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Pullan, S. T.

Publications and source records attributed to Pullan, S. T..

2 recordsLinked to original sources

Assessment of Metagenomic MinION and Illumina sequencing as an approach for the recovery of whole genome sequences of chikungunya and dengue viruses directly from clinical samples.

The recent global emergence and re-emergence of arboviruses has caused significant human disease. Common vectors, symptoms and geographical distribution make differential diagnosis both important and challenging. We performed metagenomic sequencing using both the Illumina MiSeq and the portable Oxford Nanopore MinION to study the feasibility of whole genome sequencing from clinical samples containing chikungunya or dengue virus, two of the most important arboviruses. Direct metagenomic sequencing of nucleic acid extracts from serum and plasma without viral enrichment allowed for virus and coinfection identification, subtype determination and in the majority of cases elucidated complete or near-complete genomes adequate for phylogenetic analysis. This work demonstrates that metagenomic whole genome sequencing is feasible for over 90% and 80% of chikungunya and dengue virus PCR-positive patient samples respectively. It confirms the feasibility of field metagenomic sequencing for these and likely other RNA viruses, highlighting the applicability of this approach to front-line public health.

microbiology

Multiplex PCR method for MinION and Illumina sequencing of Zika and other virus genomes directly from clinical samples

Genome sequencing has become a powerful tool for studying emerging infectious diseases; however, genome sequencing directly from clinical samples without isolation remains challenging for viruses such as Zika, where metagenomic sequencing methods may generate insufficient numbers of viral reads. Here we present a protocol for generating coding-sequence complete genomes comprising an online primer design tool, a novel multiplex PCR enrichment protocol, optimised library preparation methods for the portable MinION sequencer (Oxford Nanopore Technologies) and the Illumina range of instruments, and a bioinformatics pipeline for generating consensus sequences. The MinION protocol does not require an internet connection for analysis, making it suitable for field applications with limited connectivity. Our method relies on multiplex PCR for targeted enrichment of viral genomes from samples containing as few as 50 genome copies per reaction. Viral consensus sequences can be achieved starting with clinical samples in 1-2 days following a simple laboratory workflow. This method has been successfully used by several groups studying Zika virus evolution and is facilitating an understanding of the spread of the virus in the Americas.

genomics