RESUMO
The Red Queen Hypothesis (RQH), derived from Lewis Carroll's "Through the Looking-Glass", postulates that organisms must continually adapt in response to each other to maintain relative fitness. Within the context of host-pathogen interactions, the RQH implies an evolutionary arms race, wherein viruses evolve to exploit hosts and hosts evolve to resist viral invasion. This study delves into the dynamics of the RQH in the context of virus-cell interactions, specifically focusing on virus receptors and cell receptors. We observed multiple virus-host systems and noted patterns of co-evolution. As viruses evolved receptor-binding proteins to effectively engage with cell receptors, cells countered by altering their receptor genes. This ongoing mutual adaptation cycle has influenced the molecular intricacies of receptor-ligand interactions. Our data supports the RQH as a driving force behind the diversification and specialization of both viral and host cell receptors. Understanding this co-evolutionary dance offers insights into the unpredictability of emerging viral diseases and potential therapeutic interventions. Future research is crucial to dissect the nuanced molecular changes and the broader ecological consequences of this ever-evolving battle. Here, we combine phylogenetic inferences, structural modeling, and molecular dynamics analyses to describe the epidemiological characteristics of major Brazilian DENV strains that circulated from 1990 to 2022 from a combined perspective, thus providing us with a more detailed picture on the dynamics of such interactions over time.
Assuntos
Moléculas de Adesão Celular , Vírus da Dengue , Evolução Molecular , Interações Hospedeiro-Patógeno , Receptores de Superfície Celular , Proteínas do Envelope Viral , Envelope Viral , Humanos , Brasil , Moléculas de Adesão Celular/metabolismo , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/química , Dengue/virologia , Vírus da Dengue/genética , Vírus da Dengue/metabolismo , Interações Hospedeiro-Patógeno/genética , Lectinas Tipo C/metabolismo , Lectinas Tipo C/genética , Lectinas Tipo C/química , Simulação de Dinâmica Molecular , Filogenia , Ligação Proteica , Receptores de Superfície Celular/metabolismo , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/química , Receptores Virais/metabolismo , Receptores Virais/química , Receptores Virais/genética , Envelope Viral/metabolismo , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/metabolismo , Proteínas do Envelope Viral/químicaRESUMO
BACKGROUND: Chikungunya virus (CHIKV) has spread across Brazil with varying incidence rates depending on the affected areas. Due to cocirculation of arboviruses and overlapping disease symptoms, CHIKV infection may be underdiagnosed. To understand the lack of CHIKV epidemics in São José do Rio Preto (SJdRP), São Paulo (SP), Brazil, we evaluated viral circulation by investigating anti-CHIKV IgG seroconversion in a prospective study of asymptomatic individuals and detecting anti-CHIKV IgM in individuals suspected of dengue infection, as well as CHIKV presence in Aedes mosquitoes. The opportunity to assess two different groups (symptomatic and asymptomatic) exposed at the same geographic region aimed to broaden the possibility of identifying the viral circulation, which had been previously considered absent. METHODOLOGY/PRINCIPAL FINDINGS: Based on a prospective population study model and demographic characteristics (sex and age), we analyzed the anti-CHIKV IgG seroconversion rate in 341 subjects by ELISA over four years. The seroprevalence increased from 0.35% in the first year to 2.3% after 3 years of follow-up. Additionally, we investigated 497 samples from a blood panel collected from dengue-suspected individuals during the 2019 dengue outbreak in SJdRP. In total, 4.4% were positive for anti-CHIKV IgM, and 8.6% were positive for IgG. To exclude alphavirus cross-reactivity, we evaluated the presence of anti-Mayaro virus (MAYV) IgG by ELISA, and the positivity rate was 0.3% in the population study and 0.8% in the blood panel samples. In CHIKV and MAYV plaque reduction neutralization tests (PRNTs), the positivity rate for CHIKV-neutralizing antibodies in these ELISA-positive samples was 46.7%, while no MAYV-neutralizing antibodies were detected. Genomic sequencing and phylogenetic analysis revealed CHIKV genotype ECSA in São José do Rio Preto, SP. Finally, mosquitoes collected to complement human surveillance revealed CHIKV positivity of 2.76% of A. aegypti and 9.09% of A. albopictus (although it was far less abundant than A. aegypti) by RT-qPCR. CONCLUSIONS/SIGNIFICANCE: Our data suggest cryptic CHIKV circulation in SJdRP detected by continual active surveillance. These low levels, but increasing, of viral circulation highlight the possibility of CHIKV outbreaks, as there is a large naïve population. Improved knowledge of the epidemiological situation might aid in outbreaks prevention.
Assuntos
Aedes , Febre de Chikungunya , Vírus Chikungunya , Dengue , Animais , Humanos , Vírus Chikungunya/genética , Estudos Prospectivos , Brasil/epidemiologia , Filogenia , Estudos Soroepidemiológicos , Febre de Chikungunya/epidemiologia , Anticorpos Antivirais , Dengue/diagnóstico , Dengue/epidemiologia , Anticorpos Neutralizantes/genética , Imunoglobulina G , Imunoglobulina MRESUMO
BACKGROUND: Chikungunya virus (CHIKV) is an Aedes mosquito-borne virus that has caused large epidemics linked to acute, chronic, and severe clinical outcomes. Currently, Brazil has the highest number of chikungunya cases in the Americas. We aimed to investigate the spatiotemporal dynamics and recurrence pattern of chikungunya in Brazil since its introduction in 2013. METHODS: In this epidemiological study, we used CHIKV genomic sequencing data, CHIKV vector information, and aggregate clinical data on chikungunya cases from Brazil. The genomic data comprised 241 Brazilian CHIKV genome sequences from GenBank (n=180) and the 2022 CHIKV outbreak in Ceará state (n=61). The vector data (Breteau index and House index) were obtained from the Brazilian Ministry of Health for all 184 municipalities in Ceará state and 116 municipalities in Tocantins state in 2022. Epidemiological data on laboratory-confirmed cases of chikungunya between 2013 and 2022 were obtained from the Brazilian Ministry of Health and Laboratory of Public Health of Ceará. We assessed the spatiotemporal dynamics of chikungunya in Brazil via time series, mapping, age-sex distribution, cumulative case-fatality, linear correlation, logistic regression, and phylogenetic analyses. FINDINGS: Between March 3, 2013, and June 4, 2022, 253 545 laboratory-confirmed chikungunya cases were reported in 3316 (59·5%) of 5570 municipalities, mainly distributed in seven epidemic waves from 2016 to 2022. To date, Ceará in the northeast has been the most affected state, with 77 418 cases during the two largest epidemic waves in 2016 and 2017 and the third wave in 2022. From 2016 to 2022 in Ceará, the odds of being CHIKV-positive were higher in females than in males (odds ratio 0·87, 95% CI 0·85-0·89, p<0·0001), and the cumulative case-fatality ratio was 1·3 deaths per 1000 cases. Chikungunya recurrences in the states of Ceará, Tocantins (recurrence in 2022), and Pernambuco (recurrence in 2021) were limited to municipalities with few or no previously reported cases in the previous epidemic waves. The recurrence of chikungunya in Ceará in 2022 was associated with a new East-Central-South-African lineage. Population density metrics of the main CHIKV vector in Brazil, Aedes aegypti, were not correlated spatially with locations of chikungunya recurrence in Ceará and Tocantins. INTERPRETATION: Spatial heterogeneity of CHIKV spread and population immunity might explain the recurrence pattern of chikungunya in Brazil. These results can be used to inform public health interventions to prevent future chikungunya epidemic waves in urban settings. FUNDING: Global Virus Network, Burroughs Wellcome Fund, Wellcome Trust, US National Institutes of Health, São Paulo Research Foundation, Brazil Ministry of Education, UK Medical Research Council, Brazilian National Council for Scientific and Technological Development, and UK Royal Society. TRANSLATION: For the Portuguese translation of the abstract see Supplementary Materials section.
Assuntos
Aedes , Febre de Chikungunya , Vírus Chikungunya , Masculino , Animais , Feminino , Humanos , Vírus Chikungunya/genética , Febre de Chikungunya/epidemiologia , Brasil/epidemiologia , Filogenia , Mosquitos Vetores , Estudos EpidemiológicosRESUMO
Chaphamaparvovirus (CHPV) is a recently characterized genus of the Parvoviridae family whose members can infect different hosts, including bats, which constitute the second most diverse order of mammals and are described worldwide as important transmitters of zoonotic diseases. In this study, we identified a new CHPV in bat samples from the municipality of Santarém (Pará state, North Brazil). A total of 18 Molossus molossus bats were analyzed using viral metagenomics. In five animals, we identified CHPVs. These CHPV sequences presented the genome with a size ranging from 3797 to 4284 bp. Phylogenetic analysis-based nucleotide and amino acid sequences of the VP1 and NS1 regions showed that all CHPV sequences are monophyletic. They are also closely related to CHPV sequences previously identified in bats in southern and southeast Brazil. According to the International Committee on Taxonomy of Viruses (ICTV) classification criteria for this species (the CHPV NS1 gene region must have 85% identity to be classified in the same species), our sequences are likely a new specie within the genus Chaphamaparvovirus, since they have less than 80% identity with other CHPV described earlier in bats. We also make some phylogenetic considerations about the interaction between CHPV and their host. We suggest a high level of specificity of CPHV and its hosts. Thus, the findings contribute to improving information about the viral diversity of parvoviruses and show the importance of better investigating bats, considering that they harbor a variety of viruses that may favor zoonotic events.
Assuntos
Quirópteros , Parvovirus , Animais , Filogenia , Brasil/epidemiologia , MamíferosRESUMO
Capybara (Hydrochoerus hydrochaeris) is the world's largest rodent species distributed throughout South America. These animals are incredibly tolerant to anthropogenic environments and are occupying large urban centers. Capybaras are known to carry potentially zoonotic agents, including R. rickettsia, Leishmania spp., Leptospira spp., Trypanosoma spp., Salmonella spp., Toxoplasma gondii, and rabies virus. Focusing on the importance of monitoring potential sources of emerging zoonotic viruses and new viral reservoirs, the aim of the present study was to assess the presence of fecal-borne viruses in the feces of capybaras living in urban parks in São Paulo state, Brazil. A total of 337 fecal samples were collected between 2018 and 2020 and screened for the following: (i) Rotavirus group A (RVA) by ELISA; (ii) non-RVA species and Picobirnavirus (PBV) using PAGE; (iii) Human Bocaparvovirus (HBoV), Bufavirus (BuV), Tusavirus (TuV), and Cutavirus (CuV) qPCR; (iv) Human Enterovirus (EV), Norovirus GII (NoV), and Hantavirus by in houses RT-qPCR; (v) SARS-CoV-2 via commercial RT-qPCR kit assay; and (vi) Astrovirus (AstV) and Adenovirus (AdV) using conventional nested (RT)-PCRs. All fecal samples tested were negative for fecal-borne viruses. This study adds further evidence that the fecal-borne viruses is a minor public health issue in Brazilian capybaras, at least during the surveillance period and surveyed areas. Continuous monitoring of sylvatic animals is essential to prevent and control the emergence or re-emergence of newly discovered virus as well as viruses with known zoonotic potential.
Assuntos
COVID-19 , Saúde Pública , Animais , Humanos , Brasil/epidemiologia , Roedores/microbiologia , SARS-CoV-2 , FezesRESUMO
The totiviridae family contains viruses with double-stranded RNA genomes of 4.6-7.0 kpb, which encode a capsid protein (CP) and RNA-dependent RNA polymerase (RdRp), and they are approximately 40 nm in diameter with icosahedral symmetry. Totiviruses were first isolated from mosquitoes collected in Shaanxi Province (China). Here, we report a new Aedes aegypti Totivirus (AaTV) identified in mosquitoes from the Amazon rainforest. Mosquitoes (Diptera: Culicidae) were collected from a forest reserve belonging to the Amazon forest in the city of Macapá, Amapá state, Northern Brazil. A viral sequence with a 5748 nucleotide length that was nearly identical to Aedes aegypti Totivirus (AaTV), here named Aedes aegypti Totivirus BR59AP, was detected. A detailed molecular analysis was performed and shows that AaTV-BR59AP is highly related to the AaTV strain from the Caribbean region. We emphasize the importance of the characterization of new viruses in mosquitoes to deepen our understanding of viral diversity in insects and their potential role in disease.
Assuntos
Aedes , Totiviridae , Totivirus , Vírus , Animais , Totivirus/genética , Brasil , Totiviridae/genéticaRESUMO
The simultaneous transmission of two lineages of the chikungunya virus (CHIKV) was discovered after the pathogen's initial arrival in Brazil. In Oiapoque (Amapá state, north Brazil), the Asian lineage (CHIKV-Asian) was discovered, while in Bahia state, the East-Central-South-African lineage (CHIKV-ECSA) was discovered (northeast Brazil). Since then, the CHIKV-Asian lineage has been restricted to the Amazon region (mostly in the state of Amapá), whereas the ECSA lineage has expanded across the country. Despite the fact that the Asian lineage was already present in the Amazon region, the ECSA lineage brought from the northeast caused a large outbreak in the Amazonian state of Roraima (north Brazil) in 2017. Here, CHIKV spread in the Amazon region was studied by a Zika-Dengue-Chikungunya PCR assay in 824 serum samples collected between 2013 and 2016 from individuals with symptoms of viral infection in the Amapá state. We found 11 samples positive for CHIKV-Asian, and, from these samples, we were able to retrieve 10 full-length viral genomes. A comprehensive phylogenetic study revealed that nine CHIKV sequences came from a local transmission cluster related to Caribbean strains, whereas one sequence was related to sequences from the Philippines. These findings imply that CHIKV spread in different ways in Roraima and Amapá, despite the fact that both states had similar climatic circumstances and mosquito vector frequencies.
Assuntos
Febre de Chikungunya , Vírus Chikungunya , Infecção por Zika virus , Zika virus , Animais , Brasil/epidemiologia , Região do Caribe , Vírus Chikungunya/genética , Surtos de Doenças , Genótipo , Humanos , Filogenia , Infecção por Zika virus/epidemiologiaRESUMO
Putative replication-associated protein (REP) and capsid-like (CAP) proteins are encoded by circular single-stranded DNA viruses (CRESS DNA), which have been found in samples from most eukaryotic groups. However, the details of these viruses' life cycles and their significance in diseases have yet to be established. We presented and analyzed two full-length CRESS DNA genomes acquired from two children diagnosed with acute gastroenteritis (GI) in the northeast state of Tocantins, Brazil, using next-generation sequencing and a virus-like filtration approach. Both sequences (named SmaCV3BR08 and SmaCV3BR291) are closely similar to a prior CRESS DNA sequence discovered in the feces of a new world monkey (Alouatta caraya) from the United States in 2009 and termed Howler monkey-associated porprismacovirus 1 (Genbank ID: NC 026317). According to our comparative study, these porprismacovirus genomes deviate by 10% at the nucleotide level. For comparative reasons, the divergence between our sequences (SmaCV3BR08 and SmaCV3BR291) and a porprismacovirus recently identified in a human fecal sample from Peru is 37%. These data suggest that there is a great diversity of porprismacoviruses in South America, perhaps more than two species. In addition, the finding of closely related sequences of porprismacoviruses in humans and native monkeys highlights the zoonotic potential of these viruses.