Publications by authors named "Bernardo R Teixeira"

Article Synopsis
  • Hemotropic mycoplasmas, or hemoplasmas, are a group of bacteria found in various animal species and the study aimed to explore their presence and genetic diversity among small non-flying mammals in Brazil, focusing on environmental and animal factors affecting infection rates.* ! -
  • Out of 257 sampled animals, 33.8% tested positive for hemotropic mycoplasma DNA, with the highest infection rates observed in the regions of Ponta Grossa and Cruz Machado and specifically in the rodent species Oligoryzomys.* ! -
  • The study identified two phylogenetic clades of hemoplasmas and showed that males were significantly more likely to be infected than females, emphasizing the influence of
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The predominant landscape of the Atlantic Forest of the Brazilian state of Rio de Janeiro is made up of forest fragments surrounded by a matrix of modified habitat, which may influence the occurrence and distribution of host species and their parasites in comparison with the original continuous forest. The present study describes the structure, composition, and diversity of the helminth community found in rodents in two areas of an open matrix of different status of conservation. The abundance, intensity, and prevalence were calculated for each helminth species in rodent species.

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In Brazil, the first confirmed cases of hantavirus cardiopulmonary syndrome in Indigenous populations occurred in 2001. The purpose of this study was to determine the seroprevalence of orthohantavirus infections in the Utiariti Indigenous land located in the southeastern region of the Brazilian Amazon. In December 2014 and 2015, a survey was conducted using an enzyme-linked immunosorbent assay in nine villages belonging to the Haliti-Paresí Indigenous communities.

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is a bacteria that causes leptospirosis and is transmitted through water, soil, or mud that is contaminated by the urine of infected animals. Although it is mainly associated with the urban environment, Leptospires also circulate in rural and wild environments. This study aimed to investigate the role of small mammals in leptospirosis epidemiology in the western Amazon, Brazil.

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The species are zoonotic agents that infect mammals and are transmitted by arthropod vectors. Approximately 18 distinct genotypes cause diseases in humans, and may be spread by both domestic and wild animals. In Brazil, genotypes have been identified in several species of wild mammals, and in the present study, we analyzed samples from non-human primates (marmosets), marsupials, rodents, and bats, and compared them with the genotypes described in mammals from Brazil, to examine the distribution of genotypes in two impacted areas of Rio de Janeiro state, in southeastern Brazil.

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Introduction: The Amazon tropical rainforest has the most dense and diverse ecosystem worldwide. A few studies have addressed rodent-borne diseases as potential hazards to humans in this region.

Methods: A retrospective survey was conducted using enzyme-linked immunosorbent assay for detecting mammarenavirus and orthohantavirus antibodies in 206 samples collected from rural settlers of the Brazilian Western Amazonian region.

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During the Brazilian slavery period, many African migrants were brought to the American continent. Historically, some of these migrants escaped from the Brazilian gold mines and farms to which they had been brought and settled in remote valleys and this was the main mode of resistance to the slavery system. These runaway-slave descendant communities are called quilombos, a group with distinct ethnic identity, specific behavioral habits, including geographic isolation and conservative practices.

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The enteric protist Blastocystis is one of the most frequently reported parasites infecting both humans and many other animal hosts worldwide. A remarkable genetic diversity has been observed in the species, with 17 different subtypes (STs) on a molecular phylogeny based on small subunit RNA genes (SSU rDNA). Nonetheless, information regarding its distribution, diversity and zoonotic potential remains still scarce, especially in groups other than primates.

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Many snail species act as intermediate hosts of helminths that transmit diseases to humans and animals, such as schistosomiasis and angiostrongyliasis. São Gonçalo, a mostly urban municipality in Rio de Janeiro State, Brazil, has undergone fundamental environmental impacts, which favor the establishment of a range of diseases, for which snails act as the intermediate hosts of the etiological agents. In the present study, freshwater and terrestrial snail populations were surveyed in different environments within five city districts, and the presence of helminths was determined in the collected specimens.

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Necromys lasiurus is a generalist rodent that is thought to be the main reservoir of the Araraquara hantavirus, which causes Hantavirus Pulmonary Syndrome, in the Brazilian Cerrado savanna. This species occurs naturally in the open habitats of the Cerrado, Pantanal and Caatinga biomes, where it often occurs at high densities, although the distribution of the species has recently been observed expanding into the Brazilian state of Rio de Janeiro. This study aimed to map the occurrence of N.

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Mammarenavirus RNA was detected in Musser's bristly mouse (Neacomys musseri) from the Amazon region, and this detection indicated that rodents were infected with a novel mammarenavirus, with the proposed name Xapuri virus (XAPV), which is phylogenetically related to New World Clade B and Clade C viruses. XAPV may represent the first natural reassortment of the Arenaviridae family and a new unrecognized clade within the Tacaribe serocomplex group.

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Article Synopsis
  • Mammarenaviruses are typically associated with specific rodent host species, but recent findings indicate that multiple host species may harbor these viruses, challenging previous assumptions about their co-evolution.
  • A study in Brazil identified a new rodent reservoir species (Calomys callidus) linked to the Latino mammarenavirus (LATV), with genetic analysis revealing a well-supported group of LATV strains.
  • The research suggests that our understanding of mammarenavirus dynamics in South America is evolving, indicating that further studies in non-endemic areas may uncover additional animal hosts for these viruses.
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Hantavirus cardiopulmonary syndrome is an emerging serious disease in the Americas, transmitted from wild rodents to humans through inhalation of aerosol containing virus. Herein, we characterized two distinct hantaviruses circulating in rodent species form Central Plateau, Midwestern region of Brazil in the Cerrado (savanna-like) biome, an area characterized by small trees and grasses adapted to climates with long dry periods. In this study, we identified the co-circulation of the Araraquara virus and a possible new lineage of the Juquitiba virus (JUQV) in Oligoryzomys nigripes.

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We report the results of an investigation into a fatal case of hantavirus pulmonary syndrome (HPS) in Rio de Janeiro State, Brazil, where the disease had not been reported previous to 2015. Following the notification of an HPS case, serum samples were collected from the household members and work contacts of the HPS patient and tested for antibody to hantaviruses. Seroprevalence of 22% (10/45) was indicated for hantavirus out of 45 human samples tested.

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Zoonotic pathogens comprise a significant and increasing fraction of all emerging and re-emerging infectious diseases that plague humans. Identifying host species is one of the keys to controlling emerging infectious diseases. From March 2007 until April 2012, we collected a total of 131 wild rodents in eight municipalities of Rio de Janeiro, Brazil.

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Information about tick fauna and monitoring of pathogen prevalences in ticks (Acari: Ixodidae) in various habitat types can enhance knowledge about the epidemiology of tick-borne pathogens in Brazil. This work shows the results of a study of tick parasitism of wild rodents and marsupials collected in seven localities in the southern part of Brazil, within Atlantic Forest and Cerrado biomes. A total of 61 ticks were collected from small mammals, and after identification to the species level, the ticks were individually tested for the presence of bacteria of the genera Rickettsia, Borrelia, family Anaplasmataceae, and protozoa of the genus Babesia.

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In this study we analyze population dynamics of hantavirus rodent hosts and prevalence of infection over a 2-year period in Southern Brazil, a region with a high incidence of hantavirus pulmonary syndrome. The 14 small mammal species captured were composed of 10 rodents and four marsupials, the six most abundant species being Akodon serrensis, Oxymycterus judex, Akodon montensis, Akodon paranaensis, Oligoryzomys nigripes, and Thaptomys nigrita. These species displayed a similar pattern with increasing population sizes in fall/winter caused by recruitment and both, increase in reproductive activity and higher hantavirus prevalence in spring/summer.

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A 3-year ecological study of small mammals was carried out in an endemic area for hantavirus pulmonary syndrome in the state of Santa Catarina in Southern Brazil. A total of 994 rodents of 14 different species corresponding to the subfamilies of Sigmodontinae, Murinae, Eumysopinae, and Caviinae were captured during 2004-2006. Oligoryzomys nigripes and Akodon montensis were the most abundant species and showed a clear seasonal pattern with higher population sizes during the winter.

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Paraná state presents the fourth highest number of accumulated cases of hantavirus pulmonary syndrome in Brazil. To map the risk areas for hantavirus transmission we carried out a study based on rodent trapping and determined the anti-hantavirus seroprevalence in these animals and in the inhabitants of these localities. Overall seroprevalence in rodents and humans were 2.

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We characterised hantaviruses circulating in different Akodon rodent species collected in midwestern Santa Catarina (SC), southern Brazil, where the Jabora hantavirus (JABV) strain was first identified in Akodon montensis. Genetic and phylogenetic analyses based on a partial S segment indicated that, in SC, Akodon paranaensis and A. montensis carried the same type of hantavirus.

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Chagas disease was investigated in four periurban areas of Ceará state, northeastern Brazil, through serological, parasitological and molecular methods in humans, reservoirs and vectors. A cross-sectional survey revealed a seroprevalence rate of 1.2% (13/1076 residents, six also proving positive through PCR).

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Over 1,100 cases of hantavirus pulmonary syndrome (HPS) have occurred in Brazil since 1993, but little is known about Brazilian hantaviruses, and many of their rodent hosts remain unknown. The Araucaria hantavirus (ARAUV) was described recently from HPS patients from Paraná, in southern Brazil, but its host could not be identified. In this study, rodents were captured from regions with high HPS prevalence to address this issue.

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South American histricognath rodents Thrichomys apereoides laurentius and Thrichomys pachyurus are natural hosts of Trypanosoma cruzi, agent of Chagas disease. We established breeding colonies of these species to serve as experimental models in various parasitological studies. Both species of Thrichomys have all the requirements necessary to become excellent laboratory models: they can be easily maintained in the standard laboratory conditions and breed throughout the year and they do not have any special dietary demands and can be fed by standard food pellets designed for laboratory mice.

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