Tatiana Ometto

West Nile virus surveillance, Brazil, 2008-2010

BACKGROUND West Nile virus (WNV) is an emergent pathogen that is widely distributed in North and Central America. The recent introduction in South America has focused attention on the spread of WNV across Southern American countries. The transmission network involves mosquitoes, birds, horses and humans. METHODS The serological evaluation of sera from 678 equids and 478 birds was performed using a WNV-specific blocking ELISA, and only the positive results were confirmed by plaque reduction neutralisation tests (PRNTs). Molecular analysis was performed on sera from 992 healthy equids and on 63 macerates of brains from equids that died of encephalitis and had previously tested negative for other pathogens. We also tested swabs from 928 birds. The samples analysed were collected in different biomes of Brazil. RESULTS We identified WNV antibodies by ELISA in thirteen equids and five birds, and PRNT90 confirmed WNV positivity in four equid samples collected in 2009 in an area between the Amazon and the Pantanal. None of the ELISA positive bird samples were confirmed by PRNT90, and all samples tested by RT-PCR were negative. CONCLUSION WNV circulation is confirmed by this large scale survey even in the absence of detection of clinical cases.

Avian Influenza Virus (H11N9) in Migratory Shorebirds Wintering in the Amazon Region, Brazil

Aquatic birds are the natural reservoir for avian influenza viruses (AIV). Habitats in Brazil provide stopover and wintering sites for water birds that migrate between North and South America. The current study was conducted to elucidate the possibility of the transport of influenza A viruses by birds that migrate annually between the Northern and Southern Hemispheres. In total, 556 orotracheal/cloacal swab samples were collected for influenza A virus screening using real-time RT-PCR (rRT-PCR). The influenza A virus-positive samples were subjected to viral isolation. Four samples were positive for the influenza A matrix gene by rRT-PCR. From these samples, three viruses were isolated, sequenced and characterized. All positive samples originated from a single bird species, the ruddy turnstone (Arenaria interpres), that was caught in the Amazon region at Caeté Bay, Northeast Pará, at Ilha de Canelas. To our knowledge, this is the first isolation of H11N9 in the ruddy turnstone in South America.

Detection of hantavirus in bats from remaining rain forest in São Paulo, Brazil

BackgroundThe significant biodiversity found in Brazil is a potential for the emergence of new zoonoses. Study in some places of the world suggest of the presence to hantavirus in tissues of bats. Researches of hantavirus in wildlife, out rodents, are very scarce in Brazil. Therefore we decided to investigate in tissues of different species of wild animals captured in the same region where rodents were detected positive for this virus. The present work analyzed ninety-one animals (64 rodents, 19 opossums, and 8 bats) from a region of the Atlantic forest in Biritiba Mirin City, São Paulo State, Brazil. Lungs and kidneys were used for RNA extraction.FindingsThe samples were screened for evidence of hantavirus infection by SYBR-Green-based real-time RT-PCR. Sixteen samples positive were encountered among the wild rodents, bats, and opossums. The detection of hantavirus in the lungs and kidneys of three marsupial species (Micoureus paraguayanus, Monodelphis ihering, and Didelphis aurita) as well in two species of bats (Diphylla ecaudata and Anoura caudifer) is of significance because these new hosts could represent an important virus reservoirs.ConclusionsThe analysis of nucleotide sequences of the partial S segment revealed that these genes were more related to the Araraquara virus strains. This work reinforces the importance of studying hantavirus in different animal species and performing a continued surveillance before this virus spreads in new hosts and generated serious problems in public health.

Molecular surveillance of the Newcastle disease virus in domestic and wild birds on the North Eastern Coast and Amazon biome of Brazil

Brazil is one of the worlds largest countries with a rich diversity of wildlife, including resident and migratory wild birds, which may be natural reservoirs of the Newcastle disease virus (NDV). Because Brazil is a major global exporter of chicken meat, the emergence of such a disease may have a huge negative impact not only on the economy due to trade restrictions and embargoes, but also on the quality of life of the population. Samples were collected from 1,022 asymptomatic domestic and wild birds from the Brazilian coast and the Amazon region using tracheal/cloacal swabs and tested by RT-qPCR. The results showed 7 (0.7%) birds were positive for NDV. The positive samples were then isolated in embryonated chicken eggs and their matrix protein genes were partially sequenced, revealing a low-pathogenicity NDV. This study confirms the maintenance of the velogenic-NDV free status of Brazil.

Novel avian paramyxovirus (APMV-15) isolated from a migratory bird in South America

A novel avian paramyxovirus (APMV) isolated from a migratory bird cloacal swab obtained during active surveillance in April 2012 in the Lagoa do Peixe National Park, Rio Grande do Sul state, South of Brazil was biologically and genetically characterized. The nucleotide sequence of the full viral genome was completed using a next-generation sequencing approach. The genome was 14,952 nucleotides (nt) long, with six genes (3’-NP-P-M-F-HN-L-5’) encoding 7 different proteins, typical of APMV. The fusion (F) protein gene of isolate RS-1177 contained 1,707 nucleotides in a single open reading frame encoding a protein of 569 amino acids. The F protein cleavage site contained two basic amino acids (VPKER↓L), typical of avirulent strains. Phylogenetic analysis of the whole genome indicated that the virus is related to APMV-10, -2 and -8, with 60.1% nucleotide sequence identity to the closest APMV-10 virus, 58.7% and 58.5% identity to the closest APMV-8 and APMV-2 genome, respectively, and less than 52% identity to representatives of the other APMVs groups. Such distances are comparable to the distances observed among other previously identified APMVs serotypes. These results suggest that unclassified/calidris_fuscicollis/Brazil/RS-1177/2012 is the prototype strain of a new APMV serotype, APMV-15.

Detection of hantaviruses in Brazilian rodents by SYBR-Green-based real-time RT-PCR

Current knowledge of the pathogenic hantavirus indicates that wild rodents are its primary natural reservoir. Specific primers to detect the presence of viral genomes were developed using an SYBR-Green-based real-time RT-PCR protocol. One hundred sixty-four rodents native to the Atlantic Forest biome were captured in São Paulo State, Brazil, and their tissues were tested. The presence of hantavirus RNA was detected in sixteen rodents: three specimens of Akodon montensis, three of Akodon cursor, two of Necromys lasiurus, one of Juliomys sp., one of Thaptomys nigrita, five of Oligoryzomys nigripes, and one of Oryzomys sp. This SYBR Green real-time RT-PCR method for detection of hantavirus may be useful for surveying hantaviruses in Brazil.

Co-circulation in a single biome of the Juquitiba and Araraquara hantavirus detected in human sera in a sub-tropical region of Brazil.

Hantaviruses is an emerging infectious disease. Although HCPS has been reported in several regions of Brazil, more cases of HCPS have recently been reported in Minas Gerais than in any other state. In 2009, we analyzed 27 samples presenting antibodies against hantaviruses. These samples originated from 688 symptomatic patients, as determined based on the Hemorrhagic Fever Protocol. A subsequent SYBR Green‐based real‐time RT‐PCR demonstrated the presence of the virus in 22 of the samples. Among the RT‐PCR‐positive samples, 17 were analyzed using DNA sequencing; these sequences were compared with others deposited in GenBank and showed similarity with the Araraquara and Juquitiba virus clusters. This work describe the detection of Juquitiba virus, including three fatal cases, in Minas Gerais state, furthermore, showed that it is feasible to characterize the circulating strains using a small fragment of S segment. Finally, the results suggest the co‐circulation of Araraquara and Juquitiba virus in a single biome in Minas Gerais state. J. Med. Virol. 87:725–732, 2015.

Absence of Anaplasmataceae DNA in Wild Birds and Bats from a Flooded Area in the Brazilian Northern Pantanal

Birds and bats can be considered potential transmitters of some tick-borne diseases, since eventually they carry infected ticks in areas where transit. Pantanal ecosystem is the largest tropical wetland area of the world with more than 582 recorded avian species, contributing to the maintenance of different tick species. The aim of this study was to examine altogether 152 blood samples of several bird and bat species collected in a large flooded area of Pantanal for the presence of members from genera Ehrlichia, Anaplasma and Neorickettsia. None PCR product was obtained, what suggest that wild, domestic birds and bats from Pantanal region are unlikely to play a significant role in the maintenance of tick-borne agents and DNA survey from this species in birds may not be a reliable indicator of exposure.

Surveillance of Avian Influenza Virus in Aquatic Birds on the Brazilian Amazon Coast

The occurrence of avian influenza viruses (AIV) has been extensively studied in aquatic birds in the Northern hemisphere; however, much less information is available for the South American region. In 2009–2010, we sampled 1006 wild aquatic birds (90% Charadriiformes, 9% Anseriformes, and 1% other groups) at three locations on the Brazilian Amazon coast, a region that serves as a major stop-over and wintering site along the Atlantic Americas flyway. Real-time RT-PCR identified five samples as positive; however, no AIV isolates could be obtained and Illumina sequencing did not produce gene sequences that would allow further characterization of the virus.

Novel Parvoviruses from Wild and Domestic Animals in Brazil Provide New Insights into Parvovirus Distribution and Diversity

Parvoviruses (family Parvoviridae) are small, single-stranded DNA viruses. Many parvoviral pathogens of medical, veterinary and ecological importance have been identified. In this study, we used high-throughput sequencing (HTS) to investigate the diversity of parvoviruses infecting wild and domestic animals in Brazil. We identified 21 parvovirus sequences (including twelve nearly complete genomes and nine partial genomes) in samples derived from rodents, bats, opossums, birds and cattle in Pernambuco, São Paulo, Paraná and Rio Grande do Sul states. These sequences were investigated using phylogenetic and distance-based approaches and were thereby classified into eight parvovirus species (six of which have not been described previously), representing six distinct genera in the subfamily Parvovirinae. Our findings extend the known biogeographic range of previously characterized parvovirus species and the known host range of three parvovirus genera (Dependovirus, Aveparvovirus and Tetraparvovirus). Moreover, our investigation provides a window into the ecological dynamics of parvovirus infections in vertebrates, revealing that many parvovirus genera contain well-defined sub-lineages that circulate widely throughout the world within particular taxonomic groups of hosts.