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Biology subjects

Miranda, T. d. S.

Publications and source records attributed to Miranda, T. d. S..

4 recordsLinked to original sources

Lessons from a multilaboratorial task force for diagnosis of a fatal toxoplasmosis outbreak in captive primates in Brazil

As exemplified by the Coronavirus Disease 2019 (COVID-19) pandemic, infectious diseases may emerge and spread rapidly, often causing serious economic losses and public health concerns. In fact, disease outbreaks have become increasingly common, especially those of zoonotic origin. The Brazilian Ministry of Health is responsible for national epizootic surveillance. However, the systems focus primarily on diseases affecting humans has led to the neglect of other zoonotic diseases. In this report, we present an integrated investigation of an outbreak that occurred during the first year of the COVID-19 pandemic among captive neotropical primates housed at a primatology center in Brazil. After presenting a range of non-specific clinical signs, including fever, prostration, inappetence, and abdominal pain, ten primates from five different species died within approximately four days. Despite the state of health emergency due to the pandemic, a network of volunteer researchers was established to investigate the outbreak. A wide range of high-resolution techniques was used for different pathogens, including SARS-CoV-2 (RTq-PCR, ELISA and IHC), Toxoplasma gondii (IHC and IFA) and Escherichia coli (IFA), as well as a portable Metagenomic Sequencing utilizing Nanopore Technology. Within a span of four days after necropsies, we successfully identified T. gondii as the causative agent of this outbreak. This case highlights some of the obstacles faced with the current Brazilian surveillance system, which is still limited. A cross-platform interdisciplinary investigation could be a possible model for future epizootic investigations in non-human animals. Author summaryThe Brazilian epizootic surveillance system, under the regulation of the Ministry of Health, has been established to address a national list of compulsory notifiable diseases. However, focusing mainly on the risks to humans causes other zoonoses to be neglected. Here we present an outbreak that occurred during the first year of the COVID-19 pandemic that affected eleven neotropical primates (NP) belonging to six different species. Within four days of exhibiting a range of non-specific clinical signs, including fever, prostration, inappetence, and abdominal pain, ten NPs died. Despite testing negative for pathogens included in the national surveillance policy, a collaborative group of researchers investigated the outbreak in detail. Using integrated diagnostic techniques, we identified Toxoplasma gondii as the causative agent four days after necropsy. Toxoplasmosis causes devastating acute death outbreaks in neotropical primates and is currently absent in the national guidelines. This unified effort proved the effectiveness of a multidisciplinary collaborative surveillance network in facilitating precise diagnoses.

microbiology↗

Fecal Virome of Coendou spinosus (Paraguaian Hairy Dwarf Porcupine)

The porcupine (Coendou spinosus) is a rodent species widely distributed in the Brazilian Atlantic forest. Like other rodent species, porcupines can be potential reservoirs of zoonotic agents. However, little is known about the viral diversity in these animals. Therefore, the objective of the present study was to evaluate, through massive sequencing, the virome of the feces of seven adult healthy free-living porcupines living in forest fragments from Silva Jardim, State of Rio de Janeiro, Brazil. A total of 41 viral families were classified, of which only seven were validated by both Kraken2 and Diamond taxonomic analysis tools, including bacteriophages (Siphoviridae, Myoviridae, Podoviridae), vertebrate viruses, such as Papillomaviridae, and unclassified RNA viruses. In addition, we also observed the presence of pathogenic bacteria and fungi already described in porcupines. The present study describes for the first time the microbiome in fecal samples from Brazilian porcupines, contributing to the global metagenomic characterization.

microbiology↗

Fecal Virome of Southeastern Maned Sloth (Bradypus crinitus)

We report a viral metagenomic analysis of fecal samples from Bradypus crinitus, a recently described sloth species that occurs in the Atlantic Forest of Espirito Santo and Rio de Janeiro states, Southeast Brazil. Through Illumina sequencing, we generated a total of 2,065,344 raw reads, of which 945,386 reads (45.77%) passed the quality and size filter. The highest proportion of them was assigned to Eukarya, followed by Bacteria and only a small proportion to Virus. However, we identified 24 viral families using distinct taxonomic assignment tools, including phages and vertebrate viruses, such as retroviruses and papillomaviruses. Also, we identified four bacterial genus already associated with disease in sloths. Our study sheds light on the microbiome of a previously unexplored species, further contributing to the comprehension of metagenomic global diversity.

genetics↗

Metagenomic analysis reveals novel dietary-related viruses in the gut virome of marmosets hybrids (Callithrix jacchus x Callithrix penicillata), Brazil

Viral metagenomics has contributed enormously to the characterization of a wide range of viruses infecting animals of all phyla in the last decades. Among Neotropical primates, especially those free-living introduced, knowledge about viral diversity remains poorly studied. Therefore, through the use of metagenomics based on virus enrichment, we explored the viral microbiota present in the feces of introduced common marmosets (Callithrix sp.) in three locations from the Silva Jardim region in the State of Rio de Janeiro, Brazil. Fecal samples were collected from nine marmosets, pooled into three sample pools and sequenced on Illumina MiSeq platform. Sequence reads were analyzed using a viral metagenomic analysis pipeline and two novel insect viruses belonging to the Parvoviridae and Baculoviridae families were identified. The complete genome of a densovirus (Parvoviridae family) of 5,309 nucleotides (nt) was obtained. The NS1 and VP1 proteins share lower than 32% sequence identity with the corresponding proteins of known members of the subfamily Densovirinae. Phylogenetic analysis suggests that this virus represents a new genus, named Tritonambidensovirus due to telomeric structures at the 3 and 5 ends of the genome. The novel species received the name Fecalis tritonambidensovirus 1. The complete circular genome of a baculovirus of 107,191 nt was also obtained, showing 60.8% sequence identity with the most closely related member of the Baculoviridae family. Phylogenetic analysis suggests that this virus represents a new species of Betabaculovirus, named Callithrix fecalis granulovirus. In addition, sequences from several families of arthropods in the three pools evaluated were characterized (contigs ranging from 244 to 6,750 nt), corroborating the presence of possible insect hosts with which these new viruses may be associated. Our study expands the knowledge about two viral families known to infect insects, an important component of the marmosets diet. This identification in hosts feces samples demonstrates one of the many uses of this type of data and could serve as a basis for future research characterizing viruses in wildlife using noninvasive samples.

genomics↗