RESUMO
We surveyed the presence of herpesvirus, flavivirus, and coronavirus in 20 Magnificent Frigatebirds (Fregata magnificens) from the protected Alcatrazes Island, Alcatrazes archipelago, Brazil. One adult female was positive for herpesvirus (5% occurrence; 95% confidence interval -5.5 to 15.5), whereas none of the samples were PCR-positive for flavivirus or coronavirus. The obtained herpesvirus was highly similar to the one responsible for annual mortality of Magnificent Frigatebird chicks on Grand Connétable Island, French Guiana; however, no episodes of mass mortality have been recorded in the birds from Alcatrazes. Our findings indicate that this virus may be widespread in Magnificent Frigatebirds of the southwestern Atlantic. The observed differences in morbidity and mortality may be the result of basal immunosuppression of the birds from French Guiana related to environmental or nutritional conditions. The Alcatrazes archipelago sustains the largest frigatebird breeding colony of the southern Atlantic; future monitoring studies with larger sampling sizes are needed to further determine the epidemiologic relevance of the detected herpesviruses, as well as other viruses (e.g., flaviviruses, coronaviruses, avian influenza virus), in seabirds of Alcatrazes Island.
Assuntos
Infecções por Coronavirus , Coronavirus , Flavivirus , Herpesviridae , Animais , Feminino , Brasil/epidemiologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/veterinária , GalinhasRESUMO
Desmodus rotundus bats show a complex social structure and developed adaptive characteristics, considered key features of a pathogen disseminator, such as the rabies virus, among bats and other mammals, including cattle and humans. Our aim was to understand the correlation between the environment and the ecological features of these bats in bovine rabies outbreaks. Geostatistical analyses were performed, covering 104 cattle positives for rabies, between 2016 and 2018, in 25 municipalities, in addition to the characteristics of D. rotundus colonies mapped during this period in the state of São Paulo, Brazil. Data from the shelters showed that 86.15% were artificial, mainly abandoned houses (36.10%) and manholes (23.87%), in addition to demonstrating a correlation between these shelters and a higher concentration of bovine rabies cases. Due to their adaptive capacity, these bats choose shelters close to the food source, such as livestock. In Brazil, D. rotundus is the main transmitter of rabies and the cause of outbreaks in cattle and deaths in humans, considering the advance of humans in previously preserved ecosystems. There seems to be a correlation between the impact of anthropic changes on the environment, mainly for the expansion of pasture for cattle and the outbreaks of bovine rabies in this area.
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To understand the population genetics events during coronavirus host switches, the Beaudette strain of Avian coronavirus (AvCoV) adapted to BHK-21 cells was passaged 15 times in VERO cells, the virus load and the variants at each passage being determined by RT-qPCR and genome-length deep sequencing. From BHK-21 P2 to VERO P3, a trend for the extinction of variants was followed by stability up to VERO P11 and both the emergence and the rise in frequency in some variants, while the virus loads were stable up to VERO P12. At the spillover from BHK-21 to VERO cells, variants that both emerged, showed a rise in frequency or were extinguished were detected on the spike, while variants at the M gene showed the same pattern only at VERO passage 13. Furthermore, nsps 3-5, 9 and 15 variants were detected at lower passages compared to the consensus sequences, with those at nsp3 being detected in the spectra also at higher passages. This suggests that quasispecies coronavirus evolution in spillovers follows the virus life cycle, starting with the evolution of the receptor binding proteins, followed by the replicase and then proteins involved in virion assembly, keeping the general fitness of the mutant spectrum stable.
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We obtained the complete sequence of a novel poxvirus, tentatively named Brazilian porcupinepox virus, from a wild porcupine (Coendou prehensilis) in Brazil that had skin and internal lesions characteristic of poxvirus infection. The impact of this lethal poxvirus on the survival of this species and its potential zoonotic importance remain to be investigated.
Assuntos
Infecções por Poxviridae , Poxviridae , Brasil , Genômica , Humanos , FilogeniaRESUMO
Avian coronavirus (AvCoV/IBV) is a virus with high morbidity, which can cause respiratory, digestive, renal, and reproductive diseases in chickens. Molecular detection and sequencing are the main tool for identification and classification of AvCoV. Thirty-six samples were collected in three broiler farms from different regions in Colombia, due to mortality increase; ten samples were positive using RT-qPCR targeted to the 5' UTR of AvCoV, and one sample was positive and had its partial S gene sequenced. Phylogenetic analysis revealed that this strain belongs to the GI-11 lineage, similar to the Brazilian cluster. Several lineages have already been described in Colombia but, to the best of our knowledge, this is the first time that GI-11 has been detected in this country, which suggests that this subtype may be more widespread in South America than previously thought.
Assuntos
Doenças Transmissíveis Emergentes , Infecções por Coronavirus/veterinária , Gammacoronavirus/classificação , Gammacoronavirus/genética , Genótipo , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/virologia , Animais , Colômbia/epidemiologia , Filogenia , Vigilância em Saúde Pública , RNA ViralRESUMO
Feline immunodeficiency virus (FIV) is an important pathogen of domestic and wild felids. Although serological tests suggest the presence of FIV in cats from Colombia, no molecular characterization has been reported. Here, we describe the near-complete genome of FIV subtype A from a Colombian domestic cat.
RESUMO
Rabies is a fatal zoonotic infection of the central nervous system of mammals and has been known to humans for millennia. The etiological agent, is a neurotropic RNA virus in the order Mononegavirales, family Rhabdoviridae, genus Lyssavirus. There are currently accepted to be two cycles for rabies transmission: the urban cycle and the sylvatic cycle. The fact that both cycles originated from a common RABV or lyssavirus ancestor and the adaptive divergence that occurred since then as this ancestor virus adapted to a wide range of fitness landscapes represented by reservoir species in the orders Carnivora and Chiroptera led to the emergence of the diverse RABV lineages currently found in the sylvatic and urban cycles. Here we study full genome phylogenies and the time to the most recent common ancestor (TMRCA) of the RABVs in the sylvatic and urban cycles. Results show that there were differences between the nucleotide substitution rates per site per year for the same RABV genes maintained independently in the urban and sylvatic cycles. The results identify the most suitable gene for phylogenetic analysis, heterotachy among RABV genes and the TMRCA for the two cycles.
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Rabies is a neurological disease with 100% lethality. Some of the rare human patients who survived after multiple drug treatment had severe sequelae. The present study showed that after 48 h of RABV inoculation, mice injected intracerebrally with anti-RABV F (ab')2 plus Bioporter® showed 70% survival compared to the control group, suggesting that transfection of anti-RABV antibodies to the brain may prevent or delay the spread of RABV at an early stage of infection. This result may provide important protocol results in intracellular antibody delivery to prevent the fatal outcome of the disease.
Assuntos
Anticorpos Antivirais/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Fragmentos Fab das Imunoglobulinas/administração & dosagem , Vacina Antirrábica/administração & dosagem , Vírus da Raiva/efeitos dos fármacos , Raiva/prevenção & controle , Vacinação/métodos , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/virologia , Modelos Animais de Doenças , Feminino , Fluoresceína-5-Isotiocianato/química , Corantes Fluorescentes/química , Humanos , Injeções Intraventriculares , Camundongos , Raiva/imunologia , Raiva/mortalidade , Raiva/virologia , Vírus da Raiva/imunologia , Vírus da Raiva/patogenicidade , Análise de Sobrevida , Transfecção/métodosRESUMO
Rotaviruses are members of the family Reoviridae and are a common cause of acute diarrhea in many mammalian and avian species. They are non-enveloped icosahedral particles and their genome comprises 11 segments of double-stranded RNA, which encodes six structural proteins (VP1-4, VP6-7) and six nonstructural proteins (NSP1-6). Genotypes are defined based upon the diversity found in these genes and viral characterization plays a central role on epidemiological studies and prevention. Here we investigate the distribution of Brazilian RVAs genotypes in 8 chicken samples collected between 2008 and 2015 from different regions by RT-PCR, partial (Sanger) nucleotide sequencing and phylogenetic analysis from all rotavirus genes. Although the identified genotypes were typical from avian host species, when analyzed together, they form novel genetic constellations: G19-P[31]-I11-R6-C6-M7-A16-N6-T8-E10-H8 and G19-P[31]-I4-R4-C4-M4-A16-N4-T4-E4-H4. This study highlights that avian rotaviruses are widespread among commercial farms in Brazil, and the co-circulation of at least two different genomic constellations indicates that may present a way bigger genetic variability, that can be increased by the possible transmission events from other birds, lack of specific preventive measures, as well as the different viral evolution mechanisms.