Publications by authors named "Andre F A Santos"

Background: Bat-borne hantaviruses have been identified worldwide but little is known about neotropical bats in the megadiverse biomes of the American continent. Although serological evidence has hinted at hantavirus circulation in Brazil, the scarce number of genomic detection represents a gap to understand viral diversity, prevalence, and ecology of bat-borne hantaviruses.

Objective: We aim to investigate and evaluate the presence and prevalence of bat-borne hantavirus in the Brazilian Atlantic Forest.

View Article and Find Full Text PDF

Toxoplasmosis is an important zoonotic disease caused by the parasite and is especially fatal for neotropical primates. In Brazil, the Ministry of Health is responsible for national epizootic surveillance, but some diseases are still neglected. Here, we present an integrated investigation of an outbreak that occurred during the first year of the COVID-19 pandemic among eleven neotropical primates housed at a primatology center in Brazil.

View Article and Find Full Text PDF

Gut microbiome disruptions may lead to adverse effects on wildlife fitness and viability, thus maintaining host microbiota biodiversity needs to become an integral part of wildlife conservation. The highly-endangered callitrichid golden lion tamarin (GLT-Leontopithecus rosalia) is a rare conservation success, but allochthonous callitrichid marmosets (Callithrix) serve as principle ecological GLT threats. However, incorporation of microbiome approaches to GLT conservation is impeded by limited gut microbiome studies of Brazilian primates.

View Article and Find Full Text PDF

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 introduced, knowledge about viral diversity remains poorly studied. Therefore, using metagenomics based on virus enrichment, we explored the viral microbiota present in the feces of introduced common marmosets (Callithrix sp.

View Article and Find Full Text PDF

The development of high-throughput sequencing (HTS) technologies and metagenomics protocols deeply impacted the discovery of viral diversity. Moreover, the characterization of novel viruses in the Neotropical primates (NP) is central for the comprehension of viral evolution dynamics in those hosts, due to their evolutionary proximity to Old World primates, including humans. In the present work, novel anelloviruses were detected and characterized through HTS protocols in the NP , the common black-tufted marmoset.

View Article and Find Full Text PDF
Article Synopsis
  • A 10-year-old black howler monkey exhibited a 36-day period of symptoms including fever, lethargy, loss of appetite, slow digestion, and weight loss.
  • Treatment involved the use of trimethoprim-sulfamethoxazole in combination with streptomycin.
  • Diagnosis was confirmed through the isolation of Toxoplasma gondii and PCR testing, with additional support from indirect fluorescent antibody tests showing increased antibody levels.
View Article and Find Full Text PDF

Background: During routine Coronavirus disease 2019 (COVID-19) diagnosis, an unusually high viral load was detected by reverse transcription real-time polymerase chain reaction (RT-qPCR) in a nasopharyngeal swab sample collected from a patient with respiratory and neurological symptoms who rapidly succumbed to the disease. Therefore we sought to characterise the infection.

Objectives: We aimed to determine and characterise the etiological agent responsible for the poor outcome.

View Article and Find Full Text PDF
Article Synopsis
  • In a study from Rio de Janeiro, researchers sequenced 244 genomes to track the introduction and surge of VOC Gamma, linked to a third local COVID-19 wave between late 2020 and mid-2021.
  • Findings show VOC Gamma circulated in Rio since early 2021, reaching over 70% frequency in just 7 weeks, and was linked to higher viral loads, contributing to its increased transmissibility compared to other variants.
View Article and Find Full Text PDF

Papillomaviruses (PVs) are non-enveloped icosahedral viruses with a circular double-stranded DNA genome of ∼8,000 base pairs (bp). More than 200 different PV types have been identified to date in humans, which are distributed in five genera, with several strains associated with cancer development. Although widely distributed in vertebrates, Neotropical Primates (NP) PV infection was described for the first time only in 2016.

View Article and Find Full Text PDF

Hypersusceptibility (HS) to inhibition by different antiretroviral drugs (ARVs) among diverse HIV-infected individuals may be a misnomer because clinical response to treatment is evaluated in relation to subtype B infections while drug susceptibility of the infecting virus, regardless of subtype, is compared to a subtype B HIV-1 laboratory strain (NL4-3 or IIIB). Mounting evidence suggests that HS to different ARVs may result in better treatment outcome just as drug resistance leads to treatment failure. We have identified key amino acid polymorphisms in the protease coding region of a non-B HIV-1 subtype linked to protease inhibitor HS, namely, 17E and 64M in CRF02_AG.

View Article and Find Full Text PDF

The human immunodeficiency virus type 1 (HIV-1) protease mutation D30N is exclusively selected by the protease inhibitor (PI) nelfinavir and confers resistance to this drug. We demonstrate that D30N increases the susceptibility to saquinavir (SQV) and amprenavir in HIV-1 subtype B isolates and that the N88D mutation in a D30N background neutralizes this effect. D30N also suppresses indinavir (IDV) resistance caused by the M46I mutation.

View Article and Find Full Text PDF

Background: Although extensive HIV drug resistance information is available for the first 400 amino acids of its reverse transcriptase, the impact of antiretroviral treatment in C-terminal domains of Pol (thumb, connection and RNase H) is poorly understood.

Methods And Findings: We wanted to characterize conserved regions in RT C-terminal domains among HIV-1 group M subtypes and CRF. Additionally, we wished to identify NRTI-related mutations in HIV-1 RT C-terminal domains.

View Article and Find Full Text PDF

Background: Subtype C is the most prevalent HIV-1 subtype in the world, mainly in countries with the highest HIV prevalence. However, few studies have evaluated the impact of antiretroviral therapy on this subtype. In southern Brazil, the first developing country to offer free and universal treatment, subtypes B and C co-circulate with equal prevalence, allowing for an extensive evaluation of this issue.

View Article and Find Full Text PDF

Objectives: To describe the molecular and epidemiological profile of HIV-1 in patients followed at the University Hospital of Rio Grande, Brazil.

Design And Methods: A cross-sectional study was conducted from September to December 2002. Plasma viral RNA of 85 patients was extracted and protease and reverse transcriptase genes were polymerase chain reaction-amplified and sequenced.

View Article and Find Full Text PDF