Fever / Flu / PUO

ID-Fever / PUO Multiplex Panel

Simultaneous detection of viruses, parasites and bacteria causing acute febrile illness and pyrexia of unknown origin from one sample.

Method
Real-time multiplex PCR
Turnaround
≈ 5 hours (ID Labs stated specification)
Specimen
Whole Blood (EDTA), Serum, Nasopharyngeal Swab
Sample volume
Data to be updated

Why This Test Matters

Pyrexia of unknown origin remains a clinical challenge despite better understanding of causative diseases and wider access to tests — about 51% of PUO cases remain undiagnosed in the literature cited by ID Labs. Fever accounts for a large share of consultations and is one of the most common reasons for hospital admission, with real mortality and loss of life expectancy when diagnosis is delayed.

Clinical Background

In tropical practice, malaria, dengue (all four serotypes), chikungunya, enteric (typhoid) fever, leptospirosis, scrub typhus and influenza-like illness present with overlapping, non-specific features. Multiplex PCR differentiates the causes of febrile illness — including malaria, radiologically confirmed pneumonia and typhoid fever — from a single sample.

The Diagnostic Challenge

Culture is significant only for bacterial infections and takes ~72 hours; serology takes 5–7 days and contributes little to acute management. Symptom-based empirical diagnosis alone cannot separate treatable causes that demand completely different therapies.

Current Diagnostic Methods

Malaria smear and antigen tests, dengue NS1/antibody serology, blood culture for enteric fever, and single-plex PCRs each answer one question at a time, consume separate samples and extend the diagnostic odyssey.

How the ID Labs Test Helps

ID-Fever Multiplex assays simultaneously detect viruses, parasites and bacteria in one sample, enabling faster and more appropriate treatment decisions when they matter most — including serotype-level dengue differentiation and species-level Plasmodium identification by distinct amplification signatures.

How the Test Works

  1. 01Sample collection (blood / appropriate specimen)
  2. 02Nucleic acid extraction
  3. 03Multiplex real-time amplification
  4. 04Target-specific detection incl. Tm-based discrimination
  5. 05Internal control check
  6. 06Report

Test Methodology

MethodologyReal-time multiplex PCR
TechnologyReal-time multiplex PCR
InstrumentData to be updated
DetectionFluorescence amplification with amplicon melt/Tm discrimination

Specimen Information

Whole Blood (EDTA)

Collection
Venepuncture into EDTA tube using aseptic technique.
Minimum volume
2 mL
Recommended
3–5 mL
Transport
2–8 °C, do not freeze
Storage
2–8 °C
Stability
Data to be updated
Rejection criteria
Clotted, haemolysed or unlabelled samples; wrong anticoagulant.

Serum

Collection
Venepuncture into plain/serum-separator tube; allow clotting and centrifuge.
Minimum volume
0.5 mL
Recommended
1–2 mL
Transport
2–8 °C
Storage
2–8 °C short term; −20 °C for longer storage
Stability
Data to be updated
Rejection criteria
Gross haemolysis, lipaemia, insufficient volume.

Nasopharyngeal Swab

Collection
Flocked swab inserted through the nostril to the posterior nasopharynx; placed in viral transport medium.
Minimum volume
1 swab in VTM
Recommended
1 swab in 2–3 mL VTM
Transport
2–8 °C
Storage
2–8 °C
Stability
Data to be updated
Rejection criteria
Dry swab without transport medium; broken swab shaft.

Specimen Container

EDTA Tube (K2/K3 EDTA)

Evacuated blood tube · Cap: Lavender / Purple

Additive: K2/K3 EDTA (anticoagulant)

Volume: 3 mL

Invert gently 8–10 times after collection. Do not freeze.

Viral Transport Medium (VTM) Tube

Swab transport tube · Cap: Varies

Additive: Viral transport medium

Volume: 2–3 mL VTM

Break swab shaft into medium; cap tightly.

Targets / Analytes / Organisms

Viruses

Dengue virus (serotypes 1–4)Chikungunya virusInfluenza A virusInfluenza B virusAll four dengue serotypes differentiated by unique amplicon Tm (ID Labs stated specification)

Parasites

Plasmodium falciparumPlasmodium vivaxPlasmodium malariaePlasmodium ovaleAll four Plasmodium species differentiated in a single reaction

Bacteria

Salmonella enterica serovar TyphiLeptospira spp.Orientia tsutsugamushiAdditional regional fever targets — data to be updated

Technical Performance

CharacteristicValueSource
ScopeViruses, parasites and bacteria in one sample, providing a comprehensive patient profileID Labs Specification
Turnaround timeApproximately 5 hoursID Labs Specification
Analytical / clinical performancePerformance characteristics: please contact ID Labs — data to be updated.ID Labs Validated Performance

Clinical Utilization

Use early in the workup of undifferentiated fever, particularly in endemic seasons and returning travellers. Early aetiological diagnosis supports treatment, surveillance, outbreak control and rational antimicrobial use.

Advantages

  • One sample, many pathogens — comprehensive febrile-illness profile
  • Differentiates all four dengue serotypes and four Plasmodium species (ID Labs stated specification)
  • Fast: approximately 5 hours
  • Reduces sequential testing, time and cost

Limitations

  • Window period: very early infections may fall below the limit of detection
  • Detects only panel targets — a negative panel does not exclude other causes of PUO
  • Serology may still be required for staging or for pathogens best diagnosed serologically
  • Malaria parasite density for management decisions still requires microscopy
  • Target-specific performance — data to be updated

Conventional vs Advanced Technology

Conventional fever workup vs ID-Fever Multiplex
FeatureCultureSerologyID-Fever Multiplex
Pathogens per testBacteria onlySingle pathogenViruses + parasites + bacteria
Time≈ 72 hours5–7 days≈ 5 hours
Value in acute managementConfirmatoryLowDirectly guides therapy

Diagnostic Algorithm

  1. 01Patient with acute febrile illness / PUO
  2. 02Clinical assessment + malaria smear as indicated
  3. 03ID-Fever Multiplex PCR (≈5 h)
  4. 04Aetiology-directed therapy
  5. 05Serology/culture for confirmation where indicated
  6. 06Escalated PUO workup if unresolved

Publications & Scientific Evidence

Multiplex PCR in the differential diagnosis of fever of unknown origin and acute febrile illness

Published Scientific Evidence (various authors)

Peer-reviewed literature

ReviewCitation only

The published literature supports syndromic multiplex PCR as a tool for the differential diagnosis of undifferentiated febrile illness, particularly where multiple treatable pathogens (dengue, malaria, enteric fever, rickettsioses, leptospirosis) present with overlapping clinical features. Specific assay performance is target- and platform-dependent. Full citations for this collection are being curated.

Multiplex PCR for tropical acute febrile illness and malaria co-infections in central India

Medical Research Archives (ESMED) · 2024

Clinical StudyExternal link only

Curated peer-reviewed / authoritative reference. Open the source link for the full text.

Comparison of rapid tests and multiplex PCR for dengue, malaria and chikungunya in acute febrile illness

BMC Infectious Diseases · 2017

Comparative StudyExternal link only

Curated peer-reviewed / authoritative reference. Open the source link for the full text.

Related Tests & Technologies

Frequently Asked Questions

References

  1. Published literature on multiplex PCR in undifferentiated febrile illness (PubMed search)

Discuss this test with our scientific team

Panel configuration, specimen logistics and turnaround details on request.

Enquire now

Information on this page is educational and does not replace professional clinical judgment. Performance values are labelled by source (ID Labs Specification / ID Labs Validated Performance / Manufacturer Specification / Published Scientific Evidence). Molecular results must be correlated clinically and, where appropriate, confirmed by culture and phenotypic susceptibility testing.