Research Projects

Genomic surveillance and evolution of zoonotic viruses

Surveillance of viral pathogens using molecular methodologies is the gold standard approach for viral monitoring of reservoir and vector natural populations. However, the most used methodology, polymerase chain reaction (PCR), provides limited information about the viral lineages and spread dynamics through time, two key pieces of information needed for the implementation of effective virus control measures. Nowadays, the reduced cost of genome-wide sequencing allows a more in depth virus surveillance throught viral whole genome sequencing. In this project we aim to provide sustained whole genome monitoring of zoonotic viruses in Brazil to track epidemiological changes associated to viral lineages carrying a distinct mutational profile and understand viral lineages replacement and impact on vector competence and pathogenicity to reservoirs, vectors and humans.

Funding:
AvH - Alexander von Humboldt Foundation
FIOCRUZ - Oswaldo Cruz Foundation

 

 

Ein Mann mit Mundschutz und grünen Handschuhen kontrolliert eine Moskitofalle: Hierzu prüft er eine schwarze Tüte, die in einem Eimer steckt.
Inspecting mosquito trap for specimen collection.   ©BNITM | Rafael Maciel-de-Freitas

 

 

Colorful close up of viruses
Dengue immunofluorescence   ©BNITM | Rafael Maciel-de-Freitas

Synergistic ecological determinants of mosquito-borne virus emergence and transmission

Mosquito-borne viruses emergence and sustained transmission rely on specific biotic and abiotic ecological features that affect both hosts, virus and vectors. Several ecological determinants are known to modulate arbovirus emergence and transmission as climate conditions, abundant vector populations, vector competence, virus genotype and vector microbiome. Although there is extensive knowledge about the individual impact of these above mentioned ecological determinants, there is scant knowledge about their synergistic effect on mosquito-borne dynamics. In this project, we use preferentially the system (Aedes-Wolbachia-arbovirus-microbiome) to characterize the ecological determinants that drive mosquito-borne viruses dynamics in Brazil.

Funding:
FAPERJ - Fundação de Amparo à Pesquisa no Rio de Janeiro
CNPq - Conselho Nacional de Pesquisa e Desenvolvimento Tecnológico

Sammeln von Aedes-Eiern mit Ovitraps: grobe Holzbretter, auf denen vereinzelt sehr kleine Aedes Eier zu sehen sind.
Aedes eggs being collected with ovitraps   ©BNITM | Rafael Maciel-de-Freitas
Ein Plaque Assay: zu sehen sind mehrere Wells, die mittels eines Plaque Assays angefärbt wurden und unterschiedlich stark blau eingefärbt sind. Rechts sieht man, wie eine Person das Plaque Assay auszählt, hierzu wird mit einem Stift ein Plaque markiert.
Plaque assay dilution series for estimating viral titer.   ©BNITM | Rafael Maciel-de-Freitas
Vier Pipettenspitzen mit einer hellblauen Flüssigkeit am offenen Ende liegen Mücken, von  denen Speichel gesammelt wird.
Aedes aegypti salivation to determine arbovirus presence in mosquito salivary glands.   ©BNITM | Rafael Maciel-de-Freitas

Entomological surveillance and innovative vector control strategies

Traditional surveillance and vector control approaches have limited efficacy to prevent arbovirus outbreaks. We explore the Near-Infrared Spectroscopy (NIRS) as a rapid, non-destructive and low-cost method to determine the infection status in mosquito vectors with a main goal to improve the surveillance of mosquito-borne viruses. Furthermore, we evaluate the effectiveness of releasing mosquitoes carrying self-spreading, virus-blocking strains of the endosymbiont Wolbachia bacteria on mitigating dengue, Zika and chikungunya transmission in endemic settings. Studies based on NIRS and Wolbachia are undertaken on both laboratory, semi-field and field conditions.

Funding:
FAPERJ - Fundação de Amparo à Pesquisa no Rio de Janeiro
DFG - Deutsch Forschungsgemeinschaft

6 Bilder, die unterschiedlich Fang- und Sammelmethoden von Stechmücken
Examples of trapping and collection methods of mosquitoes   ©BNITM | Rafael Maciel-de-Freitas
Screeshot einer Karte mit entomologischen, epidemiologischen und meteorologischen Felddaten
Dashboard with entomological, epidemiological and meteorological field data to support decision making   ©BNITM | Rafael Maciel-de-Freitas

Lab Group Freitas-Wallau

  • Logo DFG
  • Logo_Alexander_von_Humboldt_Stiftung
  • Logo of FACEPE
  • Logo of FAPERJ
  • Logo of Fundacao Oswaldo Cruz