Widal test
Quick answer: The Widal test checks your blood for antibodies against Salmonella typhi and paratyphi, the bacteria that cause typhoid fever. Doctors may order it when you have had fever for about a week or more and typhoid is suspected.
- SampleBlood
- TakesAbout 5 minutes
- Before the testNo special preparation is usually needed.
How the test is done
- 1A nurse notes how long you have had fever
- 2A vein in your arm is cleaned
- 3A needle draws a tube of blood
- 4The lab tests your serum against typhoid O and H antigens at several dilutions
What your results can mean
Reading your report
It can be positive from past infection or vaccination and negative early in illness, so a blood culture is more reliable; discuss it with your doctor.
If the result is outside the usual range
A high or rising titre can suggest typhoid or paratyphoid fever. Raised titres can also follow past infection, vaccination or other fevers, so a single result is often unreliable.
Who usually has this test
People with fever lasting about a week or more, headache, belly pain or poor appetite, when typhoid is suspected.
Risks and aftercare
No special aftercare; take any antibiotics exactly as prescribed.
Names and options
Also called: Widal, typhoid test, Widal tube test
Options
- Slide test
- Tube test
Listed by the hospital as
- WIDAL TEST
- WIDAL, SERUM (TUBE TEST)
Questions about this test
Why is a blood culture preferred over Widal?
A blood culture can grow the typhoid bacteria and show which antibiotics will work. Widal results often mislead in areas where typhoid is common.
Why might a second Widal test be done?
A four-fold rise in titre between two samples taken about a week apart is stronger evidence of typhoid than a single high result.
Can the typhoid vaccine affect the Widal test?
Yes. Some vaccines can raise Widal titres for months, so tell your doctor if you have been vaccinated.
Related tests
Tamara Hospital & IVF Centre, Rajajinagar
34/3, 10th Cross Road, opp. Vardhaka Sardar Patel School, 1st N Block, 2nd Stage, Rajajinagar, Bengaluru 560010
The hospital is open 24 hours. Call before you come to check the timing for your scan or sample collection.
Get directions ↗IVF Pulse fertility care at Tamara Hospital →
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This page explains each test in general terms so you know what to expect. It is not medical advice: your doctor decides which tests you need and what your results mean. Reference ranges differ between laboratories. Updated 4 November 2026.