Re-emergence of Sylvatic Dengue 2 during an outbreak in Southeastern Senegal, Kedougou 2020

Abstract

Dengue outbreaks in West Africa, linked to urban cycle viruses, pose a significant public health threat. In 2020, a sylvatic Dengue 2 outbreak in Kedougou, southeastern Senegal, resulted in 59 confirmed cases, suggesting these strains may not require additional adaptation but could re-emerge into urban transmission cycles in the region.

An amplicon-based Illumina and nanopore sequencing workflow for Chikungunya virus West Africa genotype

“…Although emergence caused by the WA genotype are still localized, we are now seeing increasingly explosive outbreaks such as the one underway in Senegal (11). We designed a short amplicon scheme for WA-CHIKV WGS.…”

“…The copyright holder for this this version posted December 9, 2023. ; https://doi.org/10.1101/2023.12.07.23299611 doi: medRxiv preprint Although emergence caused by the WA genotype are still localized, we are now seeing increasingly explosive outbreaks such as the one underway in Senegal (11). We designed a short amplicon scheme for WA-CHIKV WGS.…”

“…Human sera from acute CHIKV positive cases collected in 2023 through both a CHIKV outbreak investigation in Kedougou (11) A new extraction was done by the KingFisher Flex purification system (ThermoFisher, Darmstadt, Germany) using the MagMAX Viral/Pathogen Nucleic Acid Isolation Kit (ThermoFisher) following the manufacturer's protocol. A CHIKV specific RT-qPCR (15) was performed on fresh RNA extracts before the sequencing experiments.…”

“…More recently, evidence of distribution area of this genotype has been reported with the virus detection in mosquitoes in China (9). At the time of writing, the Western African region is facing a great CHIKV outbreak with the highest numbers of cases ever reported in Senegal (10,11) and Burkina Faso (12). Recent molecular evolution analyzes have shown that the strain responsible for the epidemic in Senegal belongs to the WA genotype and highlighted the emergence of new mutations with potential impact on viral replication, antigenicity and host adaptation (11).…”