados apontam, pela primeira vez, a circulação de HCoV-HKU1 em roedores e morcegos, podendo esses animais estarem desenvolvendo um papel na manutenção e emergência desses vírus no estado de Minas Gerais. Além disso, enfatiza a importância de estudos de vigilância de espécies animais, para compreender a circulação, manutenção e transmissão desses vírus, bem como o seu potencial emergente.CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superio

Spatial epidemiology of yellow fever: Identification of determinants of the 2016-2018 epidemics and at-risk areas in Brazil.

Optimise control strategies of infectious diseases, identify factors that favour the circulation of pathogens, and propose risk maps are crucial challenges for global health. Ecological niche modelling, once relying on an adequate framework and environmental descriptors can be a helpful tool for such purposes. Despite the existence of a vaccine, yellow fever (YF) is still a public health issue. Brazil faced massive sylvatic YF outbreaks from the end of 2016 up to mid-2018, but cases in human and non-human primates have been recorded until the beginning of 2020. Here we used both human and monkey confirmed YF cases from two epidemic periods (2016/2017 and 2017/2018) to describe the spatial distribution of the cases and explore how biotic and abiotic factors drive their occurrence. The distribution of YF cases largely overlaps for humans and monkeys, and a contraction of the spatial extent associated with a southward displacement is observed during the second period of the epidemics. More contributive variables to the spatiotemporal heterogeneity of cases were related to biotic factors (mammal richness), abiotic factors (temperature and precipitation), and some human-related variables (population density, human footprint, and human vaccination coverage). Both projections of the most favourable conditions showed similar trends with a contraction of the more at-risk areas. Once extrapolated at a large scale, the Amazon basin remains at lower risk, although surrounding forest regions and notably the North-West region, would face a higher risk. Spatial projections of infectious diseases often relied on climatic variables only; here for both models, we instead highlighted the importance of considering local biotic conditions, hosts vulnerability, social and epidemiological factors to run the spatial risk analysis correctly: all YF cases occurring later on, in 2019 and 2020, were observed in the predicted at-risk areas

Screening for Zika virus RNA in sera of suspected cases: a retrospective cross-sectional study

Abstract Background Zika virus (ZIKV) became a global human health concern owing to its rapid spread worldwide and its association with congenital and neurological disorders. The current epidemiological profile of arboviruses in Brazil is characterized by widespread co-circulation of Dengue virus, Chikungunya virus, and ZIKV throughout the country. These viruses cause acute diseases frequently with overlapping symptoms, which could result in an inaccurate diagnosis based solely on clinical and epidemiological grounds. Here we conducted a screening for ZIKV RNA in serum samples from patients across Brazil with suspected ZIKV infection. Methods Using RT-qPCR, we investigated ZIKV RNA in 3001 serum samples. Samples were passively acquired through a private laboratory network, between December 2015 and August 2016, from 27 Brazilian Federative Units. We performed descriptive statistics on demographic variables including sex, age, and geographic location. Results ZIKV was detected in 11.4% (95%CI = 10.3–12.6%) of the sera. ZIKV RNA was detected in sera collected throughout the country, but during the analyzed period, RNA was more frequently detected in samples from the Southeast, Midwest, and North regions (3.9 to 5.8 times higher) when compared to the Northeast and South regions. Conclusions These data reinforce the importance of laboratory diagnosis, surveillance systems, and further epidemiological studies to understand the dynamics of outbreaks and diseases associated with ZIKV and other arboviruses

Exploring Quercetin Hydrate’s Potential as an Antiviral Treatment for Oropouche Virus

The Oropouche virus is an orthobunyavirus responsible for causing Oropouche fever, a disease that primarily affects thousands of people in South and Central America. Currently, no specific antiviral treatments or vaccines are available against this virus, highlighting the urgent need for safe, affordable, and effective therapies. Natural products serve as an important source of bioactive compounds, and there is growing interest in identifying natural bioactive molecules that could be used for treating viral diseases. Quercetin hydrate is a compound classified as a flavonoid, which has garnered scientific attention due to its potential health benefits and its presence in various plant-based foods. In this study, we aim to evaluate the in vitro antiviral activity of quercetin hydrate against the Oropouche virus (OROV). Furthermore, we intend to explore its mode of action through in silico approaches. The cytotoxicity and antiviral activity of the compound were assessed using Vero cells. In addition, in silico studies were also performed through molecular docking, molecular dynamics simulations, Molecular Mechanics Poisson–Boltzmann surface area (MM/PBSA), and quantum-mechanical analysis in order to evaluate the interaction with the Gc protein of OROV. The assay revealed that the compound was highly active against the virus, inhibiting OROV with an EC50 value of 53.5 ± 26.5 µM under post-infection treatment conditions. The present study demonstrates that the compound is a promising antiviral agent; however, the mechanisms of action proposed in this study need to be experimentally verified by future assays

Antiviral Activity of Quercetin Hydrate against Zika Virus

Zika virus (ZIKV) has re-emerged in recent decades, leading to outbreaks of Zika fever in Africa, Asia, and Central and South America. Despite its drastic re-emergence and clinical impact, no vaccines or antiviral compounds are available to prevent or control ZIKV infection. This study evaluated the potential antiviral activity of quercetin hydrate against ZIKV infection and demonstrated that this substance inhibits virus particle production in A549 and Vero cells under different treatment conditions. In vitro antiviral activity was long-lasting (still observed 72 h post-infection), suggesting that quercetin hydrate affects multiple rounds of ZIKV replication. Molecular docking indicates that quercetin hydrate can efficiently interact with the specific allosteric binding site cavity of the NS2B-NS3 proteases and NS1-dimer. These results identify quercetin as a potential compound to combat ZIKV infection in vitro

Detection of Zika Virus in <i>Aedes aegypti</i> and <i>Aedes albopictus</i> Mosquitoes Collected in Urban Forest Fragments in the Brazilian Amazon

Zika virus (ZIKV) is an RNA flavivirus (Flaviviridae family) endemic in tropical and subtropical regions that is transmitted to humans by Aedes (Stegomyia) species mosquitoes. The two main urban vectors of ZIKV are Aedes aegypti and Aedes albopictus, which can be found throughout Brazil. This study investigated ZIKV infection in mosquito species sampled from urban forest fragments in Manaus (Brazilian Amazon). A total of 905 non-engorged female Ae. aegypti (22 specimens) and Ae. albopictus (883 specimens) were collected using BG-Sentinel traps, entomological hand nets, and Prokopack aspirators during the rainy and dry seasons between 2018 and 2021. All pools were macerated and used to inoculate C6/36 culture cells. Overall, 3/20 (15%) Ae. aegypti and 5/241 (2%) Ae. albopictus pools screened using RT-qPCR were positive for ZIKV. No supernatants from Ae. aegypti were positive for ZIKV (0%), and 15 out of 241 (6.2%) Ae. albopictus pools were positive. In this study, we provide the first-ever evidence of Ae. albopictus naturally infected with ZIKV in the Amazon region

Neighbor danger: Yellow fever virus epizootics in urban and urban-rural transition areas of Minas Gerais state, during 2017-2018 yellow fever outbreaks in Brazil.

BackgroundFrom 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 findingsWe 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/significanceThe 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

Caffeic Acid Has Antiviral Activity against Ilhéus Virus In Vitro

Ilhéus virus (ILHV) is a neglected mosquito-borne flavivirus. ILHV infection may lead to Ilhéus fever, an emerging febrile disease like dengue fever with the potential to evolve into a severe neurological disease characterized by meningoencephalitis; no specific treatments are available for this disease. This study assessed the antiviral properties of caffeic acid, an abundant component of plant-based food products that is also compatible with the socioeconomic limitations associated with this neglected infectious disease. The in vitro activity of caffeic acid on ILHV replication was investigated in Vero and A549 cell lines using plaque assays, quantitative RT-PCR, and immunofluorescence assays. We observed that 500 µM caffeic acid was virucidal against ILHV. Molecular docking indicated that caffeic acid might interact with an allosteric binding site on the envelope protein

Caffeic Acid Has Antiviral Activity against Ilh&eacute;us Virus In Vitro

Ilh&eacute;us virus (ILHV) is a neglected mosquito-borne flavivirus. ILHV infection may lead to Ilh&eacute;us fever, an emerging febrile disease like dengue fever with the potential to evolve into a severe neurological disease characterized by meningoencephalitis; no specific treatments are available for this disease. This study assessed the antiviral properties of caffeic acid, an abundant component of plant-based food products that is also compatible with the socioeconomic limitations associated with this neglected infectious disease. The in vitro activity of caffeic acid on ILHV replication was investigated in Vero and A549 cell lines using plaque assays, quantitative RT-PCR, and immunofluorescence assays. We observed that 500 &micro;M caffeic acid was virucidal against ILHV. Molecular docking indicated that caffeic acid might interact with an allosteric binding site on the envelope protein