Cholera Test

 


1. Objective

The objective of the test was to detect the presence of Vibrio cholerae, the bacterium responsible for cholera, in stool samples or rectal swabs, aiding in diagnosis and outbreak control.

2. Principle

The test was based on isolating and identifying Vibrio cholerae using culture, microscopy, or rapid immunochromatographic test kits. Culture allowed confirmation, while rapid tests gave quicker preliminary results by detecting cholera antigen in stool.


3. Materials

Depending on the method used:

✔ For Culture:

• Fresh stool sample or rectal swab

• Transport media (Cary-Blair)

• Selective media (Thiosulfate Citrate Bile Salts Sucrose agar – TCBS)

• Enrichment broth (Alkaline Peptone Water)

• Microscope and staining reagents

• Oxidase reagent

• Biochemical test kits

✔ For Rapid Cholera Dipstick Test:

• Stool sample

• Cholera antigen rapid test cassette

• Extraction buffer

• Dropper

• Timer

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4. Procedure

🧪 A. Culture Method

1. Stool was enriched in Alkaline Peptone Water and incubated for 6–8 hours.

2. The culture was streaked onto TCBS agar and incubated at 37°C.

3. Yellow colonies were suspected V. cholerae.

4. Colonies were confirmed using oxidase test and biochemical profiling.

🧪 B. Rapid Test

1. Stool sample was mixed with buffer and applied to the test cassette.

2. The result was read within 15–20 minutes.

3. A visible test line indicated presence of V. cholerae O1/O139 antigen.

5. Result (Example)

Test Type Result Interpretation

TCBS Culture Yellow colonies Vibrio cholerae isolated

Oxidase Test Positive Confirmed Vibrio species

Rapid Test Positive line Cholera antigen detected

6. Uses

• Diagnosed cholera in suspected cases with acute watery diarrhea

• Helped in cholera outbreak detection and control

• Guided prompt rehydration and antibiotic therapy

• Essential in areas with poor sanitation or contaminated water

7. Conclusion

The cholera test was a rapid and reliable tool to confirm the presence of Vibrio cholerae, critical for timely treatment, public health interventions, and preventing spread during outbreaks.

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