Medical virology · NHS Bands 2–8

Virology interview questions and training for NHS biomedical scientists

Virtual virology lab covering BBV / respiratory / COVID surveillance, advanced LIMS, molecular techniques, PCR depth and viral immunology, with reference to UK SMIs (for example V 11, HIV screening and confirmation) and UKAS standards.

Reviewed by Desmond O., HCPC-registered Biomedical Scientist, and the PathologyLabTraining editorial team

UK SMIs
UKAS / ISO 15189
NGS & molecular
Bench simulation

Virtual virology laboratory suite

Immersive virology training: viral culture, electron microscopy, NGS sequencing, biosafety, COVID surveillance and hepatitis monitoring on a high-fidelity virtual bench.

Virtual Virology Laboratory Suite is available to premium subscribers and trial users.

LIMS

Advanced virology science LIMS

Next-generation laboratory information management for virology testing, molecular diagnostics, serology validation and cross-departmental correlation.

Advanced Virology Science LIMS is available to premium subscribers and trial users.

Molecular diagnostics

Molecular techniques

Interactive tools for molecular diagnostic techniques including PCR, sequencing and genotyping.

PCR Techniques

  • • Real-Time PCR (qPCR): Quantitative viral load; limits of detection are assay specific, and HBV DNA and HCV RNA are reported in IU/mL
  • • RT-PCR: RNA virus detection with a reverse transcription step
  • • Multiplex PCR: Multiple target detection; sensitivity for each target must be verified in the multiplex format
  • • Digital PCR (dPCR): Absolute quantification without standard curves

Sequencing Methods

  • • Sanger sequencing: Targeted viral regions
  • • Next-Generation Sequencing (NGS): Whole viral genomes; required coverage depth depends on the application
  • • Metagenomic approaches: Novel virus detection
  • • Phylogenetic analysis: Outbreak investigations

Genotyping & Resistance Testing

  • • HIV drug resistance testing
  • • HCV genotyping for treatment selection
  • • Influenza antiviral resistance screening
  • • SARS-CoV-2 variant surveillance and characterisation

Innovative Technologies

  • • CRISPR-based diagnostics: SHERLOCK/DETECTR
  • • Nanopore sequencing: Rapid field testing (real-time analysis, portable)
  • • Digital microfluidics: Point-of-care testing
  • • Machine learning: Variant calling, resistance prediction, outbreak tracking

Sample Processing & Quality

  • • Automated extraction: 96-well platforms
  • • Internal controls: PCR inhibition monitoring (an internal control Ct shift beyond the laboratory's validated limit indicates inhibition)
  • • Contamination prevention: UNG treatment, separate workstations, one-way workflow
  • • Quantification standards: WHO International Standards (metrological traceability)
Amplification

PCR guide

Comprehensive guide to PCR techniques: real-time PCR, RT-PCR and digital PCR methods used in NHS virology.

Real-Time PCR

  • • Detects amplification as it occurs using fluorescence
  • • Higher sensitivity and specificity than conventional PCR
  • • Allows for quantification of viral load
  • • Common for HIV, HCV, and HBV viral load testing

RT-PCR

  • • Reverse transcription followed by PCR
  • • Used for RNA viruses (HIV, SARS-CoV-2, influenza)
  • • Converts RNA to cDNA before amplification
  • • Critical for respiratory virus diagnostics

Multiplex PCR

  • • Detects multiple pathogens in a single reaction
  • • Useful for respiratory and gastrointestinal panels
  • • Saves time and specimen material
  • • Requires careful primer design to avoid interference

Digital PCR

  • • Partitions sample into thousands of individual reactions
  • • Absolute quantification without standard curve
  • • Higher precision for low viral loads
  • • Used for residual viraemia detection in HIV and HBV
Serology

Viral immunology guide

Reference guide for viral immunology with diagnostic pathways and laboratory findings.

Viral Serology

  • • Detection of antibodies against viral antigens
  • • IgM indicates recent or acute infection
  • • IgG indicates past infection or immunity
  • • Commonly used for HIV, hepatitis, EBV, CMV, and flaviviruses

Immunoassay Types

  • • ELISA: high-throughput screening
  • • Western blot: confirmatory testing
  • • Immunofluorescence: direct viral antigen detection
  • • Rapid diagnostic tests: point-of-care testing

Interpretation Challenges

  • • Cross-reactivity between related viruses
  • • Window period before antibody development
  • • Persistence of IgM in some viral infections
  • • Impact of immunosuppression on antibody production

Cellular Immunity Testing

  • • IGRA for latent TB and viral CMV assessment
  • • ELISpot for T-cell responses
  • • Flow cytometry for lymphocyte subsets
  • • Important for latent viral infection assessment

Advanced Serological Methods

  • • Avidity testing for acute vs past infection differentiation
  • • Neutralising antibody assays for functional immunity
  • • Multiplex bead-based immunoassays for comprehensive profiles
  • • Chemiluminescent immunoassays (CLIA) for high sensitivity

Quality Assurance in Viral Serology

  • • Signal-to-cut-off (S/CO) ratio interpretation: reactive, equivocal and non-reactive thresholds are assay specific and are set by the manufacturer's instructions for use
  • • Equivocal results (grey zone): repeat testing or alternative method confirmation required
  • • Index value calculations: (Sample OD / Cutoff OD) with proper controls validation
  • • External quality assessment (EQA) participation
  • • Method comparison studies for assay validation
Surveillance data

Virology data visualisation

Interactive charts and graphs showcasing key virological parameters and diagnostic patterns.

Simulated. Every figure on this page is generated for teaching: the prevalence split, the resistance trends and the assay performance table. None of it is surveillance data and none of it should be quoted as a national figure. Any confidence, accuracy or performance figure shown below is part of the simulation, not a measurement from a laboratory or a validated model.

Viral Load Distribution

Illustrative distribution of viral load categories across different viruses (teaching values). HBV DNA and HCV RNA are reported in IU/mL against WHO International Standards; categories here are not clinical thresholds, which are assay and guideline specific.

Foundations

Virology quick guide

Essential knowledge areas for virology, from foundational concepts to specialised techniques.

Clinical Virology for Senior BMS

Clinical virology is a specialised branch of microbiology focusing on the detection, diagnosis, and monitoring of viral infections. Senior Biomedical Scientists play a crucial role in leading complex viral diagnostic testing and implementing advanced molecular techniques. Current UK practice incorporates UKHSA's ongoing metagenomic surveillance (mSCAPE) and enhanced respiratory virus genomic surveillance programs supporting national pathogen surveillance.

Core Responsibilities

  • Development and validation of viral diagnostic assays
  • Interpretation of complex molecular testing results
  • Quality assurance and method verification
  • Outbreak investigation support
  • Surveillance program management

Advanced Testing Methods

  • Next-generation sequencing (NGS)
  • Digital PCR and multiplex PCR
  • Viral load quantification
  • Antiviral resistance testing
  • Whole genome viral sequencing

Sources and guidance

This hub's content aligns with the UK's professional and regulatory references for the specialty: