Viral Antigen Panel in Stool

1. Objective


To detect specific viral antigens in stool samples using immunoassay-based panels, aiding in the diagnosis of viral gastroenteritis.

2. Principle

This panel uses enzyme immunoassay (EIA) or immunochromatographic rapid tests to detect viral proteins (antigens) in fecal specimens. Monoclonal or polyclonal antibodies specific to common gastrointestinal viruses are used to capture and indicate the presence of viral antigens. Positive reactions result in a colorimetric or fluorescent signal.

3. Common Viruses Detected

  • Rotavirus 

  • Norovirus (GI and GII)

  • Adenovirus (types 40/41)

  • Astrovirus

  • Sapovirus (optional in extended panels)

4. Materials

  • Viral antigen test kit or multiplex panel (ELISA, immunochromatographic strip, or automated analyzer)

  • Fresh stool sample

  • Sample buffer/diluent

  • Micropipette/dropper

  • Disposable gloves, PPE

  • Timer 

  • Waste disposal container

5. Procedure

  1. Collect a fresh stool sample in a sterile container.

  2. Prepare the sample using the buffer provided in the test kit.  

  1. Apply the sample to the appropriate wells or test strips.

  2. Incubate for the specified time (varies by method).

  3. Interpret the results according to the manufacturer’s instructions.

In multiplex systems (e.g., FilmArray GI Panel or BioFire), PCR-based detection may replace antigen testing.

6. Result Interpretation

  • Positive: Detection of one or more viral antigens → acute viral gastroenteritis.

  • Negative: No viral antigens detected → rule out major viral causes.

  • Invalid: Faulty test control → repeat required.

7. Clinical Uses

  • Rapid diagnosis of viral diarrhea, especially in children, immunocompromised patients, or during outbreaks.

  • Differentiation from bacterial or parasitic causes of diarrhea.

  • Support in infection control and public health surveillance.

  • Useful in outbreak investigations (e.g., norovirus in schools or cruise ships).

8. Conclusion

The Viral Antigen Panel in Stool is a rapid, specific, and non-invasive diagnostic tool for identifying viral gastroenteritis pathogens. It is highly valuable in both clinical and public health settings for early diagnosis, treatment decisions, and containment of infectious outbreaks.

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