What is the core difference between FICT, ELISA, PCR, and LFIA?

They detect different targets and answer different questions. LFIA and FICT are lateral-flow immunoassays that detect proteins such as antigens, antibodies, hormones, and biomarkers. ELISA also detects proteins but is a laboratory plate-based assay. PCR detects pathogen nucleic acid, DNA or RNA.

Which method is fastest for in-clinic veterinary testing?

LFIA and FICT are the fastest practical options. LFIA gives a visual result in minutes. FICT gives a quantitative instrument-read result, with Migibio analyzers reporting 3–11 minutes for many tests as manufacturer-reported.

When should I choose FICT instead of LFIA?

Choose FICT when the clinical question needs a number — for example progesterone around breeding, cPL/fPL in suspected pancreatitis, NT-proBNP for cardiac screening, or CRP/SAA for inflammation monitoring. Choose LFIA when a yes/no screening answer is sufficient.

When should I choose PCR or ELISA?

Choose PCR when molecular confirmation is needed or antigen/antibody results are inconclusive, such as early or low-level shedding. Choose ELISA for batch quantitative testing in a laboratory with higher sample volumes.

Do these methods replace one another?

No. They are complementary. A common workflow is to screen at point of care with FICT or LFIA, confirm or investigate with PCR, and use ELISA for high-volume laboratory testing.

FICT vs ELISA vs PCR vs LFIA: Choosing a Diagnostic Method

TL;DR: FICT, ELISA, PCR, and LFIA are not interchangeable. LFIA and FICT detect proteins using lateral-flow immunoassay; the difference is mainly qualitative visual readout versus quantitative instrument readout. ELISA also detects proteins, but in a laboratory plate format. PCR detects nucleic acid, not protein. For veterinary point-of-care work, FICT is the quantitative rapid-test option, LFIA is the simple screening option, while ELISA and PCR usually belong in the laboratory.

The Four Methods at a Glance

LFIA — Lateral Flow Immunoassay (conventional colloidal gold)

A specimen migrates along a membrane, and the result is usually read visually as a line. LFIA is fast, low-cost, and useful for qualitative or semi-quantitative screening.

Detects: proteins — antigens, antibodies, or biomarkers.
Result: typically qualitative yes/no, sometimes semi-quantitative.
Readout: visual line, with optional reader on some systems.
Where: point of care, field use, screening.

FICT — Fluorescence Immunochromatographic Technology

FICT is a lateral-flow immunoassay that replaces visual colloidal-gold signal with fluorescent labels and an optical reader. Because fluorescence intensity is proportional to analyte concentration, the result is quantitative.

Detects: proteins — antigens, antibodies, hormones, and biomarkers.
Result: quantitative concentration.
Readout: FIA680/FIA880 analyzer; many Migibio tests report in 3–11 minutes.
Where: point of care, quantitative monitoring, cage-side trend tracking.

See Core Technology and What is Fluorescence Immunochromatography (FICA)?.

ELISA — Enzyme-Linked Immunosorbent Assay

ELISA is a laboratory immunoassay that uses enzyme-linked detection and a standard curve. It is quantitative and well suited to batch processing.

Detects: proteins — antigens, antibodies, and biomarkers.
Result: quantitative with a standard curve.
Readout: plate reader.
Where: laboratory, batch testing, research or surveillance.

PCR — Polymerase Chain Reaction

PCR amplifies and detects pathogen genetic material. It answers a different question from immunoassays: whether pathogen nucleic acid is present.

Detects: nucleic acid — pathogen DNA or RNA.
Result: qualitative positive/negative or quantitative when assay design supports it.
Readout: thermal cycler and molecular workflow.
Where: laboratory, confirmatory testing, early or low-level infection investigation.

Head-to-Head Comparison

Criterion	LFIA (colloidal gold)	FICT	ELISA	PCR
Detection target	Protein (antigen/antibody/biomarker)	Protein (antigen/antibody/hormone/biomarker)	Protein (antigen/antibody/biomarker)	Nucleic acid (DNA/RNA)
Result type	Qualitative or semi-quantitative	Quantitative	Quantitative	Qualitative or quantitative
Time to result	Minutes, visual	3–11 minutes on Migibio analyzers (manufacturer-reported)	Hours, laboratory	Hours, laboratory
Equipment	None or optional reader	Fluorescence reader (FIA680/FIA880)	Plate reader, washer	Thermal cycler, controlled workflow
Analytical sensitivity profile	Lower than fluorescent readout	Instrument-read; pg/ml-level LOD manufacturer-reported	High	Very high
Typical veterinary role	Rapid yes/no screening	Point-of-care quantitative testing and monitoring	Batch laboratory testing	Molecular confirmation

Method Notes

LFIA

Conventional colloidal-gold LFIA is simple and inexpensive, but a visual line has limited dynamic range and is operator-dependent. Use it when the clinical question is genuinely binary and the consequence of missing a subtle change is low.

FICT

FICT keeps lateral-flow simplicity but adds a reader that converts fluorescence intensity into a numerical concentration. This supports cut-off interpretation, serial trend monitoring, and objective reporting — for example with progesterone, cPL/fPL, NT-proBNP, CRP, SAA, and SDMA. For a deeper comparison, see Fluorescence Immunoassay vs Lateral Flow.

ELISA

ELISA is a laboratory workhorse for batch analysis. It requires technical staff, standard-curve validation, and longer turnaround. It is useful when many samples are processed together or when a laboratory already has the infrastructure.

PCR

PCR offers very high analytical sensitivity for nucleic acid and is used to confirm a pathogen or investigate early/low-level infection. It requires laboratory space, trained staff, and contamination controls. A positive PCR result must still be interpreted with the clinical picture because it can detect non-viable residual nucleic acid in some situations.

Decision Guide

Clinical question	Best starting method
I need a bedside yes/no screening result	LFIA
I need a rapid quantitative concentration for diagnosis or trend monitoring	FICT
I need batch quantitative results in a laboratory	ELISA
I need molecular confirmation or direct nucleic-acid detection	PCR
Antigen/antibody result is borderline or clinically inconsistent	Confirm with PCR or an alternative laboratory method

A Practical Workflow

Screen at the point of care with FICT when a number matters, or LFIA when only a positive/negative answer is required.
Confirm unusual cases with PCR when molecular evidence is needed.
Batch high-volume work with ELISA in the laboratory.
Track chronic disease with serial quantitative FICT results, because the trend is often more informative than a single value.

Browse the full quantitative menu at Reagents, or compare the readers at FIA680 and FIA880.

Conclusion

Choose the method by the biological target and the clinical question. LFIA gives a fast visual answer, FICT gives a rapid quantitative answer at the point of care, ELISA gives batch laboratory quantification, and PCR gives molecular confirmation. In many practices, the strongest workflow is to use them together rather than pick one in isolation.