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BACKGROUND: Chikungunya is a mosquito-borne virus that has been causing large outbreaks in the Americas since 2014. In Brazil, Asian-Caribbean (AC) and East-Central-South-African (ECSA) genotypes have been detected and lead to large outbreaks in several Brazilian states. In Rio Grande do Sul (RS), the southernmost state of Brazil, the first cases were reported in 2016. OBJECTIVES AND METHODS: We employed genome sequencing and epidemiological investigation to characterise the Chikungunya fever (CHIKF) burden in RS between 2017-2021. FINDINGS: We detected an increasing CHIKF burden linked to travel associated introductions and communitary transmission of distinct lineages of the ECSA genotype during this period. MAIN CONCLUSIONS: Until 2020, CHIKV introductions were most travel associated and transmission was limited. Then, in 2021, the largest outbreak occurred in the state associated with the introduction of a new ECSA lineage. CHIKV outbreaks are likely to occur in the near future due to abundant competent vectors and a susceptible population, exposing more than 11 million inhabitants to an increasing infection risk.
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Febre de Chikungunya , Vírus Chikungunya , Animais , Humanos , Vírus Chikungunya/genética , Brasil/epidemiologia , Viagem , Filogenia , Mosquitos Vetores , Surtos de Doenças , GenótipoRESUMO
BACKGROUND: In Brazil, the yellow fever virus (YFV) is maintained in a sylvatic cycle involving wild mosquitoes and non-human primates (NHPs). The virus is endemic to the Amazon region; however, waves of epidemic expansion reaching other Brazilian states sporadically occur, eventually causing spillovers to humans. OBJECTIVES: To report a surveillance effort that led to the first confirmation of YFV in NHPs in the state of Minas Gerais (MG), Southeast region, in 2021. METHODS: A surveillance network was created, encompassing the technology of smartphone applications and coordinated actions of several research institutions and health services to monitor and investigate NHP epizootics. FINDINGS: When alerts were spread through the network, samples from NHPs were collected and YFV infection confirmed by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and genome sequencing at an interval of only 10 days. Near-complete genomes were generated using the Nanopore MinION sequencer. Phylogenetic analysis indicated that viral genomes were related to the South American genotype I, clustering with a genome detected in the Amazon region (state of Pará) in 2017, named YFVPA/MG sub-lineage. Fast YFV confirmation potentialised vaccination campaigns. MAIN CONCLUSIONS: A new YFV introduction was detected in MG 6 years after the beginning of the major outbreak reported in the state (2015-2018). The YFV strain was not related to the sub-lineages previously reported in MG. No human cases have been reported, suggesting the importance of coordinated surveillance of NHPs using available technologies and supporting laboratories to ensure a quick response and implementation of contingency measures to avoid YFV spillover to humans.
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Vírus da Febre Amarela , Vírus da Febre Amarela/genética , Filogenia , Brasil/epidemiologiaRESUMO
Bats play a significant role in maintaining their ecosystems through pollination, dispersal of seeds, and control of insect populations, but they are also known to host many microorganisms and have been described as natural reservoirs for viruses with zoonotic potential. The diversity of viruses in these animals remains largely unknown, however, because studies are limited by species, location, virus target, or sample type. Therefore, the aim of this study was to detect fragments of viral genomes in bat samples. We performed high-throughput sequencing analysis and specific PCR and RT-PCR on pools of anal and oropharyngeal swabs from Artibeus lituratus and Sturnira lilium collected in southern Brazil. As a result, a member of the family Adenoviridae related to human adenovirus C was detected in anal swabs from S. lilium. In addition, we detected a papillomavirus in an anal swab from A. lituratus. Our analyses also allowed the detection of adenoviruses and parvoviruses in oropharyngeal swabs collected from A. lituratus. These results increase our knowledge about viral diversity and illustrate the importance of conducting virus surveillance in bats.
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Infecções por Adenoviridae/veterinária , Adenoviridae/isolamento & purificação , Quirópteros/virologia , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/veterinária , Infecções por Parvoviridae/veterinária , Parvovirus/isolamento & purificação , Adenoviridae/classificação , Adenoviridae/genética , Infecções por Adenoviridae/virologia , Animais , Brasil , Genoma Viral , Humanos , Papillomaviridae/classificação , Papillomaviridae/genética , Infecções por Papillomavirus/virologia , Infecções por Parvoviridae/virologia , Parvovirus/classificação , Parvovirus/genética , FilogeniaRESUMO
Since starts the coronavirus disease 2019 (COVID-19) pandemic identified the presence of genomic fragments of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in various environmental matrices: domestic sewage, surface waters, and contaminated freshwater. Environmental monitoring of SARS-CoV-2 is a tool for evaluating trend curves over the months, compared to several clinical cases of the disease. The objective of this study was to monitor the SARS-CoV-2 in environmental samples collected in different sites in a metropolitan area of Porto Alegre, Southern Brazil. During 10 months from 2020 to 2021, 300 samples were collected weekly and biweekly from nine points located in 3 cities: one point from a wastewater treatment plant (WWTP) in São Leopoldo (fortnightly collection), two points in Dilúvio Stream in Porto Alegre (fortnightly collection), two points in Pampa and Luiz Rau Streams (weekly collection), and two points in public fountains (fortnightly collection) in Novo Hamburgo. After collection, samples were concentrated by ultracentrifugation, and viral nucleic acids were extracted using MagMax® Core Nucleic Acid Purifications kits and submitted to RT-qPCR, using E, N1, and N2 gene targets of SARS-CoV-2. Only 7% (3/41) samples from public fountains were positive, with a mean viral load (VL) of SARS-CoV-2 RNA of 5.02 × 101 gc/l (2.41~8.59 × 101 gc/l), while the streams had average VL of 7.43 × 105 gc/l (Pampa), 7.06 × 105 gc/l (Luiz Rau), 2.01 × 105 gc/l (Dilúvio), and 4.46 × 105 cg/l (WWTP). The results showed varying levels of viral presence in different sample types, with a demonstrated correlation between environmental viral load and clinical COVID-19 cases. These findings contribute to understanding virus persistence and transmission pathways in the environment. Continuous monitoring, especially in less developed regions, is crucial for early detection of vaccine resistance, new variants, and potential COVID-19 resurgence.
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COVID-19 , SARS-CoV-2 , Humanos , RNA Viral , Brasil/epidemiologia , Monitoramento AmbientalRESUMO
Despite the considerable morbidity and mortality of yellow fever virus (YFV) infections in Brazil, our understanding of disease outbreaks is hampered by limited viral genomic data. Here, through a combination of phylogenetic and epidemiological models, we reconstructed the recent transmission history of YFV within different epidemic seasons in Brazil. A suitability index based on the highly domesticated Aedes aegypti was able to capture the seasonality of reported human infections. Spatial modeling revealed spatial hotspots with both past reporting and low vaccination coverage, which coincided with many of the largest urban centers in the Southeast. Phylodynamic analysis unraveled the circulation of three distinct lineages and provided proof of the directionality of a known spatial corridor that connects the endemic North with the extra-Amazonian basin. This study illustrates that genomics linked with eco-epidemiology can provide new insights into the landscape of YFV transmission, augmenting traditional approaches to infectious disease surveillance and control.
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Febre Amarela , Vírus da Febre Amarela , Humanos , Vírus da Febre Amarela/genética , Filogenia , Brasil/epidemiologia , Febre Amarela/epidemiologia , Surtos de Doenças , GenômicaRESUMO
Post-exposure prophylaxis (PEP) is necessary to prevent the fatal onset of rabies but requires optimization to avoid overuse in populations at risk of rabies. In Brazil, the incidence of dog bites remains high, with almost half of dog-bite patients not receiving the PEP recommended by the Ministry of Health guidelines between 2008 and 2017. In this study, we aimed to identify the factors that limit the appropriate prescribing of PEP by interviewing health professionals responsible for PEP administration and completion of the 'Information System on Diseases of Compulsory Declaration' (SINAN) form reporting human anti-rabies care for patients seeking health care after a dog bite. We conducted 147 questionnaires (45 questions each) in three Brazilian states (i.e., Rio Grande do Sul, Santa Catarina, Rio Grande do Norte) including questions related to the criteria used by professionals to classify a dog as "suspect" or "rabid", knowledge on PEP prescription guidelines, SINAN and communication with veterinarians. Our analyses showed that most health professionals delivering PEP in these three states struggle to identify a rabies "suspect" dog according to the Ministry of Health guidelines, and to indicate the adequate PEP regimen, with only 11% of professionals prescribing the appropriate PEP under various dog-bite patient scenarios. PEP knowledge score was higher among professionals trained on PEP guidelines and working in facilities with the highest incidence of dog bites. In contrast, PEP knowledge scores did not vary significantly between states, and were not correlated to the professional's level of experience, the number of colleagues available at the health unit or the professional's confidence on prescribing appropriate PEP. Our results suggest that knowledge gaps in PEP administration among health professionals of Brazil can be reduced by implementing training programs to differentiate among rabies risk scenarios, prescribe the corresponding appropriate PEP and improve communication between health and veterinary authorities.
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Leptospirosis is an infectious disease caused by Leptospira spp. and affects animals and humans. Reports of leptospirosis in bats have increased and prompted epidemiological research in Brazil. This study aimed to perform a molecular and epidemiological investigation of pathogenic Leptospira spp. in bat kidneys. The total DNA was extracted from 102 kidney samples from chiropterous of different species and cities in Rio Grande do Sul State (RS), Brazil. The polymerase chain reaction was used to amplify a fragment corresponding to lipL32 gene, which is only present in pathogenic Leptospira spp. lipL32 gene was detected in 22.5% (23/102) of the bat kidney tissues. Phylogenetic analysis showed that L. interrogans is circulating in bats in RS. Most species of the bats collected were insectivores. Pathogenic Leptospira spp. detection in bats demonstrated that these animals participate in the infection chain of leptospirosis and, therefore, may play as reservoirs and disseminators of this microorganism. Thus, it is important to monitor infectious agents, especially with zoonotic potential in bats.
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Quirópteros , Leptospira interrogans , Leptospira , Leptospirose , Animais , Humanos , Quirópteros/microbiologia , Filogenia , Leptospira interrogans/genética , Brasil/epidemiologia , Leptospira/genética , Leptospirose/epidemiologia , Leptospirose/veterinária , Leptospirose/microbiologiaRESUMO
Rabies is an encephalitis caused by rabies virus, whose transmission occurs upon contact with infected animals' saliva. The diagnosis is usually performed post-mortem through a direct fluorescent antibody test (DFAT). If the DFAT results are negative, they must be confirmed with an isolation test, usually the mouse inoculation test (MIT), which implies the suffering and death of the animals, high costs and most importantly, up to 28 days to confirm a negative result. Another issue related to rabies diagnosis is the sample collection and storage, which is critical for the rabies virus' RNA genome. Thus, this study aimed to evaluate (i) reverse transcriptase polymerase chain reaction (RT-PCR) and Rabies Tissue Culture Infection Tests (RTCIT) in comparison to DFAT and MIT and (ii) FTA® cards as an alternative sample collection and preservation method. Eighty animal samples were evaluated through DFAT, RTCIT and RT-PCR; MIT was performed only in DFAT-negative samples. FTA® cards were evaluated with a subset of 64 samples, with sufficient material for imprinting. Sensitivity, specificity, positive (PPV) and negative predictive values (NPV), agreement and Cohen's kappa were calculated for each test combination. RTCIT had higher sensitivity (92.5%) and RT-PCR had higher specificity (92.3%) compared to DFAT. The combination of tests enhanced sensitivity, NPV and Cohen's kappa (considering positive results by RTCIT or RT-PCR), and specificity and PPV (when both tests were concordant). The PCR based on FTA® cards as sample source was specific (84.6%-96.2%) but presented lower sensitivity (29.7%-73.0%), although it could detect as positive four DFAT-negative samples. RTCIT and RT-PCR may be used as confirmatory tests in DFAT-negative samples. Moreover, FTA® cards may be helpful for sample collection in field situations where a long time is needed until the sample undergoes laboratory testing.
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Vírus da Raiva , Raiva , Doenças dos Roedores , Animais , Camundongos , Raiva/diagnóstico , Raiva/veterinária , Reação em Cadeia da Polimerase/veterinária , Manejo de Espécimes/veterinária , RNA Viral/análise , Sensibilidade e Especificidade , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterináriaRESUMO
Wastewater-based epidemiology (WBE) may be successfully used to comprehensively monitor and determine the scale and dynamics of some infections in the community. We monitored severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA in raw wastewater samples from Porto Alegre, Southern Brazil. The samples were collected and analyzed every week between May 2020 to May 2021. Meanwhile, different social restrictions were applied according to the number of hospitalized patients in the region. Weekly samples were obtained from two wastewater treatment plants (WWTP), named Navegantes and Serraria. To determine the SARS-CoV-2 RNA titers in wastewater, we performed RT-qPCR analysis targeting the N gene (N1). The highest titer of SARS-CoV-2 RNA was observed between epidemiological weeks (EWs) 33-37 (August), 42-43 (October), 45-46 (November), 49-51 (December) in 2020, and 1-3 (January), 7-13 (February to March) in 2021, with viral loads ranging from 1 × 106-3 × 106 genomic copies/Liter. An increase in positive confirmed cases followed such high viral loads. Depending on the sampling method used, positive cases increased in 6-7 days and 15 days after the rise of viral RNA titers in wastewater, with composite sampling methods showing a lower time lag and a higher resolution on the analyses. The results showed a direct relation between strict social restrictions and the loads of detected RNA reduction in wastewater, corroborating the number of confirmed cases. Differences in viral loads between different sampling points and methods were observed, as composite samples showed more stable results during the analyzed period. Besides, viral loads obtained from samples collected at Serraria WWTP were consistently higher than the ones obtained at Navegantes WWTP, indicating differences in local dynamics of SARS-CoV-2 spread in different regions of Porto Alegre. In conclusion, wastewater sampling to monitor SARS-CoV-2 is a robust tool to evaluate the viral loads contributing to hospitalized patients' data and confirmed cases. In addition, SARS-CoV-2 detection in sewage may inform and alert the government when there are asymptomatic or non-tested patients.
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The genus Orthopoxvirus (OPXV) of the family Poxviridae comprises several viruses that are capable of infecting a wide range of hosts. One of the most widespread OPXVs is the Vaccinia virus (VACV), which circulates in zoonotic cycles in South America, especially in Brazil, infecting domestic and wild animals and humans and causing economic losses as well as impacting public health. Despite this, little is known about the presence and/or exposure of neotropical primates to orthopoxviruses in the country. In this study, we report the results of a search for evidence of OPVX infections in neotropical free-living primates in the state of Minas Gerais, southeast Brazil. The sera or liver tissues of 63 neotropical primates were examined through plaque reduction neutralization tests (PRNT) and real-time PCR. OPXV-specific neutralizing antibodies were detected in two sera (4.5%) from Callithrix penicillata, showing 55% and 85% reduction in plaque counts, evidencing their previous exposure to the virus. Both individuals were collected in urban areas. All real-time PCR assays were negative. This is the first time that evidence of OPXV exposure has been detected in C. penicillata, a species that usually lives at the interface between cities and forests, increasing risks of zoonotic transmissions through spillover/spillback events. In this way, studies on the circulation of OPXV in neotropical free-living primates are necessary, especially now, with the monkeypox virus being detected in new regions of the planet.
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Gut microbiota are influenced by factors such as diet, habitat, and social contact, which directly affect the host's health. Studies related to gut microbiota in non-human primates are increasing worldwide. However, little remains known about the gut bacterial composition in wild Brazilian monkeys. Therefore, we studied the fecal microbiota composition of wild black capuchin monkey (Sapajus nigritus) (n=10) populations from two different Atlantic Forest biome fragments (five individuals per fragment) in south Brazil. The bacterial community was identified via the high-throughput sequencing and partial amplification of the 16S rRNA gene (V4 region) using an Ion Personal Genome Machine (PGMTM) System. In contrast to other studies involving monkey microbiota, which have generally reported the phyla Firmicutes and Bacteroidetes as predominant, black capuchin monkeys showed a high relative abundance of Proteobacteria ( χ ¯ = 80.54%), followed by Firmicutes ( χ ¯ = 12.14%), Actinobacteria ( χ ¯ = 4.60%), and Bacteriodetes ( χ ¯ = 1.31%). This observed particularity may have been influenced by anthropogenic actions related to the wild habitat and/or diet specific to the Brazilian biome's characteristics and/or monkey foraging behavior. Comparisons of species richness (Chao1) and diversity indices (Simpson and InvSimpson) showed no significant differences between the two groups of monkeys. Interestingly, PICRUSt2 analysis revealed that metabolic pathways present in the bacterial communities were associated with xenobiotic biodegradation and the biosynthesis of secondary metabolites, which may suggest positive effects on monkey health and conservation in this anthropogenic habitat. Infectious disease-associated microorganisms were also observed in the samples. The present study provides information about the bacterial population and metabolic functions present in fecal microbiota, which may contribute to a better understanding of the ecology and biology of black capuchin monkeys living in forest fragments within the Atlantic Forest biome in southern Brazil. Additionally, the present study demonstrates that the fecal bacterial communities of wild black capuchin monkeys in this area are divergent from those of other wild non-human primates.
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Sapajus nigritus are non-human primates which are widespread in South America. They are omnivores and live in troops of up to 40 individuals. The oral cavity is one of the main entry routes for microorganisms, including viruses. Our study proposed the identification of viral sequences from oral swabs collected in a group of capuchin monkeys (n = 5) living in a public park in a fragment of Mata Atlantica in South Brazil. Samples were submitted to nucleic acid extraction and enrichment, which was followed by the construction of libraries. After high-throughput sequencing and contig assembly, we used a pipeline to identify 11 viral families, which are Herpesviridae, Parvoviridae, Papillomaviridae, Polyomaviridae, Caulimoviridae, Iridoviridae, Astroviridae, Poxviridae, and Baculoviridae, in addition to two complete viral genomes of Anelloviridae and Genomoviridae. Some of these viruses were closely related to known viruses, while other fragments are more distantly related, with 50% of identity or less to the currently available virus sequences in databases. In addition to host-related viruses, insect and small vertebrate-related viruses were also found, as well as plant-related viruses, bringing insights about their diet. In conclusion, this viral metagenomic analysis reveals, for the first time, the profile of viruses in the oral cavity of wild, free ranging capuchin monkeys.
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Cebinae/virologia , Variação Genética , Boca/virologia , Vírus/classificação , Animais , Brasil , Genoma Viral , Sequenciamento de Nucleotídeos em Larga Escala , Metagenoma , Metagenômica , Filogenia , Sapajus , Vírus/isolamento & purificaçãoRESUMO
The sylvatic cycle of rabies, caused by the Rabies lyssavirus (RABV), is maintained in the American Continent by aerial and terrestrial wild mammals. In this study, we combined passive surveillance of rescued wild animals with active serological surveillance in targeting areas at Rio Grande do Sul State and Santa Catarina State, south of Brazil, where bites of humans by wild animals have been reported. Circulation of RABV in Brazilian bats has been extensively demonstrated; however, the observation of such infections in unvaccinated terrestrial mammals is restricted to some regions of the Brazilian territory. The occurrence of rabies infection in unvaccinated animals has been identified by the detection of RABV antigens in brain tissues of dead animals or anti-rabies antibodies in live animals. Such strategies allow the surveillance of rabies and the assessment of spillover risks from infected animals to humans. Our aim included the identification of species of wild mammals that are involved in the sylvatic cycle of rabies virus in Southern Brazil and to assess the risk of rabies infection in patients bitten by wild animals in the state. To assess the anti-rabies seropositivity, sera were submitted to the Rapid Fluorescent Focus Inhibition Test (RFFIT). Among the 100 mammals tested, five animals were seropositive (5%) including three (one primate and two wild canids) with rabies virus neutralizing antibodies titres >0.5 IU/ml. Our results highlight the exposure to RABV of both primates and wild canids in Southern Brazil and suggest the occurrence of RABV exposure without the development of further symptoms. Further research should clarify the dynamics of rabies in wild canids and whether primates are accidental hosts or reservoirs for RABV at this region.
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Quirópteros/virologia , Vírus da Raiva/isolamento & purificação , Raiva/veterinária , Animais , Animais Selvagens , Brasil/epidemiologia , Feminino , Humanos , Masculino , Mamíferos , Raiva/epidemiologia , Raiva/virologiaRESUMO
BACKGROUND Chikungunya is a mosquito-borne virus that has been causing large outbreaks in the Americas since 2014. In Brazil, Asian-Caribbean (AC) and East-Central-South-African (ECSA) genotypes have been detected and lead to large outbreaks in several Brazilian states. In Rio Grande do Sul (RS), the southernmost state of Brazil, the first cases were reported in 2016. OBJECTIVES AND METHODS We employed genome sequencing and epidemiological investigation to characterise the Chikungunya fever (CHIKF) burden in RS between 2017-2021. FINDINGS We detected an increasing CHIKF burden linked to travel associated introductions and communitary transmission of distinct lineages of the ECSA genotype during this period. MAIN CONCLUSIONS Until 2020, CHIKV introductions were most travel associated and transmission was limited. Then, in 2021, the largest outbreak occurred in the state associated with the introduction of a new ECSA lineage. CHIKV outbreaks are likely to occur in the near future due to abundant competent vectors and a susceptible population, exposing more than 11 million inhabitants to an increasing infection risk.
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BACKGROUND In Brazil, the yellow fever virus (YFV) is maintained in a sylvatic cycle involving wild mosquitoes and non-human primates (NHPs). The virus is endemic to the Amazon region; however, waves of epidemic expansion reaching other Brazilian states sporadically occur, eventually causing spillovers to humans. OBJECTIVES To report a surveillance effort that led to the first confirmation of YFV in NHPs in the state of Minas Gerais (MG), Southeast region, in 2021. METHODS A surveillance network was created, encompassing the technology of smartphone applications and coordinated actions of several research institutions and health services to monitor and investigate NHP epizootics. FINDINGS When alerts were spread through the network, samples from NHPs were collected and YFV infection confirmed by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and genome sequencing at an interval of only 10 days. Near-complete genomes were generated using the Nanopore MinION sequencer. Phylogenetic analysis indicated that viral genomes were related to the South American genotype I, clustering with a genome detected in the Amazon region (state of Pará) in 2017, named YFVPA/MG sub-lineage. Fast YFV confirmation potentialised vaccination campaigns. MAIN CONCLUSIONS A new YFV introduction was detected in MG 6 years after the beginning of the major outbreak reported in the state (2015-2018). The YFV strain was not related to the sub-lineages previously reported in MG. No human cases have been reported, suggesting the importance of coordinated surveillance of NHPs using available technologies and supporting laboratories to ensure a quick response and implementation of contingency measures to avoid YFV spillover to humans.
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Since its detection in December of 2020, the SARS-CoV2 lineage P.1, descendent of B.1.1.28 lineage, has been identified in several places in Brazil and abroad. This Variant of Concern was considered highly prevalent in Northern Brazil and now is rapidly widening its geographical range. Here, we present epidemiological and genomic information of the first case of P1 lineage in Rio Grande do Sul state, in a patient without reported travel history and a tracked transmission chain. These findings occurred in a tourist destination representing an important hub receiving tourists from diverse places.(AU)
Desde a sua detecção em dezembro de 2020, a linhagem P.1 do SARS-CoV2, descendente da linhagem B.1.1.28, foi identificada em diversos locais no Brasil e no mundo. Essa variante de preocupação era considerada altamente frequente no Norte do Brasil e agora está ampliando rapidamente sua distribuição geográfica. Aqui, apresentamos informações epidemiológicas e genômicas do primeiro caso da linhagem P.1 no Rio Grande do Sul em um paciente sem histórico de viagens relatado e com cadeia de transmissão identificada. Esses achados ocorreram em um destino turístico que representa um importante pólo de recepção de turistas de diversas localidades.(AU)
Desde su detección en diciembre de 2020, del linaje P.1 del SARS-CoV2, derivada de la B.1.1.28, hay sido ampliamente identificada en Brasil y en todo el mundo. Esta variante preocupante es muy frecuente en el norte de Brasil y ahora está ampliando rápidamente su distribución geográfica. Aquí, presentamos información epidemiológica y genómica del primer caso de P.1 en Rio Grande do Sul en un paciente sin antecedentes de viaje y con una cadena de transmisión identificada. Estos datos se han obtenido en un destino turístico que representa un importante centro de acogida de turistas de diferentes lugares.(AU)