Genome Sequencing in Infectious Diseases: NGS, Oxford Nanopore and WGS

Next-Generation Sequencing (NGS) is a modern DNA sequencing technology that sequences entire genomes quickly and affordably. Unlike traditional methods that sequence short fragments one at a time, NGS processes millions of DNA strands simultaneously, providing detailed genetic insight at unprecedented speed and scale. For identification of infection, ID Labs performs NGS through Oxford Nanopore sequencing technology.

How Oxford Nanopore sequencing works 1. **Sample preparation** — DNA or RNA is extracted and prepared with the necessary adapters. 2. **Nanopore device** — the sample is introduced to a device containing nanopores embedded in a synthetic membrane. 3. **Sequencing** — as DNA or RNA strands pass through the nanopores, they disrupt an electric current; each nucleotide causes a unique disruption. 4. **Data analysis** — the disruptions are measured and analysed in real time to determine the sequence.

Advantages include long reads, real-time data generation and portability. Applications include real-time pathogen detection, field-based studies and comprehensive genomic research.

Whole Genome Sequencing WGS determines the complete DNA sequence of an organism's genome at a single time. The process: sample collection and DNA extraction → DNA fragmentation → library preparation with adapters → sequencing → assembly of fragments into a continuous genome using bioinformatics tools.

WGS provides a comprehensive view that detects a wide range of genetic variations with precision. In infectious diseases it supports resistance characterisation, strain typing and outbreak investigation — it is powerful, but it is not required for every routine infection.