Search bioRxiv⌕ Search

Biology subjects

Teixeira, D. S.

Publications and source records attributed to Teixeira, D. S..

3 recordsLinked to original sources

Fast surveillance response and genome sequencing reveals the circulation of a new Yellow Fever Virus sublineage in 2021, in Minas Gerais, Brazil

Yellow fever virus (YFV) exhibits a sylvatic cycle of transmission involving wild mosquitoes and non-human primates (NHP). In Brazil, YFV is endemic in the Amazon region, from where waves of epidemic expansion towards other Brazilian states eventually occur. During such waves, the virus usually follows the route from North to the Central-West and Southeast Brazilian regions. Amidst these journeys, outbreaks of Yellow Fever (YF) in NHPs, with spillovers to humans have been observed. In the present work, we describe a surveillance effort encompassing the technology of smartphone applications and the coordinated action of several research institutions and health services that succeeded in the first confirmation of YFV in NHPs in the state of Minas Gerais (MG), Southeast region, in 2021, followed by genome sequencing in an interval of only ten days. Samples from two NHPs (one of the species Alouatta caraya in the municipality of Icarai de Minas and the other of the species Callithrix penicillata in the municipality of Ubai) were collected and the presence of YFV was confirmed by RT-qPCR. We generated three near-complete by Nanopore sequencer MinION. Phylogenetic analysis revealed that all viral genomes recovered are equal and related to lineage South America 1, clustering with a genome detected in the Amazon region (Para state) in 2017. These findings reveal the occurrence of a new wave of viral expansion in MG, six years after the beginning of the major outbreak in the state, between 2015-2018. No human cases were reported to date, showing the importance of coordinated work between local surveillance based on available technologies and support laboratories to ensure a quick response and implementation of contingency measures towards avoiding the occurrence of YF cases in humans.

molecular biology↗

No evidence of SARS-CoV-2 infection in Neotropical Primates sampled during COVID-19 pandemic in Minas Gerais and Rio Grande do Sul, Brazil.

In 2019, a new coronavirus disease (COVID-19) was detected in China. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was capable to infect domestic and captive mammals like cats, tigers and minks. Due to genetic similarities, concern about the infection of Non-Human Primates (NHPs) and the establishment of a sylvatic cycle has grown in the Americas. In this study, neotropical primates (NP) were sampled in different areas from Brazil to investigate whether they were infected by SARS-CoV-2. A total of 89 samples from 51 NP of four species were examined. No positive samples were detected via RT-qPCR, regardless of the NHP species, tissue or habitat tested. This work provides the first report on the lack of evidence of circulation of SARS-CoV-2 in NP. The expand of wild animals sampling is necessary to understand their role in the epidemiology of SARS-CoV-2.

microbiology↗

Howler monkeys are the reservoir of malaria parasites causing zoonotic infections in the Atlantic forest of Rio de Janeiro

BackgroundAlthough malaria transmission was eradicated from southeast Brazil, a significant increase in the number of Plasmodium vivax-like autochthonous human cases has been reported in remote areas of the Atlantic Forest in the last decades in Rio de Janeiro (RJ) state, including an outbreak in 2015-2016. The singular clinical and epidemiological aspects of several human cases combined with molecular and genetic data revealed that they were due to the non-human primate (NHP) parasite P. simium. The full understanding of the epidemiology of the autochthonous malaria in southeastern Brazil depends, however, upon the knowledge on the circulation of NHP Plasmodium in the foci and the determination of its reservoirs.\n\nMethodologyA large sampling effort was carried out in the Atlantic forest of RJ and its bordering states (Minas Gerais, Sao Paulo, Espirito Santo) for capture and examination of free-living NHPs. Blood and/or viscera were analyzed for Plasmodia infections through molecular and microscopic techniques.\n\nPrincipal findingsIn total, 146 NHPs of six species, from 30 counties in four states were tested. Howler monkeys (A. guariba clamitans) were the only NHP species found infected. In RJ, 26% of howlers were positive, among them 17% were found to be infected with P. simium. Importantly, specific single nucleotide polymorphisms were detected in all P. simium infected howlers regardless geographical origin of malaria foci. Interestingly, 71% of P. simium infected NHP were from the coastal slope of a mountain chain (Serra do Mar), where most human cases have been occurring. P. brasilianum/malariae was detected for the first time in 14% free-living howlers in RJ as well as in 25% of those from the Espirito Santo state. Moreover, malarial pigment was detected in spleen fragments of 50% of a subsample composed of howler monkeys found dead in both RJ and ES. All NHPs were negative for P. falciparum.\n\nConclusions/SignificanceOur data indicate the howler monkeys as the main reservoir of the Atlantic forest human malaria in RJ and other sites in Southeast Brazil and reinforce its zoonotic nature.\n\nAuthor summaryThe present work consists of an unprecedented capture effort and large-scale field survey of plasmodial species in Non-human primates (NHPs) in RJ, a state recording a three-decade history of autochthonous human cases of benign tertian malaria pending epidemiological clarification of their origin. For the first time, we describe infection rates by Plasmodium sp.in free-living NHP, match the spatial distribution of P. simium in NHP with that of local human cases of benign tertian malaria due to this parasite, disclose howler monkeys as the only confirmed reservoir of this zoonotic malaria in the state and showed that specific single nucleotide polymorphisms were present in all P. simium infected howlers, regardless of the geographical origin of malaria foci. It is also the first time that P. brasilianum/malariae is recorded in free-living NHPs from Rio de Janeiro and the widespread distribution of this quartan-malaria parasite of zoonotic potential in the state is illustrated. Together, these findings increase the understanding about the simian malaria parasites in Atlantic Forests, as well as on the zoonotic character of autochthonous human malaria in Rio de Janeiro, providing subsidies for shaping surveillance and control.

ecology↗