Next-generation sequencing (NGS)/Whole genome sequencing (WGS) is increasingly used in clinical microbiology. Which of the following is the best application for WGS in routine outbreak investigation?
- A Routine screening of ward patients for any bacterial colonization
- B First-line rapid diagnosis of bacteraemia replacing blood cultures
- C Typing of bacterial isolates to determine clonal relatedness and transmission chains with single nucleotide polymorphism (SNP) analysis ✓
- D Measuring bacterial burden in blood (similar to viral load)
Correct answer: C. Typing of bacterial isolates to determine clonal relatedness and transmission chains with single nucleotide polymorphism (SNP) analysis
Explanation
WGS-based outbreak investigation identifies clonal transmission chains by comparing whole genome SNP differences between isolates; isolates from the same source typically have <10–20 SNPs difference. This is more discriminatory than traditional typing methods (PFGE, MLST). WGS can also simultaneously provide AMR gene profiles and virulence determinants. WGS is not a rapid diagnostic for bacteraemia (blood culture remains standard). Metagenomic NGS (mNGS) is used for culture-independent diagnosis of unusual organisms in CSF/BAL.
Reference: Ananthanarayan & Paniker's Textbook of Microbiology, 11th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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